I can't believe that it's over 2 months since I started work on this kickstart shaft, but I guess plenty of other things have been going on at the same time including railway stuff, making the parts to exchange for the 3D printed gears and other things. However, we are well on the way and this latest post is about milling in the vertical slide set up for the kickstart shaft shaft stops and the platform for the kickstart pawl.
Milling the end stop took two attempts to get the angle right but I'm very satisfied with where this is now:
This is the other end which is a bit more difficult because it's a completely enclosed corner. I started this with a 3/8" end mill and finished with a 1/4" slot drill to remove as much material as I could. It may yet need to clean up with the Dremel.
The next step is to rotate the shaft and start with the flat area where the pawl sits. I've marked the edges of the area using the original shaft as a guide and I've tried to set up the new shaft in the vice such that the virtual area defined by these lines is in a vertical plane. I used a pointer in the collet to line up the marks as shown below - this is a later picture, but it gives you an idea:
Cutting at around 0.5 mm per pass, we start to define the flat area:
Many passes later and we are nearly there. The finish is fine, despite the grumbling vibration from the lathe. I tightened up the gib strips during this operation, but I really must look at the saddle retaining strips.
Soon afterwards, we are done. The platform for the pawl is 10 thou narrower than the original.
Next step is the holes for the pawl and the pawl spring.
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