Potentiometer help


I'm new here and pretty new to home audio/electronics projects so please bear with me here.

I created my first clock amp a while ago using a Minty Amp kit, an Ikea alarm clock and some other bits and bobs. Here are some images:




I failed to take progress pics so couldn't create an instructable for the project but I plan to do that with my next one (I've had a lot of interest with people actually asking to have them made to order - which Mr Minty Amps, Bob Hickman, assures me is cool).

Anyway, so I've ordered the parts to make another clock amp but decided to get some extra bits from Maplin.co.uk this time. In teh first amp I used a 250k guitar potentiometer for the volume but it's not sensitive enough and really only has three settings (full, quiet and silent). So, this time I ordered this 1k pot from Maplin.

When the pot arrived it has a 50mm shaft which is too long for my project. I assume I can just trim the shaft down so long as I'm careful since it's only plastic. Is that right?

Also, because it's not a guitar pot, the shaft is smooth and so the standard control knobs I have will not fit it. Does anyone know of a (cheap) type of control knob that will fit such a pot? I really don't want to have to glue a knob on there.

Thanks for your help.

NachoMahma9 years ago
. You should be able to trim the length of the shaft without any problems. Try not to put too much stress on the pot body while trimming - I'd suggest clamping the excess shaft in a vise and using a fine-toothed hacksaw, coping saw, &c. . You can get knobs with a set screw that will work. Should be able to get them at the same place you got the pot. You may be able to soften the plastic with a heat gun or blow dryer and force the knob on, but I'd save that for the nothing-else-works stage. . BTW, most volume pots have a logarithmic taper, not linear.
clockamps (author)  NachoMahma9 years ago
Thanks very much for your advice NachoMahma. Much appreciated. Will the fact that I've bought a linear rather than logarithmic pot matter do you think?