Today I was pleased to make the last few cuts on the main 1 1/8" diameter part of the kickstart shaft. With carbide tooling, the right geometry and the right speeds and feeds the finish comes up very well and the fit is spot on.
The next job is to mark out and cut the 3/4" diameter for the kickstart lever:
I cut that in about 8 passes and followed it up with my form tool to generate the gentle radius on the end:
Unfortunately the inside diameter of the kickstart shaft is not round - I guess this is to be expected as it has been fitted with a cotter which pulls over to one side and has probably distorted the eye. I may have to obtain a 3/4" expanding reamer to sort this out - you can get cheap ones for about £15.
I'll probably leave ordering that until I've started milling and have worked out what other cutters I might need to buy.
Fitting the kickstart shaft from the right side of the gearbox and cover reveals that it fits nicely:
I didn't expect this snag though. What we looking at is the stop that limits movement of the shaft - the bit I didn't expect was that these stops are riveted in place and cannot be removed, which means I can't check the length of the 1 1/8" section until I've milled the slot that this stop fits in.
Some measuring suggests that the length is acceptable - maybe even a little long, but only a couple of millimetres at the most.
So the next step is to start thinking about the milling side of the work and to do this we need to have a flange machined into the waste in order to retain the shaft on the rotary table:
Second thing we need here is a 5 mm hole in the end, where the revolving centre is at the moment, to locate the shaft centrally on the rotary table. We will probably have to make some special washers to hold the flange to the table but more of that later.
So that was a good day of progress.
And the milestone? O yes! This week the blog has passed a million hits!
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