Are you suggesting that the failure is not happening out the outside radius? or possible there is some necking occurring which diminishes the radius? I think this is a possibility, however, to get a number that is relatively close to what I'd expect, the radius would need to change from 0.0335in...
For my test I put the fixed end in a drill press and the rotating end in a torque gauge and twisted the shaft (by hand, with the drill press off) until it came apart. I measure at almost 9.6 in-lbs every time i repeated the test. Obviously the drive shaft shears off at the necked down area...
The design is already set for its application. I am trying to better understand how to make it work reliably. The actual problem is that both FEA and hand calculations don't line up with the actual part.
Looks like this may actually make my problem worse. If the actual stress is higher than...
Thank you for the welcome. I've used PF for years, but finally came across an issue that i didn't see a solution to already.
I could use a ratchet, but that wouldn't work for this application. I'm really interested in just leaving the part behind if that torque is overloaded.
I am trying to design a drive shaft that breaks when i apply a specific torque to protect fro over torquing. I made a few samples, and now i am trying to compare the results to my equations. My problem is, none of the equations seem to match the actual results. Your help would be appreciated:
I...