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Unread 04-05-2016, 19:29
Oblarg Oblarg is offline
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AKA: Eli Barnett
FRC #0449 (The Blair Robot Project)
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Re: pic: Input Stage Wear

Quote:
Originally Posted by hectorcastillo View Post
Can you explain inboard/outboard?
The WCP gearboxes allow four CIM pinion sizes, from 11-tooth to 14-tooth. The 11t and 12t are one pitch diameter, and the 13t and 14t are another. In order to accommodate this, the gearboxes can be mounted in one of two orientations: "inboard" for the smaller pinions, or "outboard" for the larger (this is accomplished by having a overlapping holes for one of the two bolts that holds the CIM in place).

Unfortunately, it seems the rather rough nature of this year's game produced sufficient forces on the motors that they managed to move from inboard to outboard (there's not much metal preventing this from happening between the mostly-overlapping mounting holes). Once that happens, the gear spacing is no longer correct and grinding/wear is unsurprising.

To prevent this at future events, we wrapped the groups of 3 CIMs on each gearbox in hose clamps, which worked like a charm.
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Member, FRC Team 449: 2007-2010
Drive Mechanics Lead, FRC Team 449: 2009-2010
Alumnus/Technical Mentor, FRC Team 449: 2010-Present
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Last edited by Oblarg : 04-05-2016 at 19:31.
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