Lost Art Press

To make the conical mortise for a piece of staked furniture, I first bore a hole that is the smallest size of the overall joint – typically 5/8” in diameter. Then I follow that up with a tapered reamer that turns the cylindrical mortise into a cone-shaped mortise.

There are lots of good ways to do this. Here is the method that suits my tools, head and hands.

I make the 5/8”-diameter mortise with a brace. You can do this with a drill press with an angled table or any other boring tool. But after trying many methods during the last 11 years I have settled on making the initial hole with a brace and an auger.

I sight the drilling angle against a bevel gauge that I tape or clamp to the underside of the seat. As long as I sight against only one angle (what we call the resultant angle), then I can get within a fraction of a degree with this method.

Like with all good augering, I reach below the seat to feel for when the auger’s lead screw pokes through on the exit side of my hole. When I can feel the lead screw, I flip the seat over and finish the mortise from that side.

That’s the easy part for me. For many years I struggled with reaming. When I used a brace I tended to create an elliptical mortise, which is no good. After much practice, I still made a wonky mortise. I know other people do this operation with ease, but it’s out of my hands, apparently.

Then I tried reaming with a cordless drill that was set to a low speed and maximum torque. For some reason, this fixed my mortises. Instantly. Perhaps I’m suited to focusing on the direction of the cut while the drill supplied the round-and-round.

I’m not saying this is the best way, but it’s something to try if you have the same problem.

— Christopher Schwarz

 

First-time chairmakers often confuse the terms “rake” and “splay” – and never mind the other names for the other angles in a chair.

After I took my first chairmaking class 11 years ago, I made up this little explanation for myself so I wouldn’t forget.

Chairs are like saws.

When you look at a saw from the side, you can see the teeth raking forward or backward (depending on the filing). When you look at a chair from the side, you are seeing the rake of the legs. And chair legs can rake forward or back – just like sawteeth.

When you look a saw from the front, you can see the teeth bent out from the sawplate. This is called the set. When you look at a chair from the front, you can see the legs splay out (they never splay inward that I know of). “Set” and “splay” both begin with “s.”

OK, it’s not the most perfect explanation, but it has prevented me from mixing up the terms for many years now.

— Christopher Schwarz

The nice thing about geometry (aside from sitting next to Cris Titsworth) is that you can perform some operations that look difficult with surprising ease.

For example, let’s look at my “wireframe” model for my next project. With needlenose pliers I can adjust the rake and splay of the legs, which are made from 12-gauge wire, until I’m pleased with how the legs look from all directions.

Then, using some formulas picked up from old books (see above, I can’t believe I am showing you this)…. I can dial in my angles.

Then it’s a cinch to knock out the finished piece:

Of course, I can adjust the legs to produce these simple variants.

Or, by simply changing the value of X, produce this:

— Christopher Schwarz

Perhaps this is because my shop is small, but I don’t like building full-size mockups of projects during the design process. When I’ve built full-size models in the past, I felt bad about wasting materials. Cheap pine could actually be used in a piece of furniture, and pink insulation could be protecting Hello Kitty from the cold.

But building half-size models is OK for some reason in my head. I can cut most parts from scraps in my waste bin. I use wire (clothes hangers) and cardboard (waste from boxes) at times. And the components are large enough to make it easy for me to imagine how the piece would look.

Today I finished up a half-scale model of a staked-leg backstool I’m working on for my “Furniture of Necessity” book. After dialing in the rake and splay of the legs, I concluded that this piece of furniture was so unique that it should bear my name – the Christopher Schwarz (TM) Staked Backstool.

No one has come up with a Backstool like this one with these particular angles, and so I, Christopher Schwarz, would like to share it with you so you can feel the full-on Schwarz when it comes to Schwarz Rake, Schwarz Splay, Schwarz Sightlines and Schwarz Resultant Angles.

To lay this out, you’ll need to use a special technique that I have developed after more than 35 years of examining angles as they result to other angles, plus segments, vertices and Cris Titsworth, who sat next to me in high school geometry.

That technique involves setting the angle of a leg and determining its position in relation to line that is struck off the perpendicular axis of the spheres of influence that are tangent to the Titsworth Twins, who were nice and would play Lifesaver games on the band bus but were not as hot as their older sister, Cris.

You can sight this angle using an ordinary try square, laid flat on the bench and sighted so the leg looks 90°. Then you set your bevel gauge to an angle that appears in line with the leg and try square.

This three-legged Christopher Schwarz (TM) chair is fondly dedicated to Joe Kent Wagg. Thanks to its three legs, Joe would be unable to tip backward in the chair when Ms. Widemann would duct tape him to the chair.

And scene.

— Christopher Schwarz