Anyone can restore a saw handle — it's not rocket science. It does require some patience, but most of all a determination to see it through. There are a lot of pics on this page, and it can seem a bit overwhelming. But trust me on this—it's easier than you think. This is my method, and like anything else, other methods will work. Have fun with it—the worse that can happen is you simply saw off your repair piece, and start over.
Here we have a nice old Harvey Peace panel saw handle with a blunted upper horn—a pretty typical scenario. This shot reflects a suggested outlay of the equipment and finishing supplies I like to use. Essentially, you'll want a small crosscut saw, your dovetail saw, rasps to contour-shape the horn, some cyanoacrylate glue, a dremel with associated buffs and sanding drums, a scraper, an exacto knife, clamps, and even rubber bands.
...that's what the SF medics used to tell me anyway before scrubbing an infected owie away with a ScotchBrite pad (in the name of debreeding the wound, right?) As it applies to horn repair, what you're doing is cutting away the damage. Clamp the handle in a vise and cut away the damaged part of the horn with a small tenon saw, no coarser than 14 ppi. You may have to cut away the entire damaged piece with a vertical miter cut, amputating the damage completely, such that the underside of the horn cutaway is longer than the upper side. This utilizes as much of the remaining wood on top as much as possible where the repair will be most apparent. Other times, the damage won't exist across the full depth of the horn, like the Harvey Peace handle I'm working on here. What I'm doing is creating a notch—a 90-degree angle for the repair piece to fit into. I make a cut across the grain with my crosscut saw, and make the notch with my dovetail (or small tenon) saw, by sawing with the grain to the crosscut kerf. Do this whenever possible, because two glue-up surface are stronger than one.
Once you've made the cut or cuts to remove the damaged wood, you'll now want to pare it smooth with a chisel (for notched cuts), or a block plane (if making a through cut. Notched cuts require a 90-degree angle, and so some tweaking here is in order prior to gluing up the repair wood.
Now rip-cut your repair piece of wood lengthwise to appropriate height with a shallow mitre appropriate to the grain flow of the handle. Much of the time, you'll want to use apple, but cherry is a good choice too. You'll wind up staining it to the look of the handle later on anyway. The main thing is to predicate your cut(s) to match the grain flow on the handle. You don't want to glue on a piece of wood with grain that zig-zags from the original wood.
Here's a shill for my Bad Axe Bench Hook set. This is a very useful accessory while you’re making these cuts. Lee Valley’s wonder dog, bench pup, and bench clamp are other great accessories to free up your hands while you work.
Test-fit the repair piece to the handle. Don't worry about cutting it to length yet—it's easier to clamp with a longer piece of wood. Also, make sure the repair piece is about a 1/16" taller and wider than the handle wood, so that you can shape the contour, height and width to size in the pics that follow. Again—you're miter-cutting the replacement wood to match the grain direction of the handle. Don't attempt to shape or cut the repair wood yet. Use an over-sized chunk. The repair piece should be thicker and longer than what is required. You’ll cut and shape it to size later.
Here's the fun part: use a couple of rubber bands to clamp the repair piece into position. Rubber bands let you clamp the repair piece into position flush with the notch or miter cut, and they work great for clamping asymmetrical pieces together. Don't glue it up yet, so you can get the pieces lined up correctly. Note the piece of bracing wood to achieve the direction of pull I want.
Now clamp your handle in a vise, gently lift the repair piece, and apply the glue, making sure you get both surfaces. I like using the gap-filler cyanoacrylate glues available from Lee Valley. Wear gloves and like Mr. Bill, don’t inhale—this stuff is potent. Wipe off excess glue with a paper towel, and clamp the handle in an orientation where any gaps to fill will pool the glue in place for a stronger seam. Let dry overnight.
If you're feeling cocky by now, you can also attempt to repair other damage, like the through-crack I'm gluing up just above the lower horn. In this shot, I'm wedging open the crack with a screwdriver, while applying the glue. It's smarter to wait until the other repair is dry first, but I was feeling pretty full of myself the day I worked on this handle. Wedge apart the crack with a thin-bladed screwdriver or an exacto knife, and shoot the glue into the crack using a wood glue syringe. If you don’t have a syringe, use a razor blade or the tip of a knife to 'push' the bead of glue into the crack, and gravity will take its course. Use two clamps to squeeze the crack closed along the vertical and horizontal planes. If you have a major crack in the handle, I’ve found it useful to insert two opposing and tapered pieces of wood inside the grip to spread the crack. If you wind up completely breaking the handle, don’t flip out. Just glue the pieces together and clamp.
The next couple of shots show how I clean up the medallion sawbolt and sawnuts using a brass wire wheel on my Dremel. This is a matter of personal taste. Some people like shiny, others don't. When working on a vintage saw, I clean out the gunk with the Dremel without overdoing it, leaving some patina to match the appearance of the saw handle itself. In situations where I have to completely strip the handle, I'll make the brass shiny at that point. Regardless, exercise care not to grind down the embossed artwork and lettering within the medallion.
Dental tools aren't just for probing root canals and cleaning your M16; they work great to pick out decades of gunked-up skin cells and oil inside slotted sawnuts. I've often found that if you clean out the slot, you'll be less apt to distort the brass when removing or tightening the fasteners with your screwdriver. On that note, file or grind the flathead screwdriver you use to achieve a thinner tip so it can fit all the way inside the sawnut slot—antique sawnuts often require a thin blade to fit.
Here's where purists will take umbrage with me—actually polishing the medallion sawbolt/nut. If you like shiny, you can chuck the medallion sawnut in your cordless drill and bring the polishing cloth to the spinning medallion. If you want to retain a clean patina appropriate to the salvageability of the original finish, a gentle buffing will suffice, such as I'm doing here.