Quote:
Originally Posted by squirrel
just curious, have you calculated the maximum torque on the rod? low grade 3/8" hardware usually breaks at about 40 ft lbs or so.
|
It's geared for about 57 ft*lbf of torque at stall.
Also, there'll be a tensioning mechanism that occupies the space inside the tubing, enveloping both the bolts and the shaft. This'll
Quote:
Originally Posted by Dick Linn
It looks like you are going to depend on the nuts being very tight, rather than having keyways or a hex shaft or pins to keep the wheel and the sprocket from loosening and spinning with respect to each other.
|
I suppose that's one way of describing it. I'm relying on the coupling nuts' inability to move along the thread -- that is, to tighten or loosen -- to drive the shaft. I'd just as soon use hex shaft as this ridiculous scheme if I could decipher some way of sticking a hexagon into a small round hole.
It assumes that it's easier to drive the robot than it is to strip the threads -- which may not be at all true.
This is an (over?)extension of a method that was used to drive FIRST robots years ago. The 2003 KoP included an adapter that threaded onto the Bosch drill output and was secured in place by a left-handed screw. The adapter accepted a 5/8" dia. keyed shaft on the other end, so maybe that's my clue that what I'm trying to do here is a bit stupid.
I'm a terrible machinist and usually the person responsible for explaining to students and mentors alike what processes they need to follow to make the parts I design. If I don't know how to make something, nobody does; so I often stick to what I'm most comfortable with.
I appreciate everyone's help a lot. I'm a bit dense sometimes and don't always think things through until long after I've invested myself in making them work.