small timing belt gears

[rungemach]

I'm in the process of building a 3d printer (Reprap) that uses small T5 drive belts to move the axes.
The laser cut wood gears in the kit did not fit well and the Shark was called into play to cut some new ones.
This size is not available commercially, (as 10 tooth is the smallest common pinion for T5 size that I could find in metal.)
The firmware of the Reprap needs 8 tooth for the travel to come out right with the belt driven axis.
Inner hole must be a press fit onto the stepper motor shaft. Shown with the belt to illustrate fit, and a dime to illustrate size.
The belt was held in place for the picture with 2 small needles.

Cut with .0625 end mill in 1/4" birch ply, Bosch colt with precisebits collet.
Workflow was Autocad to Vectric to Mach3 running the Xylotec driver board in 8th step mode.

[Turbo1zz]

Wow! Now that's one small gear. I've been playing around with cutting small gears and have used 1/8, 3/32 and 5/64 end mills to cut small gears out of 1/4 inch ply but have yet to find a .0625 end mill that has a cutter length more than 3/16". might I inquire where you found your bit at? I will be purchasing the Precise Bits collet for my DeWalt router since I'm noticing a good amount of runout from the standard collet. The gear in the picture i've attached is .64 inch across and was cut with a .0781 end mill.

Thanks for sharing the gear and look forward to seeing the 3D printer when it's all done and cranking out parts.

[rungemach]

I used a Megatool "chip saver" bit for this as I have some of them here already.

I believe that Precisebits has a 1/8 shank .0625 deep reach fishtale end mill bit that has a .5 depth,
I have some on order to try but they have not arrived yet.
I don't usually go below standard 1/8" dia, but I have Megatool bits down to .35 mm (.0138 in). (very fragile)
The gear in the picture is .475 outer diameter. I could get away using the .0625 bit as the valley profile is not critical for the belt drive.
The valley is a bit more rounded than it should be, as I cut it a hair deeper to compensate.
The Reprap is the "Mondo" large version from Techzone. It's proving to be an interesting project.

The Megatool bits can be found on ebay from time to time.
and at places like http://www.timberlywoodturning.co.nz/pr ... ling-.html

You will love your Precisebits collet setup., their 1/8" setup is very impressive. A must -have IMHO.

Bob