RIFF/ETUDE: Making the Action Adjustment Tool

KEN: I devised a way to make the necks of my guitars adjust in height relative to the body, and thereby change the action of the guitar, relieving the bridge of this unwanted job.

This design has proven itself beautifully over the last 15 years, and I’m very happy with it.

The neck is moved up or down by a clever little fastener known as a clamp screw or wedge screw. Had it been I that named it, I would have called it a turnbuckle screw.

It has no head, so it looks like a set screw, but each end is threaded differently, one end left hand, and one end right hand. When turned, it either draws things together, or pushes them apart.

This fastener is simple, and perfect for this job. It’s adjusted by an 1/8” hex wrench, inserted through a hole in the back of the instrument.

I made my own wrench, sporting a wooden “butterbean” button to be more attractive than the utility versions. This first design was dirt simple, just an oval piece of wood with a cross drilled hole to house a short length of hex steel. Most of these survive, but some cracked and failed.

I decided I needed Rev 2.

I ordered some ebony Viola tuning pegs, scratched my head, and had some fun on the lathe converting them to Rev 2 adjustment tools that I consider to be unbreakable in normal use.