I had a basic idea of what I wanted to build (to ape a proven design), but didn't have any detailed specs. My arbitrary rule for this was that I had to use the blade from a dead can opener, so I dug through my stashes of material that would work. The actual shapes were dictated by happenstance and correction of errors, of which there were many.
The steel rod is from a printer, the maerial for the nut is from a piece of steel that was in an antique toolbox I inherited, the knob is from a miniature dimmer from another project), the brass plate and knurled bar are leftovers from a guitar project I haven't posted here yet (I made all of the hardware from brass. Posted it to https://www.facebook.com/permalink.p...00020053728764).
I tried a new-to-me technique on this mostly because it seemed like fun. I machined the bore in the 1/4" plate and the shoulder on the barstock to an interference fit and heated it for a temporary slip fit. I wasn't quick enough, and it tightened up before it was fully seated, but a few light taps with a hammer did the trick. Note to self: be quick. It still let me get the knurl up against the fence part.
I didn't bother to remove all of the scratched before polishing, so it's a Monet, but I'm OK with that.