Got an old Mackie mixer to use as part of a video job. Of course it was missing a volume slider for one of the channels. Here is the replacement I created built from dimensions taken from one of the original sliders.
Check out the volume knob I just made for the same mixer
After review of the printed piece I will probably go back and change it up a bit. This one works well but it isn't close enough to the originals for my liking.
Printed with MakerWare default high quality settings. Printed upside down with supports. I did have to do a bit of cleaning up of the supports and used a small file to get the indents good enough.
It is a bit snug on the metal part of the slider but it fits well.