My first amp project: A small 386 IC based battery powered guitar amp. All the components were either scavenged or picked up at radio shack. Total cost was around 15 bucks. The enclosure is a .50cal ammo can, 4 1/2" 8 ohm full range speakers in series. Powered at 12v by 8 AA batteries. I was a little frustrated that I couldnt find a 5k pot with a short stem 🙁 but it's not hard to shorten the stem and epoxy a knob on.
It sounds OK... has volume and drive adjustment, and will get everything from clean to super overdrive.
It sounds OK... has volume and drive adjustment, and will get everything from clean to super overdrive.

Looks like it means business!
Those potstems are meant to be cut to size I think, you can just put a knob on there with a set screw to fasten it. If you want to be extra careful, file a flat spot where you put the set screw (i never do).
Measure the stem before ordering knobs, it's usually either 1/4" or 6mm, although there are some other diameters as well (4mm for instance).
Those potstems are meant to be cut to size I think, you can just put a knob on there with a set screw to fasten it. If you want to be extra careful, file a flat spot where you put the set screw (i never do).
Measure the stem before ordering knobs, it's usually either 1/4" or 6mm, although there are some other diameters as well (4mm for instance).
Looks like it means business!
Those potstems are meant to be cut to size I think, you can just put a knob on there with a set screw to fasten it. If you want to be extra careful, file a flat spot where you put the set screw (i never do).
Measure the stem before ordering knobs, it's usually either 1/4" or 6mm, although there are some other diameters as well (4mm for instance).
It's best to cut the shafts BEFORE you fit the pots, so you don't strain them. I've always cut plastic shafts with side cutters, and obviously metal ones with a hacksaw.
Likewise I never file flats on the shaft either - pots normally have either a flat all the way down, or no flat at all.
I'm just planning on cutting it with a small abrasive wheel, so it shouldn't put much strain on the pot when I trim it.
I get those crappy pots at Rat shack when I am desperate , I usually just cut the shaft down to size with my Dremmel and use a knob with a screw inset ...... cool looking amp though .....
Cheers
Cheers
I would use the paper masking tape (blue in the US, pale yellow overhere) to make sure nothing can make it's way into the pot (even though the fit of shaft and bearing is pretty tight, and filled with grease).
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