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That would work Marv, even a non carbide slitting saw would do, it would just take repeated cuts until the width was achieved, and a little more clean up at the end. The 2 1/2 diameter doesn't appear to be critical so even a 2" saw or 3" one should work if available...the wider the better of course.
One other thing we are lacking is a boring tool for the mill!Aside from not looking as pretty, would this feature function as well with a flat bottom instead of a radius?
Quote from: Heffalump on February 25, 2014, 03:19:57 PMOne other thing we are lacking is a boring tool for the mill!Aside from not looking as pretty, would this feature function as well with a flat bottom instead of a radius?I used a flat bottom, then angled the piece and cut a ramp. It doesn't look too bad that way.Alan
Hi JimThe two countersink screws should be drilled for clearance for #4-40, and the hole showing between them should be drilled and tapped for #6-32 thread.Don't drill the hole between them through into the groove either - it should be a blind hole. Basically, looking at the base, all the blind holes from the top must be threaded for #3-48, the three blind holes from the bottom must be threaded #6-32, and all the through-holes should be drilled at clearance size for #4-40.M3 metric screws are a great replacement for the #4-40 American threads on most parts of Elmer's engines. If you do use different fasteners than the American ones specified, make a note on your plans to that effect next to mating parts - so that you can keep track of which holes must be what sizes.Kind regards, Arnold
Yes it is the crank pin. I would look to go up to 5mm rather than down to 4mm. If you are worried about the amount of metal left either side of the pin you could reduce the diameter of the curve on the top and bottom (hand file rather than turn).Jo