Pot diameter adaptor

[sunbeast]

This seems unlikely, but...
I recently took the pots/ active preamp out of an old bass I have to change them out with some 500K pots/ passive electronics. My problem is that the new pots are a different diameter on the threaded length. Meaning that I can't fit the new pots in without drilling larger holes in my bass body. I don't have a problem with drilling the holes, but I would like the option of replacing the preamp someday.

My question- is there some sort of adaptor that can be put on a pot with a skinny diameter to make it fit snugly in the larger diameter holes in my bass?


Thanks, Karl Zickrick

[luknfur]

Originally Posted by sunbeast

This seems unlikely, but...
I recently took the pots/ active preamp out of an old bass I have to change them out with some 500K pots/ passive electronics. My problem is that the new pots are a different diameter on the threaded length. Meaning that I can't fit the new pots in without drilling larger holes in my bass body. I don't have a problem with drilling the holes, but I would like the option of replacing the preamp someday.

My question- is there some sort of adaptor that can be put on a pot with a skinny diameter to make it fit snugly in the larger diameter holes in my bass?


Thanks, Karl Zickrick

FWIW:

welcome to the world of bass transplants where no two components are alike and there's no such thing as a drop-in (less something specifically designed - like a Retro for Fender).

Pot stems vary in height and diameter as well as smooth or with a variety of splines; threads are different type, number, and diameter; pots bodies vary in size, ohm ratings, linear/logarithmic; and I'm probably leaving something out. All of which makes pots, nuts, washers, and knobs non-transferable to an alien environment.

There are no "adapters" but you can just find a tubing that will both fit over the shaft and fill the void and cut it to length.

Unless you figure on doing a lot of swapping I would get the proper pots. Unless it's a beater bass, you're probably going to tear up the finish drilling. Plus once you get it drilled, you may find the threads aren't long enough to thread a nut and the knobs don't fit (the fun never ends). Depending on what was in the active unit, you can probably use those. Usually the volumes are all that need to be changed as often they're 25K - but often they're not. Personally, I haven't found enough difference tonewise between a 500K and 250K pot to bother with. Altering cap value will make exponentially more difference.

[sunbeast]

I've actually done this in the past by wrapping a couple of layers of masking tape around the threads and then cutting the excess that stuck out of the body, but I thought there might be some more"professional" way to go about it.

The original preamp pots are all connected to a circuit board and are also all weird values. It seems like a lot of smaller companies just use pots of their own random diameter (usually much smaller than normal), while I guess companies like Fender and Gibson kind of set the standard with their sizes (as much as there is a standard anyway) so are more easy to guess/ more compatible with available sizes.

I guess I'll just stick with the masking tape method, you can't see it anyway with the knobs on.

Thanks, Karl Zickrick

[John East]

Originally Posted by sunbeast

This seems unlikely, but...
I recently took the pots/ active preamp out of an old bass I have to change them out with some 500K pots/ passive electronics. My problem is that the new pots are a different diameter on the threaded length. Meaning that I can't fit the new pots in without drilling larger holes in my bass body. I don't have a problem with drilling the holes, but I would like the option of replacing the preamp someday.

My question- is there some sort of adaptor that can be put on a pot with a skinny diameter to make it fit snugly in the larger diameter holes in my bass?


Thanks, Karl Zickrick

I use some general purpose O rings which are made of a hardish rubber.

The smaller pots tend to be 7mm diameter and the larger, 9mm or 3/8". The O rings I use are a snug fit on the 7mm threads, you have to roll them on, and snug fit in 9mm or 3/8" clearance holes too. As they're rubber, they tend to compress slightly, centering the pot on the oversized hole.

So just a case of looking for an O ring supplier, somewhere selling nuts, bolts and screws often have them, and finding a size which does the job.

John