9 Attachment(s)
Wood worm wheel whittled!!
Machined a hollow locating sleeve:
Attachment 399918
12mm thru for threaded rod, 19mm to locate in the dividing plate, 16 in the gear blank.
Set the plate tilt at about 3°, and fine tuned it against the worm with a square (V block):
Attachment 399919Attachment 399920
Instead of edge finding and/or indicating, used a square against the plate to draw the centreline:
Attachment 399921
which I will line up with the middle of the cutter for plunging:
Attachment 399922
Then, rotate 20°, plunge, rotate 20, et c.:
Attachment 399923
I went around again, and made the cut a little deeper, so that the involute side just started to relieve the middle of the gear cylinder.
End result:
Attachment 399924Attachment 399925
Not the best mesh. About half way down. Looking at the worm, it is lathe cut (judder marks), and non-symmetrical (different angles on the two sides), and has some burrs on the top land.
Slightly wider spacing between the teeth seems like it would mesh better. I could do a slightly larger diameter (e.g. 53mm instead of 50mm)? Or I could try to cut the worm wheel deeper, which might get closer to the 30°? Or I might also try to improve the shape of the worm.
But, for now, I'm happy-ish with the worm wheel profile. So, trip to Edcon, $81 chunk of Brass from the offcuts bin, and into the lathe to make a real gear blank:
Attachment 399926