Aquiring an Andymark GEM500 gearbox.

Looking for a total of 4 stages of a GEM planetary gearbox + the output shaft assembly for a standard 2.5" CIM. mathematically this will give us enough grunt to get the robot off the ground and then a little mercy room to keep the CIM from burning out. but then again “mathematically” two andymark AM-2193 with the 188 gearbox would lift it, but we tested it with 80lbs, no good. hopefully can get some input on other choices

but the main problem we have is in order to USE a GEM500 4 stage gearbox, we must HAVE a GEM500 4 stage gearbox. so this is me begging/searching for a chance to get one. they’re out of stock on andymark’s website right now. any help would be much appreciated.

I’ve got one. If I recall, it’s 2 stages. I can’t say we’re ever likely to use it with the advent of Versaplanetaries, so I wouldn’t mind giving it up to someone with a use for it. Let me know if you’re interested.

Speaking of Versaplanetaries, have you considered one of those? You can stack it up to whatever ratio you’d want. 3847 has posted instructions on how you could mount a CIM to a Versaplanetary. Looking at the Load Ratings, a 1/2" hex output shaft is good for atleast 112 ft-lbs under simple loading. That seems to be the limiting factor, as the 1/2" keyed shaft is rated slightly lower, and the 3/8" hex and CIM outputs are rated much much lower. 112 ft-lbs is some good bit more than the 66ft-lbs you thought you needed with two PG188’s.