In order to get the kumiko pieces to the required dimensions, I needed a way to use the hand plane without destroying the pieces in the process and a thickness planing jig was the answer. Using some diagrams from FW #204 I put together a fairly simple jig.
Basically it consists of 2 “L” shaped strips glued and brad nailed to a board at the width of the plane I intended to use. In this case a #4 bevel up smoother.
I inserted a piece of 3/4 plywood sized to the same width as the smoothing plane to ensure that the two “L” pieces remained parallel. For the wood I used QS Sycamore.
The fit with the smoothing plane was a tad tight, but a little work with the paring chisel took care of things.
In theory, a spacer is used to bring the kumiko up to the desired height where the plane then shaves off the difference. One could then use different spacers with varying thickness to effect the desired height of the piece to be planed. In reality, I ended up using the low angle block plane which conveniently fits into the lower level, had little to no room to shift side to side and beautifully shaved off the thickness necessary to get the kumiko to spec.
While I didn’t end up using the jig for the initial intended purpose, it worked just fine. And I’ll still be able to use it with the #4 when the time arises.