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cclrobotics / lhr-mechanical

Repo for keeping mechanical related items.
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Check and tighten CNC fasteners. #3

Open griswaldbrooks opened 8 years ago

griswaldbrooks commented 8 years ago

All of the fasteners for the CNC need to be checked and tightened. There are already bolts that are seen to be loose.

ddigor commented 8 years ago

By the CNC I take it you mean the mechanical framework built out of 80-20 hardware. That mechanical framework is indeed flakey. It was disassembled, quickly, by one set of people as it was being removed from Arcturus, then reassembled, weeks later, by a different set of people, from inadequate photos, and then disassembled and reassembled for the trip downstairs. There are several possible ways to assemble the 3 axis corners, and some of our reassembly choices may have been poor. Some cross pieces are a few millimeters too short, and the pair of 40x20 rails carrying the two stepper motors that must run in sync are 5-10 degrees off vertical, top skewed inward. This suggests that some fastner replacement, as well as tightening, may be required.

The rail hardware is all metric 80-20, but the T-nuts and associated screws are a mongrel assortment. I purchased quite a few extra metric T-nuts and screws, which are with the spare hardware at the unit.

griswaldbrooks commented 8 years ago

The 80-20 framework, exactly. It was referred to as "the CNC" because that's how Pedro referred to it. Major assembly issues might be something that we make a ticket about in the future, but for now I think that we can run what we have, just to verify that the steppers work, after we tighten the chassis. I'll make a ticket about the alignment.

birdilicious commented 8 years ago

I have tightened all CNC fasteners except for those of the cross-member beam. @griswaldbrooks and @tamarum will make metal shims for the cross-member beam, because it's shorter than the 80-20 beam above it. When we get the shims hopefully for the next meeting, the cross-member beam can be assembled back into the CNC structure/motion axis, and then the rest of the fasteners can be tightened.

griswaldbrooks commented 8 years ago

@birdilicious also fixed one of the x axis 80/20 beams which was not connected to the vertical beam correctly. She also tightened the existing bolts and added a few new ones.