Pioneer A-88X balance knob

Seems like my Pioneer A-88X lost a couple of knobs! The original knobs are made of
aluminium, and they apparently used plastic inserts in the alu buttons for the splined connector to the potentiometers. Over time, the glue separated and the aluminium knob was lost somewhere :(

This is the balance knob, recreated from blurry pictures on the Internets as I had no knob to copy.

The tolerances when printing this are very tight. Just changing the print speed caused caused the splined connector to become too loose or too tight. I spent way to much time re-printing this for a perfect fit! In the end the fit was a bit loose, so I just put some tape over the splined hole and pressed on the knob. Don't press to hard on the knob though! Might damage the potentiometer. The alternative would be adjusting print settings or size by 0.1mm and printing again. And again, and again :)

If you like me just lost the alu buttons, the original black plastic splined inserts still affixed to the metal potentiometer splines, you could always print this with a 8mm round hole instead of the splines and glue the new knob to the original plastic insert.

I printed this with 0.08mm layer height and ironing. While you can tell the new knobs apart from the old, it's good enough for me!