IDEAS AND LUCUBRATIONS
Worktable for the shop: The SuperTable
Heat Treating of Edged Woodworking Tools
The Cabinet Scraper A Woodworker's Friend
Hand Planing Wood The traditional way !.
Handfiling the Handsaw
The AugurBit for deep holes
Stone Carving: The Basic Technique
The Golden Mean is a wonderful set of proportions for cabinetmaker, artist, sculptor and architect. Here is a full description of its derivation, properties, and a convenient way for the woodworker to use it without extensive calculations.
MAKING THE WORKSHOP SUPER-TABLE
The SHOP TABLE has been a great subject of discussion for several centuries now. In Diderot's great 18th century "Encyclopedie.... des arts", there are great drawings of tables far beyond anything we could afford to construct now. They had cheap labor (before the Revolution!) infinite patience and some of their work-tables with many hold-downs, infinite lovely detail and fine finishing in hardwood, would now be auctioned up as "works of art".
I find many of the "Scandinavian" designs and made-up imports not very convincing. European workshops are by necessity very small, they simply do not have the space we have in a small commercial shop, a full basement or even a two-car garage space. We may feel crowded, but we really do not live in a tightly crowded world.
Let me outline my design for a SuperTable. It is the top, the working surface which is the heart of the table, any decent rough carpenter can put together legs and braces with enough wood and some time, but it is the top which is critical. That is where you do the work, anything wrong or warpable or unlevel there will be with you forever. The top must be stable, it should be fairly massive to absorb blows and to resist shudder, it is like the anvil of the blacksmith. I see no reason to use hardwood, which is expensive, tends to warp unless thoroughly dried and warp again when absorbing moisture. I have worked out a pattern which I would like to describe briefly, noting that this is a "work surface" not a show-off design.
First take a sheet of 3/4 plywood, cut a width of 32 inches as a good table width, or if you want to go heavy-duty, use two sheets which you can glue together with Titebond II using lots of drywall screws with 3/16washers around neck to spread the load. It is a good idea to pull these out later when the glue has completely set. Now this will provide the substrate for your SuperTable. I am thinking of the eight foot length as minimal for any workshop, since you use the table for the work under construction, for parts and pieces, for tools, and for your bottle of beer. Ninety-six inches in no great length when you think about it. If you want less, later you can cut is short.
Now find two planks of 2 x 12, preferable Southern Yellow Pine, which is tough, dense, and about the same strength as the lower hardwoods. A good spruce did well enough for me, fir would be nice but tends to pull up splinters under work. But it is not the wood which is important, it is the design.
Now glue these two eight foot boards onto the plywood substrate, allowing two inches for an "under-ledge" at each side which you will want for clamping if you have a supply of 6 inch C clamps. If you like bar clamps, you can put the boards nearer to the edge, which makes adding Record type woodworkers' vises easy. (Check for height of your vises first, you may want to make cutouts before gluing.). OK, now you have a 32 inch wide plywood base, you are putting on two 2 x 12's, one at each side, and you have a gap of eight inches between them at the plywood level. This gap is the heart of the SuperTable design, it gives two feet of solid supporting surface for work, with an eight inch wide lowered section which will take all the chisels, tapes, bits and anything under 11/2 inch height, while you work with all these support materials right within reach. And when you clean the table up (I do this once in a while) you find an eighth inch brush to run all the dust and scraps down to one end where you have hung a cardboard box.
I built my table a full twelve foot long, which surprises friends, but I find I use it all. I am building a piano Steinway-pattern student chair in the middle, I have all my pieces laid out on the left side, with glue and mallets over there, while on the right side I have my two sanders, the grits, the rasps for adjusting the details, and the biscuit cutter with a few jars of biscuits. Luckily I have another table at the same height which I can bring over. There is a "Law of Occupied Space" which operates in all working environments: Whatever space is available is inexorably occupied by a hand-working person, and as he or she reached the limits, a complaint about it being entirely "Too small..." always arises. So I suggest building your worktable long, since you can always cut it off with a SkilSaw.
OK, now how do you support this massive table-top. I leave that to you. Any person competent to work at such a table can figure any number of ways to support it. But I should note that the two 16 inch strips which you cut off the original plywood sheets are just right for rigidizing the top. If you made a ledge, glue and screw these onto each side into the plywood vertically, and you can stand a Ford truck on top without fear. If not a ledge-person, at least leave an inch for this plywood gusset. But if you want drawers (I did) then you have to sacrifice one side, put the panel on the far side and set your drawers on AccuRide surplus rollers now being taken out off office. equipment. These are much sturdier than the kitchen variety, can hold 150 lb. with ease.
About storage space, one way is to put the plywood left-over strip along one side (as above, under the ledge) and attach the other one down below to the finished leg structure, touching the floor. If you put your vises for planing on that low-wall side, it will prevent scraps and chips from getting under the table, where they are a bother to sweep out. You should put a deep shelf on that side above the braceing plywood, all the way through, plenty of room for the portable power tools. Now the other side will have a space under that shelf for things which you can put on the floor in boxes. There is little difference in strength from putting this one side-panel low, but you get a lot of excellent shelf space for free.
Legs and plywood braces are no problem, but again I advise gluing and screwing everything, there is simply nothing like a 25 sq. in glue joint. I like legs made solid of two 2 x 4's glued with clamps if not a 4 x 4. Speaking of glue I should mention one thing: Carpenters often think that one of the flooring tube-type construction adhesives is a strong glue. Itis an excellent filler of uneven and unclamped spaces, and has reasonable strength, but I have run comparative tests and find it has a fraction of the strength of a real wood-glue. Titebond I in a dry place, or Titebond II which is weather-"resistant" at little more cost, are strong enough to rip out segments of the glued wood on shearing, whereas the construction-adhesives usually fail in the glue. I think the strength of the table should go down through the legs, which are glued with gussets, and in places where large members meet other larger members, use several long 3/8 in. bolts WITH GLUE. (I do this always in building construction, but we can discuss that elsewhere in the construction of an affordable shop building.)
So you are going to figure out your legs and supports yourself, now let's go back to the top. I believe that one woodworkers vise is insufficient, whereas if you put two spaced along the long side of your table, they will hold a long board for planing, routing, sanding. But in many situations you want to hold the board flat on the top, and although there are many ways to do this, I believe the best is one which I have been using. I get one of those old wood-to-the-floor vise screws with its nut and wood cross-handle, drill though the plywood at the center of my table, fit the nut from the underside with its key and two screws, and fit the screw with a stout hardwood board, say 1 x 3 inches. When I want to told something down firmly, whether large or small,. I go get my screw-board and run it down into the table, set a wedge under the far side, and clamp my work firmly in place without the possibility of a scratch from metal. This board can swing around for different widths, it should reach each edge of the table, maybe one side should be a few inches shy. When not in use it hangs on the wall. With the fast thread of the old screws which are either 1/4 inch per turn (or double thread ones with 1/2 in per turn!) they are quick to get in or out.
The table top must be stable, either you leave it raw wood, or as I did, varnish it heavily BOTH top and bottom side. Once I varnished the top of a heavy table and eight years later it was so curled I had to take it apart, cut and rejoint. Now with matching coats it will last longer than its owner.
Sometimes you find a piece of work which must be held sideways, I have just been working on a marble topped coffee table with three 14" legs, I have been carving new feet. It was absolutely impossible to hold, but I have two old-fashioned wood floor-vises on the end of my table, so I put a stout board between then, hoisted the table up and clamped to the board with the feet sticking out, so the carving and finishing the legs were at waist height. Those old wood vises with the screw down the middle were always the best for wide boards, but they are useful also as holders for a variety of specialized jigs, as here.
When you are done with the construction of this table or one like it, two things remain. You must be sure it is not twisted, you can check this with a sensitive level, and plan to glue thin strips of wood under the short leg. Of course this will depend on the levelness of your wood or concrete floor, so best decide exactly where the table is to stand, and do the level checking on that spot. When you are satisfied that one end of the top surface is level to the other (if you want both feet parallel to the floor that is OK but not necessary, we are speaking about planarity of the top, not really levelness), then you may want to try something I have found good. Lever up each foot and put a gob of construction adhesive (yes, the stuff I told you not to use before) undereach foot. This will, after a week of drying, establish a firm connection between the table and the floor, and it will also prevent sideways slipping when you are working hard. This works well on a concrete floor or on wood, yet it is not so strong but that you can drive a thin/wide chisel under to break the seal later if necessary. But my point is simple: If you are 100 percent connected to your floor, your table will be firmer and much nicer to work on. When rasping, chiseling or hammering, any force lost is distracting, and only when you work on a rock-solid table will you know what a proper work-surface means.
There are many things you can later add to your table, other hold-downs, carving vises, drawers, shelves underneath, and this is (and should be) a continuing process. But the dropped center-groove of my design is something you have to consider ahead of time, and I strongly recommend it as something of such convenience that once you have used a drop-center table you will wonder how you got along before without it.
The second things I stress is stability and solidness, which come from carefully cut members, proper gusseting, and above all liberal use of glue with screws firmly set down on washers with a power driver. How you finished your table top, what actual size you decide to make it, and how well you work with it are all things in your realm, not mine. But if my design and experience helps anyone in the eternal quest for the woodworker's SuperTable, then I am more than satisfied
Every one knows how important a sharp cutting edge is in all woodworking operations, but since the days of the straight edge razor for shaving the beard, with its stone and leather strop (often used for punishing recalcitrant boys), many of us have never seen a really sharp edge. Starting from scratch, how do you get that perfect cutting edge which seems to glide through wood with a mere push of the hand?
We have always had great respect for the stone, I have several in ancient oil-darkened wooden cases, which were used for generations with the straight razor. But the razor had a great advantage since it was always hollow ground, so you could lay it flat on the stone and the back edge would serve as the angle-guide while you did the sharpening at the front. With a chisel it is quite different, I think I can get a fairly consistent angle by standing in a relaxed position at a table of given height with a familiar stone, working freehand, but I know there are small variations in my stroke since I can never get a mirror reflection on the finished bevel. Better is the sharpening jig for chisels and plane blades with its angle adjustment and rollers, but you have to set the angle for each tool and those angles will never be exactly or the same. I've given up on the rolling jigs. What about the stones? There are the little Arkansas slip stones which do cut well, and are fine for a finishing touch-up, but again you have no control over the angle other than your hand and eye. The Japanese natural stones in water are excellent cutters, for some years now there has been a fad of using them as the ultimate in sharpening, but the old problems of angle persist. For the Japanese woodworker with his elegant two-steel hard-edged chisels there is no problem, since he does all the sharpening on the flat side of the chisel, which is hollow ground in an oval pattern at the factory. He just lays the chisel flat on a wet water stone and rubs until sharp, a neat way of doing it, and the only proper way to sharpen Japanese chisels.
Oil stones or water stones, that is the question. Water is clearly better since it lubricates and easily washes off particles of metal along with broken stone crystals. Oil oxidizes and eventually gums up the stone, unless you use a light oil like kerosene and keep the stone stored in a bath, but that is messy around wood. (I have discovered that old oil soaked stones will shed their oil if soaked in a bath of water, the oil eventually detaches and floats to the surface. You go back every six months and wipe the stone off, but it can take up to five years to clean them out. Discouraging, but the five years are going to pass anyway....)
I have a clear preference which goes in an entirely different direction. I use a belt sander with several worn-out belts carefully saved for fine-sharpening blades. I won't use these for serious reshaping because they cut too slowly and generate too much heat but they do a great job removing a small amount of metal and leaving a high degree of polish. I must be sure the backup surface against which the belt runs is flat and doesn't show wear pockets, if worn it needs to be sanded out on another machine. First I grind the flat side of the blade being sure I don't bevel the edge by letting it hit the belt first. It is surprising how often wear will put a small bevel on the flat of a chisel or plane blade,which must be completely flat to cut right.
Then I proceed to the bevel. I do this by eye and feel, watching to see that I am approaching the cutting edge carefully and not canting to one side. I like to hold the blade at a slight side-angle to the belt, it might be better to do this with a home-made jig to ensure a consistant angle. About 30 degrees seems to work well for ease of cut and durability, this would be five minutes on a clock face, and drawing that angle out on paper might be a good check. The main thing here is to keep the work cool by dipping it is water frequently.I keep a finger near the edge to feel the heat building up. But always dip if in question.
While speaking of heat and losing the edge, something about heat-treatingmay be in order. For a chisel used with a mallet in hard wood, the cutting edge should be just "touchable" by a file, that is the file will bite a wee bit. If the edge is "dead hard" the file will slip over it like glass. For chisels and gouges used for hand-push, the harder the better, so long as you don't wedge which can snap the edge. I will discuss re-heat-treating chisels in another place, but here the caution is clear: If you have heated a chisel on the belt sander so that any portion of the edge turns blue, you have removed a great deal of the hardening. This does not mean that the chisel is useless, it will still take an excellent edge. But it will not be full-hard, as the file test will prove. (You can harden it yourself, we will talk about that another time.)
So now if you are following my suggestions, you have got your angles done right on the belt sander, the flat is really flat to the edge and the angle is about right.
At this point I suggest going to another process which will give you a razor edge in about thirty seconds.For this you will need a motor with a 1/2 or 5/8 inch shaft, an old one you pick up at a yardsale will be fine, l750 RPM is the most common and better than 3400 RPM which generates too much heat I feel. You can get from a hardware store or woodworking supply a motor-arbor which slips over motor shaft and adapts to a wheel with a half inch hole (arbors cost under $5). Now you will have to search a bit to find a "hard" felt wheel at least 1/2 inch wide in six inch diameter, as last resort look in the giant Thomas Register under Polishing. Don't even try this with a soft polishing wheel, which will round the edges over and lose the whole concent of the "narrow acutance edge".You will need a block of rouge compound, Tripoli may be a little too coarse and black emery is really not fine enough. There are white compounds which work fine too, the supplier can usually tell you what is best for your purpose.
Caution: Be sure you set this up to the top of the wheel rotates AWAY from you, and do the following procedures with the blade pointing upwards and on the upper half of the wheel. (This may be an unnecessary precaution, but if you catch the sharp edge on a down-turning wheel it will throw the work and probably gouge the wheel.) Now you are ready to do the final sharpening. Load the wheel by holding the rouge against it for a second, press the chisel against the wheel on the flat side first with as flat an angle as will just about reach to the cutting edge, to avoid putting a micro-bevel onto that side which you care so carefully flattened. Now go to the bevel side, again trying to match the periphery of the wheel to the bevel angle of the tool. This takes a bit of care and examining the bevel as it polishes, but it is a matter of common sense and trial. Don't give it too much angle or you will change the bevel.
This final polishing process takes just a few seconds, firm pressure with the same angle, examine it, cool if warming and you are done. How good is the edge now? I always test with a light touch on the hair of my left arm, if it is perfect it will slice off a few hairs, and I know I have the best possible edge. (Testing too often will give a strange, splotchy look to your arm when you go swimming, so best go easy with this.)
The advantages of my method of
sharpening are these.
Heat treating of ferrous metal tools is an ancient practice, it is known as far back as the early Greeks, and may be a good thousand years older. Homer who was writing around 800 B.C. knew about heating and quenching of iron, in fact he compared Odysseus jamming a spearpoint of heated wood into the Cyclops' eye as "giving a sound like that of a blacksmith quenching his iron" at the forge, remarking of the quench: "For that is the strength of iron, specifically...". In fact that last word shows that he was aware of the opposite effect of softening for the same process used with a copper-based alloy like bronze.
Iron which has a very small amount of carbon in its composition, can be hardened by heating to a given temperature and then cooling suddenly. If the carbon content is larger than a critical amount, the materials melts and pours more easily, but becomes what we call "cast iron" which does not have heat treating properties. It is strong on impact and compression, but brittle and poor in tension, so it cannot be used for edged tools, which is probably why bronze (which can be work-hardened by hammering a knife edge) continued as the basic material for tools for so long. It is hard to know when the iron in the crucible has the proper amount of carbon for hardening, but it can be estimated by trial and error. Perhaps the earliest iron was found in ferritic meteoric pieces which had burned out all the carbon in hot transit; by adding bits of wood to the mix, if carefully done, people did learn finally to produce a"20/30 point" iron suitable for tools. This must have seemed a magical process in the early days, and the process was guarded in great secrecy, which explains the slow development of an Iron Economy in antiquity.
When steel, which is just the name we give to iron which has the right carbon percentage, is heated to a bright yellow in daylight, it changes its molecular state. We now know that it loses its ability to be magnetized, the molecules are actively randomized, and it is the sudden cooling of the randomized state to a solid stage again which locks the structure into its hard, "molecule frozen" state. At that point steel is very hard but it is also brittle, we would place it above R 60 on our standard Rockwell hardness test. It can be used in that state but only with care, and it was soon discovered that reheating it cautiously softens the hardness bit by bit. When a tool is reheated to red/yellow heat, and then allowed to cool slowly, even by sticking it into a pile of cool wood ashes, it will finally be completely softened, or "annealed" when cold. At this point it can be bent without breaking, twisted and tweaked, but to form it into a new shape it must be heated again and hammered while red hot. The old adage says: "The cardinal sin of the blacksmith it to hammer cold iron", since that produces internal stresses which later cause breakage, even if the material is reheated to red hot.
But by bit people have learned over the millennia how to harden and temper (soften to a desired state) steel. There is an exact middle-point at which the material has "maximum strength", which means reasonable stiffness without brittleness. A spring is a good example of this state, it must not snap on bending, and it must return to its previous position repeatedly.
Only a hundred years ago, steel was hardened under what a modern engineer would consider primitive conditions. The blacksmith or factory hand-worker heated the cutting end of a chisel to a bright red, plunged it into warmish water agitating it afew seconds, and then set it aside for "tempering". In order to temper it, he first ground or sanded the black surface scale off the tip a few inches back so as to see the colors appearing, and then applied heat behind that point, watching colors on the surface of the chisel progressively change as the heat traveled up toward the tip. The order of the colors was the key to tempering, since each oxided color had a specific range of temperature. First color to appear (the lowest temperature) was pale straw color, then a light straw, then light brown, brown, light gold, gold, dark gold, faint purple, and finally blue, giving a range of from about 400F for pale straw to 600F for true blue.
This was perfectly attuned to craftsmen's needs. The pale straw would be excellentfor a chisel which was used in soft to medium density woods, carving with a pushing action. If in harder wood or lightly tapped a medium straw to brown would be less likely to chip, while for real driving with a mallet, as in timber framing mortises, it would be better to go for a light blue. If you harden a screwdriver at the bit and then grind it to shape, you get a pretty good indicator of wear after using it a while. If "full blue" you will find it rounding over at the edges, but if pale straw there is a good chance that it will snap off on a hard twist. So like many a l9th century craftsman, you will harden to a good healthy "brown" and the screwdriver will keep its edge for years. ( We won't talk about the people who file a screwdriver tip to a V, they think that is sharp but we know it is a dull idea.)
A plane iron is a little harder to work with, since you have to get just the front edge hot, so clamping a piece of steel or aluminum about half an inch from the cutting edge would keep the heat down near the edge. Since such a thin piece of steel is more liable to cracking, I would plunge it into a bath of a cup of motor oil, which has a slower rate of heat transfer, and is often used as an alternative to water. (Remember oil quench is great, but oil can burn.) In any case what you are trying to do is bring the heat down from about 1600F to under 1200F in a few measured seconds interval. Water quenching gives more hardness, oil gives less if that it desirable. But tempering to a middle range, even on the soft side, is necessary for a plane iron, since it can hit knots which will crack a hard edge. So for plane irons, go for a decent "brown".
Most of the steel you will find in woodworkers tools is "carbon steel" so called, which you can identify by the characteristic spark against a grinding wheel. Carbon steel sparks go out straight, then divide clearly into clusters of bright yellow sparks, whereas any of the "tool steels" throw out straight patterns of dull red spark without branching or sparkling. Of course there are hundreds of specialized steels in common use, and many of the modern steels cannot be torch-hardened at all. If you do have to make a new part, for example a moulding plane blade, look for "water hardening steel = W1" or "oil hardening = O1" which can be handled in the traditional way. Highspeed steels, so called, need very special rates of cooling from a specific topheat, often in an inert atmosphere, with prolonged cooling rates, but I have hardened unknown steels from the junkyard successfully although from sparking I know they were not suitable. Test and try!
But there are a few basic rules to follow:
a) Never heat metal to the point at which it starts to emit sparks, since these are the carbon molecules departing from the steel, and you need carbon or the steel will not harden.
b) Never heat steel to be hardened in the forge, since even good blacksmith's coal will have small amount of sulfur which is death to hardening steel. In fact it is introduced into Free Machining Steel to make it cut more easily, of course losing strength.
c)If you heat your steel with an oxyacetylene torch, go easy because you want a heat of 1600F, whereas the flame is almost 6000 F (sic).And your torch must have a neutral flame, which means you adjust the acetylene until there is just a touch of a "beard" ahead of the blue cone, and then diminish it to "no beard", which is the neutral flame. Too much beard means too much carbon which will weaken the steel, too much roaring oxygen flame will burn out the carbon, so there is reason for caution here. Best have some who knows the flames show you --- or experiment and check the results!
d) Never try to bend or hammer on hard steel, which can shatter and fly into your hand or eye. But when heated red hot and softened in ashes, hard steel is ready for bending and forming. Some people use files for making tools, which is great so far as the carbon steel is concerned. But files snap badly, so beware.
In conclusion, heat treating certain woodworking tools as repair for overheated chisel blades or making a new tool from bought stock, is something which can be done by a person who knows the procedures I have outlined above, has access to an oxyacetylene or propane/compressed-air torch, or for small work even a propane flame directed against a carbon block (which retains heat and emits more as it burns). It is more than a little magical to see a piece of steel which is totally soft turn so hard that it can carve into the bar from which it was made, and when you heattreat steel you feel you are in the trail of a very ancient and very important tradition. But always remember to touch iron lightly because it can be hot, to wear glasses through the whole process, and if you learn the process well, teach someone else in the belief that this old tradition of the metalworking trades should be passed along.
The flat, steel "cabinet scraper" is one of the simplest but often most mis-understood tools in the woodworker's repertoire. Pick it up and it looks like nothing more than a 2 x 4 inch strip of thin steel to be used to scrape up the goo which paint remover leaves, but it is a precision tool which comes in many forms and does work which no other tool will do,
We often think of sandpaper in its myriad grits as the ultimate finishing material, we start with an aggressive 80 grit and work up to l80 grit, often pushing on in successive steps until we find 400 grit is really too fine for wood fiber although great for finishes. But just as many an old-timer knows that the best surface for gluing is freshly planed wood sliced off with a sharp blade, so in times past it was known that wood scraped with a broken edge of glass or the finely curled edge of a steel blade will leave a perfect surface ready for finish --- and this done in a few deft strokes. It is true, getting an even surface overall with scraping takes some practice, and not all wood responds equally well to the scraper blade. But scraping produces a fine and smooth surface like no other, since there are none of the sharp, projecting abrasive points which are what makes sandpaper work. A sandpapered surface seen with a microscope looks like a sawblade, the finer the paper the finer the saw appearance, but the scraper leaves a surface as smooth as the scraper edge, that is all there is to it.
You can buy from a tool house for a few bucks a scraper blade, but that is insufficient, because scrapers like people come in all sizes and shapes. You need a dozen scrapers in widths from an eighth inch to inch and a half, some dead flat, most with a lilt at the edges to avoid digging in, many with a very slight convex bow to feather out a one inch wide strip which you will use for flat work. So how do you get all these sizes and shapes? Of course, you make them up!
Get an old rusty saw which has good steel, if it is thinner at tip and back than at the teeth it is probably excellent old steel, but you can use anything you have at hand for a start. If you don't have a shear, get someone to shear up a handfulof strips cross to the blade for you. Don't try to handshear because the material is too hard, or cut with an abrasive wheel which will ruin the temper. Shear off the first half inch at the teeth, old saws often have some hardening at the tooth and this is too hard for the next process. At this point you have a dozen or more blanks, first thing is to touch the sheared edges to a belt sander to remove the burr which can cut your fingers, and round slightly the back corners. Now you are ready for the preparation of the cutting edge.
The traditional way is to hold the piece in a vise with half an inch sticking up, take a single cut file (with just slanting teeth on it) and drawfile the edge, which means slice the file across the work sideways, so the teeth have a smooth shearing action. This produces a dead smooth edge which is what you want, but in this case proceed with successive slices until you have something like a 15 degree angle. Now you will need a piece of half inch round steel which is very hard, to roll a curled edge off the top of the blade, it is this curled edge which does the scraping. Actually it is not scraping at all, it is shaving or even planing off a minute curl of wood from your surface, often less than half a thousandth of an inch. Scraping is perhaps the wrong word because it connotes a rough, tearing action. The Scraper is in fact a micro-planing machine.
I mentioned the hard roller for the edge, which is something you may not have at hand. I have taken one of the old steel knife-sharpening irons which came with carving sets, removed the deer horn handle, put the steel in an electric drill, and let it rotate again the worn belt of my (running) belt sander until it is smooth and polished all over. Since you want only half that length, you can make a deep groove around the middle with the corner of your grinder wheel, and then snap it in two in the vise with a pipe, but wear glasses and use care. Then you can put the original end back in the horn handle and give the other piece to a friend. (Another simpler way is to go to a machine tool house and buy a 6 inch length of 3/8 diameter "drill blank" which will be very hard, precise to. 0001" and hence fairly expensive.)
With this hard roller you will start rolling at the 15 degree and with each pass across the prepared edge go a degree or two towards the horizontal (perpendicular to the scraper). You will see a small curl forming, this is what you are looking for. If it curls very easily you have soft material which will cut fine but not last. However you can re-roll several times before drawfiling again. On the other hand, sometimes you find the saw steel is so hard that you can't get a good curl. In such a case use the procedure which I describe next:
Drawfiling works, but I find it much better to use the dullest, used belt I have on hand on my belt sander to shape the edge to the required 15 degree angle. While at it I can do two other things: First I can delicately relieve the corners so as to avoid digging in. Second I can make a slightly convex contour, so the actual cut is at the center third of my scraper width. This avoids digging and also gives a narrower cut, which provides more cutting pressure while giving me a decent-sized scraper to hold with both hands firmly. And I can also use the belt sander to remedy the matter of an overly hard material (as noted above). I hold the scraper firmly against the belt at 15 degrees, but continue pressing it until a faint blue color appears at the very edge, then stop immediately. (Look in the other essay on HEATTREATING if you want more about the color/temperature/hardness relationships.) This will soften or temper the hard saw material sufficiently for a good curl.
can consider the matter of what shapes you will want for your set of
scrapers. I have made up straights and curves for all sizes from 1/8 for
delicate contours, to a full two inches for large surfaces. In some case I
have planed a large mahogany board which I didn't want to entrust to a
planing machine, in this sequence:
Why do I find this so attractive? Because the grain is left clean of sanding dust, there is no powder of wood and worn abrasive particle stuffed into the natural grain of the wood, so when the finish if finally applied, the wood shows its micro-fiber structure through the finish in a sparkling display. If you ever wonder why fine old violins always have such a beautiful, bright finish on the maple back? It is because the old instruments makers used scrapers for the final finish, and over that they used clear varnish which could let daylight into the pores of the wood --- and out again.
One final thought: Holding the scraper with your two hands takes effort, and you get something like "writer's cramp" after a while. I found a useful way around this. Drill two holes in a scraper about an inch and a half apart, I suggest 3/16 holes with a really hard, perhaps titanium coated (gold colored) drill. Drill slowly but firmly with a drill press or the heat will harden the steel and then you will never go through. (I have a lever punch and used that.) Then take a hammerhandle, cut it to about 30 degrees on the table saw, and drill small holes for woodscrews to match the scraper holes. Thus you have a two handed handled scraper which you can wield with much more even pressure, and very little fatigue. If you drill your other scrapers to the same pattern you have the best of both worlds, a precision scraper and a tool you can use hard for hours.For scraping off hard varnish this is really a necessity, and scrapers are good for this too. But the real use for the Cabinet Scraper is not in the refinishing shop, it is a basic tool for the ultimate finish on a finely crafted wood surface.
Most woodworkers think of "planing a board" to mean running it through a power planing machine, and this does take care of the majority of our woodworking needs. But we should remember that the "planer" is really not a planing machine at all, it is a single side power surfacer, which grabs the boards with considerable pressure under a set of spring-loaded rolls, feeding it as it slides over a relatively short table (compared to a jointer) under a set of rotating knives. Since the table is short, the board will come out with about the same curvature as it had when it went in. And since the rollers press a board flat across its width while cutting, when the board emerges it will spring back to its natural cross-curvature. For ordinary work this is not important, but if you aredealing with a valuable piece of wood, and looking for a finished board which is straight and really flat you cannot use the "planer" by itself. Good shops always run work over the long-bed jointer which gets the bottom side straight, then the planer does what it is designed to do. It cuts the top side smooth and ensures that the work is of even thickness. It is for this reason that the machine is called a Thickness Planer, it is designed to cut to a given dimension of thickness.
But if you have a board wider than 12 inches, you will have a hard time finding a jointer which cuts wide enough. And if your board has cross-curvature, your thickness planer will simply not do the job. So here is a case where you might consider going back to the old-fashioned time-proven method of "planing down your work by hand". Last year I was looking at a beautiful six foot long mahogany board which had a slight cross-curvature, it was 24 inches wide and had been aged in my shop for nine years so I knew it was stable by then. I didn't want to take to a mill which had a 36" planer because I knew the board would spring back after it left the rolls, and I was also nervous about losing too much of the thickness in the process of getting a clear surface, so I figured to do it by hand.
First I had to have a straight edge I could trust, so I ran two six footstrips of hardwood plywood across my long-bed jointer to get a reliably straight edge, and was satisfied when the two edges matched up light-tight. I cut one in half for convenience in working the cross dimension. Now let me pause for a moment a run through a description of the various types and sizes of planes which one can find at hand, and then return to my experience with my mahogany plank.
Hand planes come such in a bewildering number of sizes and shapes that it is easier for the collector to know which ones are valuable and which not, than for the user to know which to use for a given job. The small Block Planes with a length of about 7 inches, the little fellows which fit the grip of your hand without a handle, are used for working down surfaces for finish, but they are not intended to make boards "plane", a job reserved for the longer member of the family. The common block planes are the low angled ones like the Stanley 60 series, when properly sharpened to a razor edge they will work cross grain at the end of a board reasonably well. The Stanley 9 1/2 or various Sargent models have a slightly less acute cutting angle, work well on flats and edges but are less effective on cross grain. Then there are the common models with a higher angle to the blade which are fine for general work, excellent for edges and bevels, and in some ways better than the low angle plane for glue-up work since they leave a fine, open-pore surface for gluing. But they balk at any across the grain work.
Also there are wood Block Planes, made from a solid block of wood, whence the name. These are the old-fashioned style, with wedged blades which must be cautiously tapped into place for adjusting the cut. These are larger than the small cast-iron planes, they are nice to feel in the hand, they have a touch of history to them. They rub a wood sole smoothly on the wood work, and are not to be despised. They are fine for the leisurely woodworker who has a feel for his tools and knows how to tap a blade into place, but not for the man in a hurry.
Next in size are the Smooth Planes, a little larger than the Blocks and averaging nine to ten inches in length. But there is a vast difference. The blade angles are generally about 40 degrees, they have a tall gripping handle at the rear and a hold-down post at the fore, they are used for smooth finishing work to be ready for sanding or scraping down. The Stanleys are a good example of the range, (excluding the rare #1 Smooth which sell high for collectors) but the '#3 and especially the #4 are found easily and after their bases are lapped out to counter shrinking of the cast metal over the years, they are the most useful of the smaller planes. (But they will not do well in a tangle of upstanding grain, where you will go back to your very low angled Block Plane to slice through it decently.) There are many other brands, all virtually identical in use and performance, don't be a snob and ignore a nice, clean Craftsman from the '50's, a Sargent or an un-named interloper. If the base is flat and the blade is there, they will all do the same work with the same hands.
Now, in this same class are the so-called "transitional" models, which nobody seems to understand or want. They have a wood base onto which is screwed a nice cast-iron plate which has a blade holder and screw adjustment about the same as on an all-iron plane. They responded to the notions of older craftsmen who didn't like the idea of rubbing iron onto their woodwork, possibly because iron in an unheated shop quickly picks up mild rust which can rub off as red and appear in the new water-based finishes. Or it may have just been a whim. But these planes have wonderful possibilities. I made a long variety of a Transitional with a long carefully prepared board into a shooting-board-plane, moving the handle to the side at an angle, and it serves a harpsichord maker perfectly for edgeing the sections of his soundboard for gluing. It is truer than a power jointer and leaves the grain perfectly open for glue. There are other conversions for Transitionals, with a board screwed to the side accurately, they can make an edge joint at a perfect right angle just as well as a power jointer, and you never have to worry about the fence setting, since it is fixed at 90 degrees!
Going to the next class we find the Jack Planes like the Stanley #5 whichare used for hard work, removing stock fast and leaving finish to the next stage of work, although when sharp they will finish fine. Jack planes run about 14-18 inches long, they will obviously not dip into the low spots but cut the highs well enough considering their medium length. In style they are designed as bigger cousins of the Smooth planes, the parts are just a little larger and heavier, the blades are wider, and they are build stouter for heavier work. Their larger brother is the ForePlane (the Trying plane in the UK English terminology), which runs pretty near to 18 inches in length, of which the Stanley #6 is a good example. I really don't see much useful difference between these two sizes, there is only a couple of inches difference and they do the same work equally well. Weight might be the main difference, and unless you are trying to line up a complete Stanley Series, I suggest having the one or the other depending on what you find around.
You know the little stamped iron lever which sticks out over the handle to shift the blade sideways on iron planes? If you find a plane without this level and it is cheap, get it because you can sell it to a collector as an "early model" pre-lateral. But if for your own use, you want this adjustment which comes in real handy.
Now remember that there are solid-block wood planes in these two sizes galore, running from about 15 to 20 inches, and although they take a lot of care tapping the blade into place accurately, they have one great advantage. When you first get one which looks solid without deep cracks, after removing the blade and wedge (!), run it over an accurate power jointer with a very light cut. Now you will have a Perfect Sole, accurate to a thousandth of an inch, something which you can't get with an iron plane, without a lot of hand lapping or machining. (I don't recommend truing up an iron plane on a surface grinder, because the plane inverted is a devil of a thing to chuck up solidly. And the least bit of heat will warp the iron, so although true when finished, it may be cupped slightly the next week.) Wood planes will warp a bit, but very slightly in well aged hardwood, and after the first jointing, a little fine sanding on a plane surface like your table saw top, with fine sandpaper taped in placewill restore it.
Jointer Planes are the longest members of the family, they generally run from 22 to 24 inches in the iron models, Stanleys #7 and the two inch longer #8 are good examples. The name implies that they are to be used for making up glue joints, which they will do well for planarity, but since they have no way of assuring levelness when planing other than your eye and hand, they are not really reliable for this work. The power jointer is always better (if sharp, to avoid crushing down open grain which the glue needs) and the fence is set accurately. On the other hand if you want to hold to hand-work, get a long solid-wood bodied jointer plane (the sizes go up to 32 inches in length, but use an 18 incher for this) joint it on the sole and then one side square to the base, and screw on a flat board to maintain squareness of your glue surface. (Rabbit out a section of the board to allow for the width of wood on the plane beside the blade edge. Or leave the board straight and glue on a 1/4" strip of plywood.) If you are right handed put the board on the right so you can press it hard against the board, or vice versa.
But I have a much better use than edging for jointer planes, which is working the whole surface of a board to flatness, and this can be done without removing any more of the thickness than absolutely necessary.
I want to mention one kind of plane which is hard to find, which you can make for yourself without much trouble or cost. This is the small Rabbit Plane which you are always wishing for to clean up or enlarge a rabbit which has been sawed out on the table saw. I suggest taking a 3 ft. piece of hardwood, perhaps 1 1/4 thick and 3 inches wide, and cutting out on the tablesaw a half inch deep slot for a half inch wide blade and its locking wedge. If you cut the support angle to 40 degrees and the wedge angle to 35, and clean out the material between with successive saw cuts, you will be ready to fit in your blade and make up your wedge to lock it. I suggest sawing the wedge rough and belt sanding it to a perfectly tight hammer fit. By cutting this from a long piece of stock you can use your table saw miter gage, you have enough material to hold onto, to cover some errors, and to make a second plane for the other direction. When done leave enough for a carved knob, a squirrel tail as many older ones have, or simply cut if off flush. It would be good at this point ot continue and make another plane going the other way, you always have changes in the grain or have to work to the opposite corner. For the blade, get a length of 1/2 x 1/8 in. WI or O1 (water or oil hardening) stock, and read my other section on hardening and tempering steel. You will want to sharpen the blade on bottom and side of course, and a sheetmetal screw threaded all the way up aimed at the edge of the blade will adjust it micrometrically from the far side. A pair of these planes is indispensible, the antiques Stanleys in a pair are astronomically costly, and these will cost you only an hour or two and a length of tool steel.
Now let me go back to my original project of hand-planing out a wide mahogany board.The board I had on my worktable was six feet long, five fourths thickness, with about an eighth inch of longitudinal curve and just a little twist. But there was almost an eighth inch of cross-curve which is what made me decide to do the planing up by hand, since I wanted the thickest dimension I could come out with for my table-top. The surface was the original mill cut, rough and hairy, so the first tool I put my hand to was the scrub plane
This scrub plane was a solid block plane about nine inches long, its sole was two and a half inches across with under an eighth inch roll, and the blade was matched to this curvature. I tapped the blade into a light cut, and started out removing the obvious high areas in long, fast sweeps at about twenty degree across the grain. Since the plane cut a chip which was paper thin at the edges of the cut there was not much chance of tearing. I went at it with energy, first working down the high center and turning the board over onto two strips, I started cleaning down the high edges. I was surprised how fast this went, in ten minutes I had a relative degree of flatness established, although the surface was hilly from the scrub plane cuts. For this kind of preparatory work there is nothing like the scrub plane, because it lifts its chip from the middle and simply can't tear out at the sides. Clever, these old plane makers!
Now I made the big jump to a long "jointer" plane, again a solid wood plane 30" long, I chose this long one because I wanted to reach right across the board, working at an angle of about 40 degree. I tapped the blade into position with the right side of the blade barely cutting and the left side making a very modest chip, then starting at the right side of the board's length, I proceeded down the length with 40 degree angled cuts right across the width. I kept the cuts close, just chipping away atthe length carefully, and in a few minutes I was down at the other end. Now I turned the board around and did it again right to left so as to cross-pattern my first cut. With the two high edges up it was fairly automatic cutting, but when I turned the board over I had to be careful to keep my planing on that high center. So I went to my Stanley #7, which was lighter and easier to work with its two handles, I balanced the blade tilting it as above, and worked down the center crown. When this was almost flat, I went back to the wood-bodied Longfellow, working down from right to left and this time continuing until my cuts just about reached the edges. Again turned the board around and cross-sliceed at the reverse angle.
Now I checked with my straight edges, marked the highs with soft school-chalk which don't dull blades, and worked these over with my #5 until there wasn't much need for chalking anymore. At this point many people would give it a once-over the belt-sander, which would do a good job except for two things: Wood powder would be crushed down into the open grain hiding the glory of the finish, and also there would be particles of the abrasive worked into the grain. So I kept going with the planes.
At this point it was time to smooth out the small highs which remained, so I went at it with a Stanley #4, first sharpening the blade on the belt sander to a nice even edge without the roll you often get with a stone, and polishing it on my hard-felt wheel with abrasive rough stick. I always relieve the corners of a plane blade used for fine finishing like this, just stoning off a tad so the blade doesn't leave one of those edge marks which are so hard to get out. Now I went over the whole surface, smoothing with this "smooth plane" in its proper function. (The Smooth is often nothing more than a dull-bladed tool thrown in the carpenter's tote box for use on a sticky door edge.) In a few places I had to watch where grain wanted to come up a bit, so I switched for those areas to the low angle block plane (my Stanley #60) working cross to the curly grain so as not to lift it, just shear it off precisely.
At this point you would be ready to sand it. I decided which would be the down side for my table-top and went over it with the random-orbit sander at 180 grit, then 220 grit, and it looked just fine. But I wanted to see if I could do better for my top surface, even if it took half an hour more, so I went to my scraper box and selected one with inch and a half width, corners relieved a tad, re-rolled the edge and did a final finish just by scraping. Much old furniture was done in this way, by leaving thegrain open and un-cluttered with wood powder. The light which penetrates a clear finish has a way of getting caught in the micro-traps of the grain and reflecting outward in a magical glow. This is similar to that unmistakable brightness you see on a bluejay's feathers, the result of light poured over micro-traps of the feathers, the size of these minute apertures measured in millionths of an inch, generates the color "blue". There is much to be learned about the way certain wood radiates light, and I suggest experimenting with scraped as compared with sanded surfacesto see what you can find out.
Was all this work with the mahogany board worth while? Yes, and there are three reasons:
First, I was able to get the maximum thickness out of my board by proceeding carefully and selectively. This took time but I preserved my material, whereas from previous experience I believe that if I had taken it to the mill where they do have big equipment, I might well have ended up with a much thinner board. They are in business to turn out work fast, a quick adjustment could cost me an eighth of an inch gone to chips. Here the consideration was for safety of my material.
Second, I knew that such a wide board would be pressed flat by the rollers and would curl back when the work came out. There is no way out of this dilemma.
Third, the finished surface of my carefully worked board has a touch of handwork about it, it is in fact not as flat as a machine could make it. There are very minor shifts in the surface which you can't really see in the reflecting satin finished surface. But the table-top is somehow perceivable as a hand-made object, there may be a softness about it which reminds you of the way it was made.
Oh yes, one thing I forgot to mention. When I cleaned up the shop and swept up a basket full of paper-thin mahogany shavings, and put the Stanleys back on their shelf all lying comfortably on there sides as they should be, and finally set old 32 inch Longfellow pridefully back in a high place to wait for the next time I had to call on him, I felt a sense of pride in doing that job in an historical, old-fashioned way. And at the same time I noted to myself that I had really done it carefully, correctly. The time spent seemed to have passed in a flash, the work was totally engrossing and totally enjoyable. It was the sheer pleasure of using both mind and hands, and the ancient business of working with wood.
When someone asked me recently "how to file a saw", I replied that I couldn't really get that information into an email, and in fact I wasn't sure I could explain it at all. I don't think diagrams and drawing would be of much use for this, and finally suggested to him that he find someone who does filing well, and see if he could watch him for half an hour to get the hang of it.
Since then I have been wondering if I could put this fairly involved process into words, so I decided to have a try at it and see if I could at least make the basics coherent to a person who wants to file his own saws. The process is more complex than it seems, and only practice will make you into a decent saw filer. But there is a reason to file a handsaw. The hand filed saw is a special tool, it cuts with a crisp sound, the rhythms of handsawing is good for the soul, and it will do some things which you cannot do with power tools.
But first you have to get a few saws, put the good one aside and work on your yardsale buys until you get the process down firm. The best saws were made from the l880's on, with a very slight taper of the blade in two directions. First the blade got thinner from the tooth edge back to the top, and a really good saw was also thinned from the handle end down to the tip. Look at a good saw and you will see that the top edge of the tip end is often quite thin. This makes the saw lighter to the hand, and was intended to minimize whipping as you run through a cut. (The little nib on the top side at the end is something nobody is quite certain about, perhaps best consider it a mark of a high quality older saw.) The handle will be of a good wood, often decorated with incised cuts and detail, but always nicely shaped to fit the hand and fingers well. The way the handle is made and set on the blade does affect the "feel" of the saw in action.
Some cabinet backsaws (the ones with short square blade and a steel stiffening back at the top) have a blade ground thinner toward the top and for fine work they do not require "setting" of the teeth; but most saws must be set before the filing can begin. A saw-set is a small grip- operated tool which is used to very carefully press alternate teeth right and left, giving clearance to the blade which would otherwise stick in the cut. I remember my Dad always rubbed some cake soap over the blade before starting a cut, now I realize our saw didn't have enough set and this was a simple say to avoid binding. But better do it right!
First level the tips of the teeth. You can get a little device designed to level tooth tips with a section of file built in, but you can do it just as well with a single cut file (one with single angled cuts..... for saw work avoid trouble or cross-cut files which make points rather than flats in the work.) Holding this perpendicular to the blade, which you are clamping in a vise, you slide it flat and lightly down the tips watching until most of them show a very small bright spot. You don't have to get every last tooth, must most should have a bright tip. Now you can start to set the teeth.
Try this first on one of your scrappy saws, best experiment down at the handle end where little sawing will be done, so if you break off a tooth or two that won't ruin the saw for use later. Good saws with properly hardened teeth tend to snap a tooth if over-set, so be sure to go easy. The SET should be just about enough to see teeth just peeping up, if you hold the saw sidewise and look across the blade toward a window. If for rough work you can make the set greater for easy cutting, but the cut will tend to wander more. Here as everywhere use caution and judgment. The amount of set is determined by the top gage on the sawset, and if it has a moveable anvil, by adjusting it around to the right point. You can often pick up sawsets for a dollar or two at yardsales, I suggest getting a few to see which of the old ones have features which the new one at the store lacks, but when you get used to them they all do the same thing. (There is one exception, the various stamped steel old Taintor models, which will do the fine teeth on a backsaw much better than any other device, since they have a double-pinching action which ensures accuracy in the small sizes.)
Now let us assume you are filing a crosscut saw since this is the most common use of a handsaw. (We discuss the rip-saw later...) You are going to do the filing with a triangular section file, one with a width of 1/4 inch or so is best, and again it should be a single cut file. I always push the tang end firmly into a cork from a winebottle to give my hand something comfortable to press against, our you can drill a piece of wood and tap the tang in. You are going to make some hundreds of cuts, so it is important for your hand to be comfortable.
OK, with tops level, teeth set to the right and left, now you are almost ready to start filing. But first we have to have the saw in a firm grip or it will chatter under the file which ruins the cut. I usually grip the saw in a machine vise and file only the section firmly held in the 5 inch width before moving it along; but if you use a smaller vise you might hinge two pieces of plywood, about ten inches long, together with a slight gap at the bottom and use this in your vise to grip the saw. Your Record style woodworkers' vise is useless for this, but there are nice old saw filing vises of various styles which you might keep an eye out for, since they come up from your table about the right distance for good filing and are adjustable for angle too. Speaking of filing height, I suggest about two inches higher than your elbow as you stand ready to file, and I would always file standing for the best file control.
Now we come to the part which is hardest to define. With the saw handle to your left, you select the first tooth which is pointing (set) to the left, that is away from your right hand if you are right-handed. (If not reverse this....) Without filing, set your triangle file into the V or gullet, and get a feel of the way it rests. You will note the tooth angle is canted toward the tip of the saw somewhat, this is the "rake" which makes the cutting aggressive, in filing you want to keep the rake of the saw as it was made. Now notice that since the tooth you are going to file leans to the left slightly, you will want to bring the tang of the file slightly toward the tip of the saw (right), so when you file the backside of the selected tooth, your cut puts a bevel on that tooth.
OK, now try lightly but firmly, filing the backside of Tooth 1 with stroke angled and also lower your hand about the same amount, so your cut is perhaps five degrees up, and at the same time, five degrees across with a left pointing angle (for a left set tooth). Try it lightly and see if you are matching the face of the tooth on its backside. Now since the angle of the saw between teeth is 60 degrees and your file is also the same angle, when you cut the backside of one tooth, you will be cutting the frontside of the tooth behind it. That is why I said to angle the cut, we want the previous tooth to have a front face angled so it will cut in aggressively. But of course it is the front side of the tooth which is the important, cutting side, so pay close attention to that one first. Since the same file stroke does back-of-front and front-of-back, you will be progressing along the saw switching your angles on each successive tooth, and both tooth-angles will be filed simultaneously.
How much do you file and how deep do you want to go? Now that bright tip of the teeth I mentioned before, is what you want to keep your eye on, you file until that spot just about disappears, maybe one light touch more. This gives the perfectly sharp point which you must have for clean sawing since this is the first contact of saw to wood.
Do a few teeth and check it this way. Looking down at a few filed teeth, a tooth set to the left should have a backside against which the file nestled nicely when canted slightly to the right and down a few degrees. This must also nestle nicely into the face of the previous tooth (all pointing to the right...). Now looking straight down, you should see that left-set tooth has a shear angle, by which I mean that the cutting edge on the left is angled back to the other side of the tooth, and the previous tooth will have an opposite angled face away from its cutting edge. Put more simply, each tooth wants these three things:
1) Even leveled
There is a good test for all this: If you can see little V's as you sight along filed teeth on the top of the tooth row, the filing was done right. Even better, if when you finish a section or the whole saw, if you can slide a sewing needle down the row on the V's, they job was really done well. The needle test is not for beginners, don't try it for a while, but you should be able to see the up-pointing AND side-slicing appearance of a group of teeth you have just filed. If this looks right, go ahead, if not go back and rethink the process from the beginning.
Most of the work done in a modern shop with a handsaw will call on the crosscut saw with six or eight points to the inch. But the ripsaw is still needed if you have to make a cut parallel with the grain, since the crosscut does not deal with this situation well at all. The ripsaw generally has four teeth to the inch, the teeth must be leveled as noted above and set to a slightly greater angle than the crosscut to avoid binding, since with-the-grain cuts in a board can bind as the board changes shape. The main difference is that the filing on the teeth is done straight across, so the front cutting face and the backside both have a flat face, which is perpendicular to the length of the saw. The reason for this is that when cutting with the grain, the main action is chiselling out chips and throwing them out of the kerf with each stroke. Each tooth in a ripsaw is like a little chisel, chopping into the endgrain as it proceeds. This is far better than for such cuts than the crosscut which is designed to slice across grain lines with the pointy-angled teeth, which would be slow work in a longitudinal cut. Nowadays most people use the table saw for the ripping, but if you find a nice old ripsaw around, get it and keep it for incidental use someday. It is also much easier to file and keep tuned up than a crosscut, since the file strokes are all level and easy to do.
Review: Most if this is fairly logical and simple, but getting the side- and up- angle at which you do your filing is a hard thing to describe. Let me go over it again. I lay my file between a tooth that is "set" to the left, that is pointing to me with the saw set in a vise or holder, with the saw handle on the left. I move the file tang off from perpendicular to the saw, a few degrees to the right and lower it about the same amount. Then I firmly hold the file in right hand with left hand on the tip, and do a straight stroke all the way through. If just starting, I see if the front and back faces of two teeth a filed clean and bright, I usually take two or three strokes. Then I go to the next tooth on the right and repeat the process, this time moving my file tang to the left, still lowered, and do another tooth.
Now that I have done two V's or gullets, on the front and back of a tooth, I should see if the bright point on the top is still visible. In practice I always go down a dozen or more teeth, then go back and file a little more until the tip vanishes. But the basic idea can be seen on a single tooth: Front filed clean and keeping original front-raked angle, with a shear angle toward the cutting side, and top point just about gone.
So much is for theory and the ideal result. But as soon as you get the hang of it, you will want to move along fairly fast, and you run into another problem. It is fairly easy to do the tooth which is "set" away from your hand, but when you start the next tooth, there is usually an unpleasant chatter from the file on the work, and also your hand has to be held up, the inverse of the previous down. But you do have choices:
You can reverse hand positions and file from the other side, other hand down, in other words the performing opposite actions from the opposite side. This does remove the chatter since you are filing into the angle you want rather than against it. But it is most inconvenient, you can try it at the start just to get the ideas firmly in mind, but I do it differently. I go down alternate teeth on the saw doing all of them with two strokes on a saw I am restoring, then turn the saw around in the vise and go the other way. By this time I have a clear view of the angled faces alternatively going right and left (I am sure to check the angles as "outward shearing forward") and I can go back and do what is needed to bring each tooth to a needle sharp point.
When you are doing a saw which you have done before but needs a little touching up, much of this is not needed. You know the tops are level, and the teeth are already set, you have the feel of the angles, so you can run down the whole set of teeth with a couple of light strokes of the file in ten minutes or so. What is important is having a good saw to work on (after your experimenting stage!), getting all the angles done right in the first place, and then being familiar enough with the filing process to go right at it as if you were an automatic filing machine. The one thing you will always be watching is the disappearance of the tips, other than that you can be thinking of something else, whistling a tune or enjoying the rhythmic motion of your arms as you do a good job to perfection.
Nobody seems to use steel, non-carbide circular saws any more, but if you have some good steel relief-ground saws from the old days, and want to use them for their smooth cut and narrow kerf, you can use most of the technique from the handsaw on these tools also. Setting the teeth is done the same as for a handsaw, most sawsets will work on a ten inch blade well enough. The main difference is in the topping of the teeth, which is done by putting the sawblade on the saw arbor backwards, and then very cautiously touching a piece of an old grinding wheel or a stick made for this, against the rotating blade. You just touch it evenly and straight across with a few light kisses, stop the saw and see of all the teeth show a similar circumferential flat, actually the less the better. After this the blade goes to the vise or holder and for rip you file tops at a relief angle straight across till the chisel edge just disappears. For a crosscut file the same way but at a slight angle each way, so the cutting tip enters the wood at a lightly side-raked angle. Since you have power, you generally don't need to adjust the front angle of each tooth, if you do it will cut more aggressively but get dull faster in hard wood with its sharper "angle of acutance". For really smooth cuts I have cautiously held a flat stone against the rotating tooth edge to knock off any slightly protruding tooth points, and this can give an almost polished finish without the cost of a high-value carbide blade. But here much caution must be exercised, and for all these rotating blade operation, mandatory GLASSES.
When someone says the phrase "Brace and Bit", you will probably hear the two words as connected to each other like "Laurel and Hardy", a natural pair which can only exist in the symbiotic state. What comes to mind is the old-line craftsman in his comfortable, wood walled shop carefully turning the brace crank with his right hand while his eye aligns the augur bit with the workpiece held in the old-fashioned all wood carpenter's vise reaching down to the shop floor. Or it could be someone in our time thinking with pleasure of the reassuring old days, with time worn tools in his hand and a sense of craftsmanship which precludes power handtools, the table saw and half horsepower drill press.
I think I can sever the brace from the augur bit with profit, and find some new says to use the traditional augur bit to do things which cannot be done with any other available tool. But first I would like to delve back for a moment into the history of these tools and clear the boards for action, as it were.
Until the beginning of the l9th century and the Maudsley screw cutting lathe, all screws were made by hand or turned out with crude hand-operated jigs to be cleaned up with the file. Drill bits were in the same undeveloped state and a round rod with a deep groove in each side, tip ground to two cutting edges and hardened, could be used to bore holes. In fact until around l900 there were still made "Farmer's", or "straightaway" bits with no helical twist to remove chip. But some bright fellow saw that you could take a flat strap, heat it red hot and twist it into a shape which would pull wood ship out of the hole as the tip did its cutting action. That was, after all the main problem in drilling wood, the chip bound in the hole, and if you didn't get it out it would burn the wood, overheat the bit and ruin its temper. So the "twist drill" soon became a necessary part of the cabinetmaker's toolbox.
By the middle of the l9th century the AugurBit twist drill was fully developed. The best ones had a twisted flute deriving directly from each of the two cutting lips at the tip, as in the Russell Jennings pattern which soon became common. Since such a bit required considerable pressure to work into hard wood, a tapered screw was designed for the tip between the cutting edges, which would pull the bit into the work with each successive turn, a self-feeding device which made turning the brace much easier. A vertical knife-edge stood up at the edge of each lip to cut the fibers of wood cleanly just before the cutting lips sheared away the wood inside that incised circle, and this was the touch which gave the augur bit design its great boring precision.
The twisted "flutes" for evacuating chip were usually about five inches long, the expected depth of a common hole, but some could be a foot or more in length for deep boring. Since the sides of the flutes were ground true, they not only transferred torque from brace to cutting tip, but also served as a guide in the hole providing considerable straightness. This is important in wood which has a great deal of deviation of fiber orientation and localized hardness.
At the driving end, the problem of how to grasp this bit, holding it straight while turning it to cut, was early solved with the square-tapered driver. This could not only take torque in the cutting operation, but since it was tapered it would keep the bit in good alignment with the work. Now, coming back to the brace, all that was needed there would be a female tapered receptable to match, into which the augur bit driving end would be jammed and set with a knock from a mallet.
Through the early years of the l9th century Braces were made of wood with a four inch crank an integral part of the stout hardwood board it was cut from. But since the grain would be weak between the hand crank and the shoulder-to-bit line, brass plates were screwed into the wood at the weak points on both sides, and a screw perhaps added at the square bit holder end to hold the bit in place. These are the elegant brass-finished antique braces which you see at tool dealers shows for hundreds of dollars depending on date and maker.
They are beautiful to look at and handle, but poor in concept and basic design, and were quickly made obsolete by the new ones which were nothing more than a bent piece of 7/16 rod going from shoulder to hand-crank and back to the bit line with a tapered square little receptacle for the bit at the end. These are often called "Ladies' Braces" because they are so light and delicate in design, perhaps even used by lady carpenters of the day. By the Civil War it was seen that the brace and its attachment to the then standardized augur bit was the problem, and the Spofford brace with its forged square taper right in the main forging, split and tightened with a strong wrench-able screw, was a simple and elegant solution. Since the drive end of augur bits was largely standard in size, it is remarkable that this split design did not become the regular "chuck". But Americans do love to tinker, and soon a complex chuck with a screw-down collar operating two "alligator jaws" kept apart with a spring became the working end of every brace made thereafter.
But that was not all. A ratcheting device was added to the chuck end of the brace so you could work close to a wall or obstruction, and since you might have to turn the bit out of the work, it had to have a reverse actions also, and of course a lock-stiff so you could........ well, for whatever reason. The round shoulder rest would wear its thrust washer down in a couple of decades, so a thrust ball bearing arrangement was soon found necessary, and of course a loose handgrip on the crank to prevent calluses. Anything else? Oh yes, japan lacquering, and the nickel plate which was never good without a copper substratum, so then it went to chrome like the new ones at Sears. The Brace has gone through a long line of developmental design with some sales hype, and looks nothing much like the brass bound wood braces of two centuries ago.
On the other hand, the augur bit, which is what I want to talk about, has remained quite the same through the years. The screw lead-in was perfect as an idea, whether fine or coarse threaded. The little fore-lips were perfect for defining the circle to be cut and easing the shearing of the cut, although some bits were made with these lips below the shearing tips to give a flatter end to the hole. The double-helix was challenged by the Irwin type of single helix behind the two cutting lips, to give more chip clearance or to cut costs perhaps. But the tapered square driving end remained, presumably because all the braces ever made were provided with chucks of various sorts, but all receiving a tapered square. That's why I was saying at the start, the two were early grafted together like the pair of a comedy act, and have never been seen apart.
Now let me change direction and raise some points about the drilling of wood, which is after all a most variable and unforgiving material --- incidentally produced by trees for a purpose entirely different from our uses. Hardness can range from soft pine to hickory, grain can run straight, screwy or (worse for us) directly into the direction you want to work as "endgrain". Into this most variable material we want to bore holes of exact width for many of our cabinetmaking operations, some may be shallow but many of them have to be quite deep. If a hole is bored to twice its diameter, there is usually no problem clearing out chip, but go twice this and the problem is clear. Drill a half inch hole to a depth of five inches and you have a real problem, unless you are using a drill specifically designed for this operation. The augur bit was clearly made for this, it does clear out chip very well indeed.
But the augur bit with its two little fore-running blades to sever fiber ahead of the cut, is a very fine little boring precision machine, if properly used. The body of the fluted section is stiff and guides the cutting lips in the hole, and this is clearly your best, proven tool for deep hole boring.
What else is there available to do this work? The ubiquitous spade drill which is cheap enough and can tear out a hole in a hurry is too rough for any fine work. I have been able to tame it somewhat by grinding a bit of an angle ahead of the face which is doing the cutting, but this is a minor improvement on a bad design. But worst is trying to drill a deep hold with a spade drill, which will pack up such a ball of chip behind its working head that you may not be able to pull it out without tugging or reversing.
What else is there? Woodworkers often buy or even make out of standard metalworking drills a brad-point type, which has a point at the fore to keep the work centered on changing grains, while grinding some of the cutting lip low provides a tip at the edge to sever fibers ahead of the cut. The cut is actually better than a metal drill unaltered, which will wander terribly in wood, but not real good boring bit after all. And what do you do for the larger bores, a one inch bit of this sort with a quarter inch shank on your 1200 RPM electric drill?
Now at last I can approach my point:
I am going to mentally scrap the Brace, and concentrate on the highly refined and developed Augur Bit as a tool worth re-appraising. It has several unique abilities: It will bore true diameters determined by the actual bore at the cutting end and the way the pre-cutting tips are designed to aid the shear. It will bore deep holes because its efficient chip removing flutes will continue to work without stopping until you finish the depth of a deep hole. It will bore straight holes because the flutes guide the bit in the hole as it is being made.
Someone one said that the most dangerous single part of an automobile is not what you would think, but the nut behind the wheel. I am afraid that this is also true of boring precise, deep holes in cabinet wood. It is the man (or woman of course) holding the brace against his/her breast with one hand, while cranking the brace vigorously with the other hand, and still trying to eyeball the whole operation so as not to deflect the turning bit from its natural boring azimuth ----- this is what makes augur bit boring with a brace unsuitable for modern cabinetwork. The bit has almost everything needed for fine hole boring, but it has one thing more than needed which ruins the whole job.
I am speaking of the square tapered driver. That is the part which links the bit first to the brace and second to the brace operator, and that is where the accuracy of the hole goes to hell. But I have a simple suggestion:
Cut the square drive off!
Now you have a proven wood boring tool, which you can put in your drill press and drill a perfectly fine, smooth, straight and accurate hole. Or if the work does not fit the press, you can use an electric drill holding it firm and straight, or clamp up some jig to help keep it straight. But in any case, you start at your desired point, drill right in on one operation until you are done, and this single action operation will make a smooth and consistent hole.
But wait! Before you go chop off the squares, let me add a few details. That clever lead-in screw at the tip of the traditional augur is now a liability with a faster turning bit, it wil lead in far to fast now, so I always file off some of the thread on three or four sides, leaving the point central as a locator but with no pull. Then I have to check the straightness of the shank in relation to the flute.I chuck it in the drill press, turn by hand to check runout and with a light wrench twist, or often just by hand, I push the body around until the point stays near a center point. Some bits have been abused, bent in the flutes, the shank may be hammered up, then go get a better one.
Speed of any bit in a hard wood must be taken into calculation, if your drill press runs in slow belt at 600 RPM, that is fine for a 3/8 bit in hardwood, but fast for a 5/8 in the same wood. Again the deeper you go the hotter the bit will become, and at the first sign or heat or (worse) smoke, you have to go to a lower speed. Best way of slowing a drill press is to have a rotating shaft as the side with a large pulley fed by the motor turning with a small pulled feeding the drill press spindle. Sounds like a lot of trouble, but this makes possible feeding a half inch hi-speed drill into a strap of steel, something often necessary in making up a jig or attachment.
Working with a hand held electric drill, this is less of a problem, since even a light-duty half-in electric drill will usually run about 250 RPM which will be fine for any woodboring. And some have variable speed control. Check the drill nameplate for its speed, but there is latitude in there too, since your variables are type of wood, size of drill and of course depth of cut.
Augur bits come in sizes usually stamped in numbers from 1 to 16 representing sixteenths of an inch, on one side of the square driver. But many bits are somewhat off their designated sizes, some were inaccurate, other intentionally oversized for a reason. So when you want to see what size a bit will drill, you first take a reading across the head and lips with an inexpensive sliding vernier dial micrometer ($15-25), this will be the first consideration for size. Then be sure lips and tips are sharp and bore a half in deep hole to be checked with the inside jaws of this same micrometer. I have been able to make a bit cut a trifle smaller by carefully rolling it (hold securely) on my stationary belt sander, holding it longwise to the belt and watching the sanding marks to be even all around. This might be good for less than a sixty-fourth (.010) but no more.
Now you can take that box of old bits or buy some used one in the right size range, check and sharpen them with a small, thin file, and see what diameter holes they produce. I may want one for half inch, one a bit larger for a loose fit on a bolt shank, one just a hair tight for dowels which I find are always shrunk on drying. So I am saying that there are really no "bad bits" which cut wrong sizes. Somewhere they may or will be a reason for that size, tag it and put it away for future need.
Then you find a bit which has no screw point, but that one can be used to finish up flat a special hole where you don't want the ring from the tips. I even have some with round shoulders, someone wanted a hole with rounded contours at the bottom edges.
What about drilling really long holes, like eight or ten inches or more. Well, there are long double twist augurs, some made for use by electricians and others of higher quality intended for just such a use. If the work can be spun in a lathe, the bit can be chucked in the tailstock and slid by hand into the work. You can bore first and turn on the lathe later for a balanced piece. One of the nice things about shopwork is there is always a new way to do something which you or someone else will come up with. This can be even seen as a model of evolution.
Standard augur bits without their drive squares, can be used in stationary machines turning slowly, or in handheld electric drills, to make smooth and high finish, diametrically accurate and deep holes in even the hardest cabinet woods. If we thought of the augur bit as tied to the brace and to the old-fashioned hand operation of brace-boring, we missed the true potential of this highly developed and remarkably useful hold boring instrument.
Reflective polish is more time-consuming, through a series of abrasive papers worked with water, and finally abrasive powders which are hand rubbed to a glossy shine. But much fine sculpture is intentionally left in a slightly rough finish, which is considered desirable in that it seems to connect the viewer with the artisan who brought the stone to that state of form. Just as bronze sculpture often shows the wax of the original model, lumps and fingermarks and all, so stone sculpture likes to shows the details of point and claw-work which crisscross every bit of its surface --- the mark of a maker who is signing with his handcraft signature on every square inch of the marble.
Marble is found naturally in many part of this country, it is mined extensively in Vermont,. Maryland, Massachusetts, Tennessee, Alabama, Georgia, Missouri, California, Colorado and Arizona. Each area has a special marble of its own, varying in texture and color from white to black. Marble is actually a limestone which is composed wholly or in large part of Calcite or Dolomite crystals, the crystalline texture being the result of extreme change of state (metmorphism) by heat and pressure over a long period of geologic time.
But whether marble is found in your area or not, there will be pieces left over from architectural work in the past, pieces and chunks in scrapyards and junk piles, house backyards and fields.. If you want to carve marble you will, with some searching around, find some nearer your place than you thought. Where marble is mined there is always a great scrap pile which gives just the kind of broken chunk which is the best starting point for a beginner.
There is a myth that old marble is almost impossible to carve, having been hardened by exposure to the weather. This is untrue although newly broken pieces may be a bit softer. Square cut blocks are not good for carving because you spend a lot of time getting rid of the corners, although this can be good practice if you have a square cut block to start with and patience.
Marble is really not difficult to carve, it is a crystalline material which breaks when a pound and a half hammer throws its swung weight through a pointed chisel into a given spot. This must be done at an angle which tends to lift off a chip rather than lose its force in the solid mass. You work to lift off chips about the size of a silver dollar and half an inch thick, maybe something like the shape of a half of a chocolate chip cookie. Watching someone who knows this technique helps, but with effort and patience you can learn it yourself, this kind of self-teaching can be a satisfying lesson in itself.
For starters you want a chunk weighing enough to stay still on your workbench by its own weight. A fifty pound piece should do for this, if smaller you will have to bolster it against motion. I have found legs from old dungarees filled with sand and tied tight at both ends make good bolster pads against motion. Your work table should be about 32 inches tall, it must be strong for obvious reasons relating to the safety of yourtoes, but scrap 2 x 4 (called cull at the lumberyards) nailed up with 16 d. (penny) nails will do nicely and cost you very little. Make the table three feet square as a good minimal workspace, and it won't tend to fall over on you. Scraps of half inch plywood at corners as gussets will make it quite rigid, in fact I would say that the first lesson to master in learning the craft of carving marble is to make yourself a table, to toughen up your mind and hands a little.
The tools for carving stone are very simple, but not available in this country where carving marble has never been a commonly practiced profession. It is very important to use the right kind of tools, which I will describe in detail:
The Hammer head is a piece of inch and a half square section cold rolled steel or any soft (not heat treated) steel. A wood handle about ten inches long is fitted through a hole drilled in this piece, which can be as little as one pound for a small or un-muscular person, or range up to two pounds for a strong and large man. The head can be of round stock which is easier to find and without corners won't catch your left hand knuckle as much. Carvers like the square one because it stands upright and won't fall over.I insist on the hammer head being soft steel for a particular reason, which I will explain:.
The chisel which is used most is the "point", a nine inch long piece of steel about 7/16 inch diameter which has enough points of carbon points in its makeup to be hardenable. Mild steel and cold rolled steel won't harden at all, so the choice of the material for chisels is quite important. Hexagonal bar of material No. l060 to l090 is what I use, although octagonal bar as used in Italy is a little more professional appearing but unavailable here. This chisel is worked with heat on the anvil by a skilled metalworker to come to slim point at the carving end, which will be hardened by heating red hot and plunging into cold water for hardness, after which is it reheated to draw the temper slightly so it won't break off. This point can be ground down several time until it goes past the area of hardness, after which it can be reshaped and rehardened.
But it is the conical end you strike with your soft hammer which is critical in this professional carving technique. The struck end is heated and formed by hammering to make a quarter inch little cone, which is hardened full hard. When the soft hammer strikes against this cone, the cone makes a small indentation in the hammer face which transfers ALL the force from the hammer through the chisel into the work. The hammer is virtually locked onto the cone end of the chisel, there is no sound other than a dull thud of contact, and I insist that this this is the only proper tool set to use.
I stress this because some people use a hardened hammer against the soft end of a chisel, since hard hammers are available everywhere and also soft ended chisels. First, striking this way makes a sharp, high pitched sound which is definitely bad for the ears. Second, the chisel end will flare over and sooner or later a piece will go flying off, possibly into your eye. Third, you lose a lot of the force of striking since the hammer glances off the polished chisel mushrooming end easily, bad sound, loss of force, and it may injure the chisel hand easily. Enough said, this is why I urge you to use the chisels I have had made up after the traditional Italian professional's style.
The point is the tool with which you start working, and often the can be the finishing tool as well. You can trace out delicate lines with the point, like the elevation lines on a detailed map from your County Agent. But once you have the general shape outlined, you can go over it with the "claw", which is a chisel hammered down to a 3/4 inch wide flat with five or six teeth ground into the front lip. This is a good leveling tool, and it also leaves its telltale pattern of parallel lines which shows that a good craftsman has had a hand working there.
For further smoothing out some areas, like the highlights in a painting, the "flat" is used. This is made like the claw but has no teeth at the front, just a hard edge. From here you can go to the roughest metalworking file you can find, a double-cut with criss crossed line rather than just one angle, since this will bite marble better. A large rasp-file from a faiier used on house hooves is great, even a worn one is valuable for this use. Worn bandsaw blades from a wood or machine shop cut in twelve inch lengths and tied together with wire at several places can make a fast cutting and cheap rasp which you can afford to scrap when dull.
Stones for working surface down are of various kinds, one about eight inches long and 1 1/2 in. square, rough faced and not expensive, is used by concrete workers,. Or you can ask at a grinding shop for old surface grinding machine wheels which can be cracked with a hammer to make hand size pieces, these are probably the best for working down a medium surface. I would keep away from too much sanding and polishing at first. The Wet-or-Dry sanding sheets form an automotive supply house are great for finishing but at fifty cents each can become costly on a big stone. Leave the stone natural under the chisel for a while, put it out to weather for a few months and go back to do some more when you have absorbed its possibilities.
There are several safety items which are mandatory. First, you must wear goggles which cover the side of the eye as well as front, since chips fly in odd directions. Second, if you are right handed, get an old pair of leather gloves, cut off the fingers on the left glove at the middle for a decent grasp on the chisel, and leave the thumb intact. Sooner of later the hammer will miss the chisel and land on the left hand knuckle of the thumb, leaving a painful reminder to always wear the glove when carving. Third, wear a simple respirator mask like the ones the dentist uses, if you are working out of doors, which is always the best place to carve. If indoors and dust floats in the air, you really should have a full duty respirator, or if you can't stand that gas mask look, wait till you can work outside. Also you won't have to clean up chips out of doors, they can become part of the landscape.
The question arises soon enough: What is the piece supposed to be? What does it represent? This is a bad question and there is no simple answer at all.
If you are thinking of carving a head or a body, while you are learning the basic technique of using the tools on stone, you may end in defeat. Heads are very hard to draw or carve, we recognize every human face we have ever seen but when it comes to describing or copying them, we find a great deal of the information is in the subconscious mind and not available for use right off. If you have drawing skill at representation, have a try, but if not sure, why not work with abstract forms.? In this last century pure shapes and forms have become part of our common artistic experience and you don't have to explain to anyone "what it is supposed to be". There is a clear answer to this which was used in ancient times by the Hebrews about their God:
IT IS WHAT IT IS
Don't be hesitant about making a cross or a star or a lozenge shape,
and if you start with a rectangular block,. why not carve a line all
around an inch from the edge, and then criss cross the area inside that to
make a doorstep? You can even do carving on a smooth cement walkway,
which prevents slipping in the rain and also shows someone with tools and
effort was working there. One man is known for his work with bricks
mortared into a basic shape which he wanted, let to set well for a few
months, and then carved all over with the brick lines at an interesting
I learned my basics of simple carving from a friend who is known internationally as a recognized figurative carver. This is unusual since marble carving in this country is rare and tends to go in the direction of abstract form. Not so Charles Wells, who does sensitive and evocative figures of all sorts, always with the touch of a master marking his work as special.
A few years ago I wrote up an account of how I first met Wells back in the '60's, and the two courses which he taught at Middlebury College years later. I wrote this up as a personal reminder of what kind of man Wells was and how my thirty students worked under his watchful eye, learning an ancient art in a totally different college oriented world. Some of the students went into carving marble, some stayed with art and transferred their learning into their own work, but none every forgot those remarkable months when beginners had a chance in the manner of the Renaissance studios, to work alongside of a Master.
For an inside view of a marble carving studio and what it felt like to
be there, take a look at my Essay on Carving