Posted by Ken Wilson at 1/27/2001 4:50 AM EST
Engineer on team #248, FEMEX, from Philadelphia Girls High and PECO Energy Company.
In Reply to: U-bolts
Posted by Patrick Dingle on 1/27/2001 1:26 AM EST:
: There was some brief discussion on the General Forum about using U-clamps/bolts to mount the drill motors to the robot. Let’s say, hypothetically, that our team is using the drill motors, and hypothetically, we are considering clamping them on with large U-bolts. Does anyone have any wisdom about mounting motors with U-bolts? Or is it a bad idea in general?
: Patrick Dingle
: Team 639 - Ithaca High School & Cornell University
: [email protected]
I don’t think you’ll get enough contact area between the oddly shaped housing and the u-bolt ID. The clamping force will be distributed over these small areas > stress > housing distortion >clamp relaxation> bolt retorquing. All that could compromise alignment of your drivetrain.
Our first year - we milled the handles off to achieve a flat mounting surface (housings sitting upright)and confined the now oval shaped base within a lexan plate slotted to receive hose clamps (2). There was some loosening, but worked OK.
Last year we again milled handles off and milled a flat in the speed selector plate for an inverted mount. We then cut 1" HDPE block with slots to capture the handle bore and bolted through it to the baseplate A lot of effort - but worked well. We also incorporated Dr. Joe’s motor mod (HIGHLY RECOMMENDED) and dispensed w/ the clutches.
This year we’ve taken the advice of Drs. Johnson and Baker in mounting our drill assemblies, resulting in a structurally sound, accessible and cooler (thermal and visual aspects) design.
If all that is way too much work - I’d use hose clamps first and u-bolts only if I could “gasket” the clamping surface of the housing to better distribute the clamp force over the surface.
e-mail me w/ any questions @ [email protected]
call me kenny TEAM 248 - Phila. HS for Girls