With the space for the pawl milled out, the next step is to drill some holes for the pawl spring and the pivot pin. When that is done we can function test part of the mechanism.
To drill for the pawl spring we keep the vertical slide setup in the lathe. Getting the height is straightforward because we can use the old shaft to line the vice up with the drill and thus ensure the angle of the hole is correct.
Since this is going to be drilled in a surface that isn't perpendicular to the drill, I start the hole with a 1/4" slot drill and cut for a few millimetres, finishing the hole to depth with a twist drill.
The twist drill is marked to depth with a bit of tape. A 1/4" drill isn't quite enough - I drill it 6.5 mm to clear the spring and it's plunger:
The holes for the pivot pin aren't quite so easy. I'm going to make a small deviation from the original design here - The original pin is stepped, it's a 5/16" pin reduced to 9/32" for part of its length. Strangely the larger size is inboard, so the step prevents it moving outboard. I want to make the smaller size inboard so that there is no possibility of the pin coming loose and interfering with the layshaft first gear.
The problem with this approach is that there is no way a conventional twist drill can reach.
I ordered some long series twist drills from the excellent Tracy Tools. They will be here in a few days.
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