Struggling a bit with the 9 tooth pinion gear cutting.
I have only a Mod 2 12-13 T gear cutter.
My problem being as i move the cutter into the blank pinion, the teeth wall between the teeth decreases, in fact they are looking like a wedge
and will not mesh with the scroll gear teeth. see photo of the parts marked 2 3?
The reason I think is even though I have twisted the indexer to 20 deg. (40 degrees inclusive angle) as the cutter?
moves in then the cutting diameter changes, the cutter dia is a standard 58 mm, the teeth are only 12 mm long.
I think the the original pinion teeth of a chuck bought from a tool supplier see photo marked 1 were hobbed, or a special smaller dia gear cutter was used.
There may be several ways around my problem, (a) to make a fly cutter tip with the involute form, thus greatly reducing the cutter circumference,
the other option is (b) to CNC cut, When the X axis moves along the 12 mm then the? Y axis? will move out 4.386 mm, keeping the point of contact of the cutter circumference constant. I have also machined on the lathe new pinion blanks, making them longer as the other current problem being the cutter hits the collet locking ring even though I am hanging the blanks out of the collet as far as I dare. Once finished with the gear cutting, the blanks will be parted off to length and a square milled in for the chuck key.
Photo shows marked 4, a double ended pinion blank, extra long for the collet holder to avoid the cutter hitting the serrated ring.
marked as 2 , a aluminium proto before I attack LOL the phosphor bronze, already scrapped one piece, it was to short anyway.
Any advise on how to get around this, then always welcome.
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John
John Lindo