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Make Your Own Drawbore Pins in One Hour Proper drawbore pins are absolutely
the key to successfully and consistently executing a drawbored
joint. The pins allow you to work with bigger offsets, to know
exactly how the joint will fit before final assembly and to pave
the way for your peg by slightly distorting the hole through the
tenon. You can purchase traditional pins from dealers of antique English tools, though you will spend $45 to $80 for a pair, and you must sometimes search for the smaller-sized drawbore pins. I’ve had good experiences with two dealers: Tony Murland’s Antique Tools (www.antiquetools.co.uk) and Classic Tools (classictools.com). Both are British dealers that sell to the United States. The other option is to make your own. It’s easy and takes only about an hour once you have the materials in hand. The metal part of the tool is easy to find. Machinists, bridge builders, mechanics and anyone who works with metal has a set of tools they use that are much like drawbore pins. They’re sometimes called drift pins, alignment tools or line-up tools. And they come in a wide variety of sizes and tapers. To make your first set, I recommend you buy a set of alignment tools from Sears (www.sears.com, 800-349-4358 or visit your local store). The company sells an eight-piece set of punches and alignment tools under its “Companion” brand name. The set, which contains two alignment tools for our purposes, costs $6. The model number of the set is #30130. One of the alignment tools in the set has a 5⁄32 " tip that tapers to almost 3⁄8 " over a span of almost 4". This is a decent tool for furniture-scale work, though it will be much easier to navigate the offset if you grind the tip a bit smaller. The other alignment tool has a 3⁄16" tip that tapers up to a bit shy of 1⁄2" over a span of 4 5⁄16". This is a good size for larger work. The first thing to do is to sand the black paint off the tapered section of the tool, which will come off on the wood eventually. Then you need to set the alignment tool into a wooden handle. Drawbore pins must be twisted in and out of their holes to work properly in my opinion. (Striking them is not a good idea.) I prefer a traditional tapered octagonal handle, which is easy to twist in and out of the holes. However, a lathe-turned handle will work nearly as well. First bore a hole straight into the end grain of a 1 1⁄4" x 1 1⁄4" x 6 3⁄4 " scrap of wood that will accommodate the hex-shaped end of the tool. For the smaller tool, use a 13⁄32" bit for the hole (this is why you bought that fancy set with so many bits!). For the larger tool, bore a 17⁄32 " hole. If your bit isn’t long enough to go deep enough, finish up the hole with a long auger bit that is a bit undersized (3⁄8 " or 1⁄2 "). With the holes bored, shape the handle to your liking. I tapered my handles to 7⁄8" or 1" square at the small end. Now comes the fun part. Get a propane torch and heat up the hex shank of the tool for a minute or two. Then knock the handle onto the tool. The heat will char the wood as you insert the steel and prevent the handle from splitting as its driven on. Allow everything to cool down and then add a couple coats of wiping varnish to your handle. Now you are ready to explore this ancient joinery technique for yourself.
Christopher Schwarz, Editor - Popular Woodworking
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