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Re: pic: Poly-carbonate Gearbox Plate
You can't afford to use the kind of aggressive lightening patterns in polycarb that you can in aluminum, particularly for gearboxes. Polycarbonate just isn't rigid enough. I would not pocket the gearbox at all, and maybe add more counterbores standoffs to give you rigidity. All of the rules for pocketing aluminum gearboxes just don't apply here.
To answer your question, could you run a shaft in polycarb without a bushing... Maybe, but probably not at 1200 RPM. You could easily heat the polycarbonate up to its glass transition point wih aggressive driving and things would get ugly fast. Even if it works though, your efficiency will tank beyond the point where it's worth it. An encoder is a terrible reason to throw out ball bearings...
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Last edited by Chris is me : 03-04-2015 at 12:49 AM.
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