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Unread 15-01-2016, 11:17
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Engineer at Medrobotics
AKA: Dr. Joe
FRC #0088 (TJ2)
Team Role: Engineer
 
Join Date: May 2001
Rookie Year: 1996
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Re: Smallest SS Gearbox - COTS or Custom?

Quote:
Originally Posted by jkelleyrtp View Post
I'm trying to fit some gearboxes into our frame and space is very precious at the moment. I was wondering what the most compact way to add a gearbox onto the robot would be. We have some CNC capabilities so making custom gearboxes wouldn't be too bad, but it would be our first time doing so. We're also worried about an 11-72 tooth reduction not holding from the impact loads in this game, so unless there's a great testimonial, I'd rather do dual stage. (Leaning towards single stage but want to make sure it's robust.)
11:72 in one stage is not your problem. Tooth strength is the problem and you can build 12:72 gearsets that will fail on your first crossing and others that will last the whole season with nary a complaint.

What is the face width of the gears involved? What Pitch? What is the size of the wheel you are going to be driving with that 72T gear.

By the way, chain done right can be many many times stronger than gears (largely do to the fact that multiple teeth share the load). Can you fit a stage of #25 chain? 11:72 is fine in one stage of chain (~1"OD to ~5.9"OD)

Dr. Joe J.
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