The pinion gear for the saddle traverse on my Myford S7 is very worn, and faced with a =A350 plus postage cost from Myford, I'm tempted to cut a new one myself (12 teeth, 20 DP, 20 degree PA). I have a suitable hob.
The gear meshes with a steel rack, and I would be very grateful for advice on the best material from which to make it. For example, would a bronze or cast iron gear be better than a steel one in this application?
Mike
Mild steel or bronze, drawn bronze that is, not cast, will make a decent pinion. Cast over 12 teeth will be too weak given that they are 14.5 degree PA and not 20 degrees. The originals are MS and there are many 1,000's out there
-- Regards,
John Stevenson Nottingham, England.
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Thanks John. Really useful. I'll go with MS.
Are you sure about the 14.5 degree pressure angle? I measured the angle on the rack as carefully as I could, and it looked closer to 20 degrees. Maybe mine is worn more than I thought!
Regards
Mike
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