I made some rack and pinion reduction drives for my new project.

6061 aluminum with 120/19 Gates GT2 3mm belts and pulleys.  Final ratio is 6.32, and after the 20 tooth rack gear I'll have about .50 IPT.

It's a Nema 23 setup.

Very nice work Michael.
How are you getting the tension on the drive belt ?

Tweakie.

Thanks

Well.....the first design had an idler that also put more wrap on the small pulley.  It turned out to be unnecessary and just added a lot of drag.  The belt maintains 7 teeth engaged without the idler, and is adjusted by slotted mounting of the stepper.

Nice craftsmanship!