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Unread 21-11-2008, 08:31
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AM Super Shifter -- pneumatic attachment

Last night we finished the chassis for our prototype and were reassembling the transmissions after filing down the pin that was sticking out of the dog gear. We noticed the following behavior, and we have no reason to believe this is the first time this has happened:

- If we put the transmission in neutral without a pneumatic piston attached, the gears freespun beautifully, even without re-lubing anything
- If we put the transmission in gear without a pneumatic piston, the gears still freespin, though the dog gear likes to get caught on the face of a gear on that axle, so it really becomes hard to get it in gear -- lubrication should help this
- If we attach the pneumatic piston, all of a sudden the gears stop freespinning. We're still able to turn them without much effort.
- If we prevent the shaft of the piston from turning with the pneumatic attachment as we spin the internal gears, the gears get MUCH harder to turn.

In essence, the inside of the pneumatic piston is spinning with the transmission and we want to stop it... so the question is how? If we force it to stop, it feels like something in the piece that attaches to the piston is binding up. Since there are 2 tiny screws that look like they could take a little while to get off and on, we didn't want to proceed without guidance. Anyone have any ideas?
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