[Madison]

Originally Posted by Dick Linn

Is there any way to upgrade the design to a 1/2" or 5/8" shaft? Something with enough meat in it to allow pinning or a shaft key or just more torque in general? I can remember using an adapter off the old drill transmission to couple a shaft. However, that was before the final stage of gear reduction, and hence subject to a lot less torque.

We don't have broaches or an arbor press, so I try to avoid keyed shafts whenever I can. If it comes to that, we'll just use dead axles again in 2007 as we've done for the last several years.

Edited to add: I've been poking around the 'net for a few hours trying to see what I could find about calculating the torque required to strip a nut or bolt of its threads. I've come across some things suggesting good practice -- that the bolt shaft should fail before the thread strips -- but nothing explicitly offering an answer to the question. I understand that the answer is a function of the nut and bolt material and the shear area. The shear area is, in turn, a function of the number of threads engaged between the nut and bolt. Beyond that, I think that my brain is fried and I'm missing a connection somewhere that'd let me equate the output torque of my gearbox to the force required for the coupling nut to strip the threads on the shaft.