Anyone know of a source for GT3 pulleys that has competitive pricing? I'm looking for an 8:1 gear ratio with the large pulley around 6" diameter (if possible). Large pulley for a 1" shaft and the smaller pulley would need to fit a 5/8" shaft. Nylon or aluminum would work fine for the larger pulley. Hoping I won't need anything custom made. Thanks!
B and B Manufacturing SDP/SI Both will also custom manufacturer. B&B has a 120 tooth GT3 pulley but it is no where near the shaft diameters you are looking for. And to put a 16 tooth at the opposite end to get anywhere close to your ratio, leads to a pulley with a total outside diameter of only 5/8". What you are wanting to do is going to require a much larger tooth pitch and may also require a better look at what is actually possible. A 3/8 pitch belt which will work with a 15 tooth, 1.7" diameter pulley on a 1/2" hub at the smaller end, requires a 120 tooth pulley at the other end. A 120 tooth pulley is over 14" in diameter.
For clearance I would like to get by with a 6" pulley on the large end. I may have to try a Poly-v belt as they can handle a small diameter pulley on the motor shaft. Would have to go all the way down to 3/4" on the motor shaft to get the 8:1 gear ratio. They do something similar on a clothes dryer using an idler pulley to keep contact with the small motor pulley on roughly half the circumference. I don't need the teeth for timing so it may work. Thanks for the suggestions!
