I made a new main swinger pivot yesterday, I spent way too many hours thinking about the best way to make it.
I really dislike shafts with a fastener at each end, you can never do them up properly.
I thought about machining a hex on one end or something, but then I'd need to have more tools or some special custom tool that I'd need to have in the tool box.
That blows.
A couple of bourbons later and wondering aimlessly in the shed, oh look over there!
I've had a 3/4" breaker bar for ever and never use it. It just so happens to be dia 19.95mm perfect.. they are hard AF and chrome.
So, M8 in one end, drilled 12.5mm from the other to get some weight out, turn a step and machine a washer, weld it onto the step. Turn down the head of a M8 SHCS, cut the thread off and weld that inside the washer end.
Machine a piece of Ti as the doey uppy end and bamm.
Just need 2 x 6mm Allen keys and axle is done.