The Black Knife

In 19th-century English workshops you could be sacked (fired) for wearing eyeglasses. There are even accounts of how a shop might have a certain phrase that was spoken when the master was about to walk through the workroom. When that phrase was uttered, all the eyeglasses would go into hiding.

I would have been fired in first grade. My eyesight is so poor that teachers worried I was mentally deficient. They didn’t figure out that I was almost blind until I got my hand stuck in a giant metal door that I couldn’t see coming... .

All this is to say that I need all the help I can get when I’m in the shop and trying to follow my layout lines. Using a marking knife is a huge help because it provides a physical point for me to register a tool.

But when you deal with coarse woods such as oak, a knife line might not be enough. In fact, a knife line can look just like a grain line at times. So I use a two-part strategy: I knife in my lines, then color them with a mechanical pencil.

But not just any mechanical pencil.

When microns count, I use an Alvin Draft/Matic No. DM03 mechanical pencil with 0.3mm lead. The lead of this pencil is fine enough to drop into the bottom of a knife line and just darken the floor of the knife line.

At left, 0.5mm lead in a knife line. At right, 0.3mm.

Mechanical pencils with thicker leads, such as 0.5mm and 0.7mm, tend to darken the two lips at the top of your knife line. That can actually be handy at times because you can easily split the knife line by sawing, paring or planing away one of the two pencil lines.

The downside to these thicker pencil leads is that they tend to wander, especially when marking coarse woods. Because they mostly ride on top of the wood, they love to hop into a grain line and take a detour.

The 0.3mm lead stays in your knife line and tracks it like crazy. It’s like having a knife that leaves a black knife line in its wake.

Now the 0.3mm pencil is a royal pain. The lead is fragile, so you have to learn to use a light touch when marking your lines. Plus you can’t extend the lead out very far or it will snap. Oh, and because there’s not a lot of lead in 0.3mm, the lead gets used up quickly.

But dang oh dang does it help me see my lines. So for me, it’s worth it.

I bought mine at an artist supply store. If you get one, be sure to get some extra lead while you are there.

And now back to more endless dovetailing on this campaign chest. One assembly down; five to go.

— Christopher Schwarz

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