01-06-2021, 10:02 AM
Thanks Willie,
The cutter is simply a rack in circular form, then gash the teeth and back clearance in the mill.
I went with 14 1/2 degree pressure angle as thats acme thread and could use my acme threading fish to check the lathe cutter and align it. Tooth spacing on the cutter is the same as a rack gear would be, got the formula from the machinist hand book.
Took two tries, I made the first cutter with too wide a tip on the lathe tool. When cutting the gear I was toping the teeth before I could get the measurement over pins right to get the pitch dia I needed.
Used O1 then hardened but didn't both annealing it, seams to be lasting well.
The cutter is simply a rack in circular form, then gash the teeth and back clearance in the mill.
I went with 14 1/2 degree pressure angle as thats acme thread and could use my acme threading fish to check the lathe cutter and align it. Tooth spacing on the cutter is the same as a rack gear would be, got the formula from the machinist hand book.
Took two tries, I made the first cutter with too wide a tip on the lathe tool. When cutting the gear I was toping the teeth before I could get the measurement over pins right to get the pitch dia I needed.
Used O1 then hardened but didn't both annealing it, seams to be lasting well.
Free advice is worth exactly what you payed for it.
Greg
Greg