…there was a music stand that had its knobs broken. I was asked to repair a music stand that had 3 broken adjuster knobs. The old ones were a mismatched set of plastic knobs that had been over-torqued, over-used, and eventually broken. I choose to spin a few knobs out of 1.250” 6061 aluminum round bar. The design is fairly simple and straight forward. I made them round to help prevent over tightening.
I drilled and tapped the knobs to accept a 6mm stud. I used a tapping tool that I made awhile back to help get the threads straight. The tapping tool consists of a piece of 1” solid alloy bar with a hole drilled about 2/3 way through. I machined threads into the rod to be able to spin on an old ½” Snap-On drill chuck I had. I then machined a smaller rod to be able to fit down the center of the previously machined rod. I machined a chamfer into the end of the center rod to accept an old wheel bearing ball bearing I had laying around.
I then cross drilled the main body so that I could slide a handle through it. I mounted the whole assembly into the tail stock of the lathe which then allows me to tap straight. I do not use the tool under machine power; I tap all my holes manually. Once I have the hole tapped and a stud installed spinning the knob up on the lathe confirms my tapping is straight.
I cut studs from a 3’ length of Stainless Steel 6mm x 1.0 ready rod. I then double nut the studs and bottom them into the tapped holes. I then lock then bottomed stud in with SS 6mm jam nut. The corners of the nut then get machined off to give it a clean look also so that the knob will fit into the music stands plastic guide.
My original plan was to sandblast and then paint the knobs flat black so that they would blend in. However once I was done the Scotchbrite finished knobs looked good all on there own, I think I will leave it.