Definitely not Boring: Old Tech Drills Any-Shaped Hole

When recently ogling some antique pocket knives at a local flea market, I noticed the inlaid shield in the handle. I remember thinking, “Given how many of these things were made, there’s no way they carved each one of these inlays by hand.” As it turns out, I was right! Before the CNC milling machine, before the electric rotary tool, and before the router, there was the parser drill.

Capable of drilling a hole in just about any shape (including ones with sharp corners), the parser drill is a perfect example of the quirky ingenuity of craftspeople from the past. It consists of four main pieces: the iron template, the parser, the breastplate, and the bow. While it sounds like a complicated setup, the tool allowed a variety of shapes to be routed out of wood, bone, or ivory with precise repeatability.

To use the parser, the leather strap of the bow is twisted around the wooden bobbin and the point on the back of the parser is inserted into the breastplate (which is fastened around the user’s midriff). Then the template is clamped to the material, and the cutting bits of the parser’s legs are inserted into the template. By leaning against the parser and moving the bow back and forth, the bits would spin around inside the template and cut into the material. Since the tip of the parser is split, the cutting bits spring against the inside edges of the template, carving the exact shape into the material.

Unfortunately, it seems that this tool has mostly passed out of use and is now more likely to be found in a museum than a workshop. Even if you did want one, it’s pretty unlikely that you’d even be able to find one for sale. Like many antique tools, though, it’s simple enough that you could make your own!

Thanks to jewelry-maker Peter McBride, the parser may have another life yet. On his website, he describes how he made his own parser drill from an old industrial hacksaw blade, and even shares his successes (and failures!) in using it. He also goes a step further and shares a method for punching the shapes to be inlayed out of metal, rather than cutting each one individually. With these methods for rapidly making both the metal inlay and the routed hole, you can imagine how the craftspeople of the past turned out consistent and beautiful work without a CNC machine or even a single powered tool.

If you’re doing your own research on parser drills, you should know that it also may be called a passer drill, two-legged parser, shielding parser, or a bifurcated bit drill. Probably ,the first place to start your research would be the WKFineTools article about the Forgotten Art of the Two-Legged Parser. The legendary Roy Underhill also used a parser drill in one episode of The Woodwright’s Shop.