On 16 Jul 2003 16:03:21 -0700, (Claude P) wrote:

Hi guys, could anyone tell me what would be the best way to cut a 5
teeth sprocket for a 3/8 pitch chain.
Thank you in advance.

I made a six tooth for my snowblower, this small a sprocket will only
work at very low speed. Anyway, here was my steps.

1. measure diameter of roller. Use a drill 1/64 over this size to
drill the base of all the sprocket teeth.

2. Do a layout of holes around a circle with the distance between
holes the chain distance. In your case, you're drawing a pentagon, 5
holes on a circle with the distance between holes 3/8 of an inch. You
need to find the diameter of the circle that solves this. In my case,
I used autocad.

3. Using a rotary table, drill the center hole and sprocket holes in
your disk.

4. I faked in the tooth ends with a bandsaw and finished with a die
grinder. If you're into perfection, the sprocket side is defined by an
arc centered at the center of your drill hole with a radius equal to
the distance from the center of one roller to the inside edge of the
next roller.


Hope this helps.

I now have access to master cam. It will draw up the sprocket in just
seconds. Then run it on a CNC mill. My son has made several perfect
sprockets this way for his four wheeler.



Karl