I came by woodworking by way of a passion for boats and guitars. But it was working in my first 'craft' shop, an upholstery shop, where I began my "apprenticeship". Later on, working in a piano restoration shop and then an antique shop cemented what I would be doing for the rest of my life.
Restoring antiques gives me the chance to do many things rarely practiced in today's furniture manufacturing—cutting tenons and mortises, dovetails, even French polishing. I am also afforded the opportunity to look at how some of the greatest cabinetmakers worked, getting under-the-hood, so to speak! I often remark that I have been taught by Chippendale and Sheraton and Townsend!
This notebook is a compilation of observations in my 40 years practicing the trade.
Often the wear on the lapped side of the blade is overlooked in the sharpening of chisels and planes. If you can imagine what the edge looks like when worn, it will show roughly equal wear on either side of the edge: the side where we grind and sharpen, and the bottom of the chisel. Having any kind of rounding on the reference surface (the bottom) will force you tip up the handle so the edge will bite. While this might be acceptable in a plane, this condition in a chisel makes cutting straight all but impossible. In order to truly sharpen the tool, the wear on both the bevel and the bottom should be gone. This can be done grossly by making the grinding angle quite large so, though it is taking only a small amount of metal, it is quickly grinding the edge back. Less heat will build up that might otherwise ruin the temper of the steel. After the wear is ground back the cutting angle can be restored by changing the bevel angle, grinding behind the edge, keeping the tip cool, until the desired bevel angle is achieved.
I think the bevel angle is the least important of the parameters of sharpening. Having a flat bottom surface is first. Having any grind that removes the dullness is next. Until those criteria have been met it is useless to proceed to the last element of sharpening—having the bottom and bevel polished mirror bright. Only in special circumstances are specific bevel angles important, i.e. end-grain, soft wood, erratic or contrary grain.
Flattening the bottom: I have tried most methods of flattening the bottom and I always go back to carborundum on plate glass. These are powders sold for grinding telescope mirrors and can be found with a little searching on the internet. I inherited my set from a violin maker who, Renaissance man that he was, made a telescope pretty much from scratch, using galvanized stove pipe as the tubes. I digress. The plate glass is as flat as you can get and can often be scavenged. If the bottom of your chisel is convex, that is, the middle bulges out, then flattening is so time consuming that, unless this is a one-of-a-kind tool, it is not worth it. Even a small bump takes forever to remove. I choose only tools that are flat or have a small concavity on the bottom. The flattening process usually starts with a fine grit just to see how much material needs to be removed and where. It is a fine grit when it polishes the steel. If it needs a lot of work then I will need to use a coarser grit. What I look for is an even scratch pattern or polish that goes across the whole front edge. Once that is achieved I use another piece of glass and polish the bottom with the next level finer grit. I continue until I get to rouge which will give a mirror finish. It is patient work. Use only a little abrasive at a time. Expect it to take a long time. But then, it is the last time you will have to do this.
Grind back the wear: Using the coarsest grit wheel on a tool grinder, establish a rather steep bevel and grind until there is no wear on the edge from the bottom. It will go fast because you are only removing a small amount of steel at the tip. Moreover, because it is only a small amount of steel, very little heat will build up. Since the tip has the least ability to dissipate heat, keep it cool, and let it rest between passes. Once the wear is gone, the desired bevel can be established. The grinder will now be starting at the other end of the bevel where there is a much more steel—a bigger heat sink. Work carefully up to the edge. Keep the steel cool.
Polish the bevel: Use a polishing stone 1000 gt or better to polish the bevel. Use the edge and the back of the bevel to establish the angle. Polish until the entire edge is polished. Then polish the same bevel using the finest stone, 5000 - 10,000 gt waterstone or a hard Arkansas. Lastly, lap the bottom of the chisel keeping the stone clean and working backwards so you don't run over the wire edge that will come off. You must keep these stones FLAT using carborundum paper on plate glass or diamond plate.
Plane blades can have micro-bevels on either side of the cutting edge because they are fixed in the plane body at an angle—the bottom of the plane blade is no longer used as a reference surface for cutting. A very slight bevel on the flat side can be made using the polishing stone eliminating the need for polishing the entire back of the plane iron. The ruler trick, attributed to David Charlesworth, requires putting a thin metal ruler (or any thin metal) on one side of the stone and placing the edge on the other side of the final polishing stone so the blade is elevated a smidge. The plane blade is passed back and forth until there is a continuous polished edge. This is especially helpful on old plane irons that have been pitted by corrosion where you need to abrade down to get unblemished steel. This method is not useful for a chisel which requires a flat bottom all the way to the cutting edge.
Marking gauges and molding planes have a tendency to wander as our arm motion is not uniform and the grain can pull the blade off the mark. This can be minimized by not trying to make the mark or cut in one pass. Rather, the mark or cut can be made in smaller increments, starting at the end of the cut and working backwards into your previous mark or cut.
In the case of a marking gauge, by starting the cut close to you and pulling the gauge toward you, then moving a foot farther out and pulling that into the first cut and so on up the board, you will always be starting with cutter newly aligned to the board. Should you stray, it’ll be for only a small bit and it will end where the previous cut started, hopefully correctly aligned.
Molding planes similarly should start at the end of the cut and work backwards. You will always be reregistering the fence on the wood and getting a consistent cut and angle.
It is the perfect word. IN-PAINT: PAINT IN-side the limits of the repair. Often professionals and amateurs alike try to "blend in" the repairs to the surrounding surfaces, increasing the size of the repair area. However, it is better to match the repair to the surrounding surface using pigment and dye, being careful not to go over into undamaged areas. Since perfect color matching is impossible because pigment and stain do not reflect light the same as wood and do not reflect the same using different light sources, we can only approximate the color and sheen that aged wood and aged finishes have acquired over time using dyes and pigments. It is better to keep our repair area as small as possible so our less than perfect color match is at least as small as it can be.
This concept can be expanded to include limiting sanding to the repair area only. Sanding around the repair until the surface patina has be sanded off, will make the wood go back to its un-oxidized color. For light woods like maple or cherry that have darkened, the sanded area will become lighter. Dark woods like mahogany and rosewood, especially rosewood, which will have acquired a beautiful orange patina, will darken considerably. All could be avoided if the repair is surfaced only within the repair area. Sandpaper may not be the optimal tool. Small scrapers might offer better control.
While replacement of lost material is common, by keeping the repair and subsequent color match confined, the repair will be less noticeable and, even better, less original material is lost.
The bandsaw maybe the most under-appreciated tool in the modern cabinetmaker's shop. Worse yet, the tablesaw, the staple of those shops, have made their way into the average hobbyist's shop. Tablesaws excel at cutting sheet goods and wood under 2" in thickness. Great for making kitchen cabinets. They also excel at cutting fingers!* When a tablesaw is your only power saw in the shop, there is a temptation to use it for cutting small bits of wood. This is dangerous as the work can bind, get jammed, and get thrown. Personally, I have found a tendency to try control the work (wood) when the saw misbehaves and that is often to inadvertently put your hands closer to the blade. Not good!
The restorer and, I would think, the hobbyist woodworker, is less concerned with plywood and uses the bandsaw to rip and crosscut wood safely up to the capacity of the saw. My 14" Walker-Turner can resaw 6 ½" and make 1/16" inlay. It will saw ebony and pine with equal efficiency. And you can safely cut small bits of wood using a zero clearance plate. When the blade breaks, most of the blade stops and a small part of the blade collapses inside the saw. Better yet, my reaction has been to be startled and move my hands away from the blade! The new blades have wonderful welds and breaking a blade is almost a thing of the past.
As with any machine, it should be adjusted properly with a sharp blade. Most of the frustration I have found is with a machine using a dull blade and/or not having good tracking. In my restoration studio, this machine does most of the sawing in the shop, with my Japanese ryobas and dozukis doing the rest.
*Thank goodness for SawStop, a tablesaw that retracts the blade when it makes contact with a conductive surface, human skin!