DIY Thumb Plane

I need a couple of small planes for finishing soundboards. These are expensive so I figured that the best thing to do was make my own.

The blade is a strip of gauge plate or ground flat stock – O1 carbon steel in unhardened form, readily available from EBay. I’ve had this bit lying around for years left over from something else. Being unhardened it is easy to shape with hacksaw and file.

I didn’t measure anything on this other than the angle of the bed of the blade (45º). The pictures should show how it all goes together.

The wood is oak from an old chair leg, cut on the bandsaw and sanded to a good finish.

Bits of wood
Gluing together
Finished plane

The blade is locked in place with a mahogany wedge left over from making a ukulele neck scarf. The angle is a bit big – it would be better a few degrees less – but with some tweaking it works well.

The blade was hardened by heating red hot and then plunging into water. Oil would be better for this type of steel but water is cheaper and doesn’t catch fire. I tempered the blade to a light straw colour. It seems to hold a good edge.

The plane works well. The great advantage of making it yourself is that you can shape the thing to exactly the right shape for you. Plus it didn’t cost much and was fun to do.

Next job is make a smaller one – 10mm wide blade. I’m just waiting for the steel to arrive from EBay.

Update 29 March 2023: Two more planes

10mm planes – one flat, one convex

These have blades made from 10mm x 2mm gauge plate. Both work very well. BTW these are simple to adjust:

  • Hit the front to increase the depth slightly
  • Hit the back to reduce the depth or release the blade

They are actually easier to adjust than many metal bodied planes with adjusters.

1 thought on “DIY Thumb Plane

  1. Pingback: Archtop Pineapple Ukulele Part 2 | Martin's Blog

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