Scratchy volume pots

[McGlamRock]

Both of my go-to teles are suffering from scratchy pots. I’ve used Deoxit (and a couple other contact cleaners) and the “scratchy-ness” has lessened, but there’s still very audible noise every time I use the volume knob.

Could the pots just be going bad?
Seems like a possibility on the older one; it’s 13 years old and I play it and use the volume knob a lot. But the other one is only 4 years old.

Any ideas? I’ve searched this forum and watched a lot of YouTube videos.

 

[Happy Enchilada]

You need to check wiring - you might have a short or something needs grounding.
Check all points from pickups to output jack.
I'd do that before replacing the pot. And if it comes to that, CTS or Bournes pots only.

 

[dougstrum]

Hey if deoxit doesn't clean them best thing is to simply replace them.

 

[McGlamRock]

 

[Killing Floor]

Deoxit sparingly.

SPARINGLY cannot be overstated. Do not use the fire hose. Spray the hose into a cloth and the small drop left on the end of the hose you can wipe on the shaft. Then wipe it off. Then cycle the pot a bunch of times. Too much Deoxit will damage the pots. It’s better to use way less than you think.

 

[FortuneTele]

Are you working it in good?

Set shaft to 5 (mid-way), quick spray left and right, then turn cw all the way, then ccw all the way...20 times. Let it set awhile, repeat. If that doesn't fix it, you may need a new pot.

 

[schmee]

Lubricated cleaner, often plain electronic cleaner will make the shaft or the bushing tight especially if it's a plastic shaft. If one cleaning doesn't last: replace it.
But yeah, make sure something else isn't causing the static not a worn pot. That seems more prevalent in amps though.

 

[Boreas]

For a VERY short time I was restoring some of my old stereo amps. Several places on the interweb cautioned about DeOxit. They stated some of their formulations are fairly acidic (corrosive) and can damage especially sensitive electronics. I don't know whether it is true or not, but going back and looking at some solder joints that I sprayed inadvertently, they were definitely more dull - like it was etched. I tend to use DeOxit for sliders in my pots to lubricate them a little, but again - sparingly.

The carbon tracks in guitar pots are not indestructible. They can be damaged by heat, solvents, grit, and time. A quick spray of DeOxit shouldn't cause any harm, but the results may be short-lived if the track is wearing thin. Unless your pots are in a valuable vintage instrument, I would lean toward just replacing them. I believe some people know how to repair/rebuild the carbon track in "valuable" pots, but in original vintage instruments, simply removing the pot to rebuild it can effect the value of the guitar. Cork-sniffers and collectors can be pretty finicky.

Plus, you can buy several new pots for the price of a can of DeOxit nowadays.

 

[philosofriend]

Deoxit sparingly.

SPARINGLY cannot be overstated. Do not use the fire hose. Spray the hose into a cloth and the small drop left on the end of the hose you can wipe on the shaft. Then wipe it off. Then cycle the pot a bunch of times. Too much Deoxit will damage the pots. It’s better to use way less than you think.

This is true of Deoxit D5 which is a strong chemical concoction that deoxidizes corrosion on metal switch contacts. It also can attack some plastics. The Deoxit F5 (F for "faders") is simply a mild solvent plus lubricant that is designed for flushing out dirt. With F5 you can spray as much as you think you can afford.

The Caig company that makes Deoxit recommends F5 for potentiometers, not D5.

 

[Holy smokes]

Bizarre. Both with the disease one used the other 4 yr. Old unused. First for me. 0-10 x 100 see what ya got. Good luck

 

[schmee]

Just add this pedal to the scratchy pots and your cat will love you!

 

[Geo]

Guess you could also try to determine if the noise is coming from another source. I had a big static charge build up
earlier this year that showed up moving the controls and also through the amp. Even the pickups sounded really weird
from it. It was from static buildup on the pick guard (a dryer sheet removed it). Another time it was in the pickup selector
switch which I sprayed with contact cleaner to remove.

 

[CoolBlueGlow]

If the pots are not that old, and nothing vintage, (or if excessively vintage and valuable then disassemble them and thorougly clean them out. You have nothing to lose. Look at the carbon tracks and the contactors under a maginfying glass or stereo microscope. Gently clean. Reinstall lubricant if it is dried out. Put the pot back together. Generally, I find they can be repaired by proper cleaning.

I often use Hosely's Brass Cleaner - which is nothing more than powdered oxalic acid. (guess what is in Caig and those other "deoxit" sprays?) Hosely's does not contain an abrasive, unlike Brasso, etc. I've written about this extensively on the Antique Radio Forum. (Those guys are crazy over there, btw You can buy a big container of Oxalic acid one time and never buy spray deoxit cleaner ever again.

Here are a few microphotographs of an NOS rotary switch I used as an example. This switch has the same basic metallurgy as the contactors in your typical guitar switch or the wipers in a potentiometer. These contact were heavily corroded from 15 years exposed storage - again this was an NOS part - and then cleaned with oxalic acid. As you can see in the following photographic progression, it does a nice job. Only use it on the wipers, not the carbon track. Works on your CRL-1452 or similar pickup selector switch too.

NOS rotary switch after 15 years of storage corrosion

Same switch, contact close up 20x

Same switch, lightly cleaned with oxalic acid - no polish, just wipe on/wipe off, and flush with denatured alcohol

Same switch, contact close up 20x (after 200 switch cycles)

As you can see, the oxyacylic acid does a nice job of chemically removing the funk without damaging the contact.


Of course, if they can't be fixed because the carbon track is bad, then then buy the same exact brand and style of pot, take the wiper and carbon track out of the new one and put your old can cover back on the new wiper / carbon track assembly. Keeps your date codes intact.

Will keep the vintage nerds happy come some day future.

 

[McGlamRock]

UPDATE
A little late with this, but it seems the volume pot scratchiness was caused from using the 2nd input in my little peavey amp. I plugged my tele in the 1st input and the guitar’s scratching stopped. Same thing on my other tele.
I don’t understand what the issue is exactly- if the problem is with the amp why did adjusting the guitar’s volume knob make noise? Bizarre.

Anyway, really appreciate everyone’s suggestions- you all definitely helped me a lot. Thanks!

 

[Boreas]

UPDATE
A little late with this, but it seems the volume pot scratchiness was caused from using the 2nd input in my little peavey amp. I plugged my tele in the 1st input and the guitar’s scratching stopped. Same thing on my other tele.
I don’t understand what the issue is exactly- if the problem is with the amp why did adjusting the guitar’s volume knob make noise? Bizarre.

Anyway, really appreciate everyone’s suggestions- you all definitely helped me a lot. Thanks!

Dirty/loose input jack?

 

[StitchBass]

I don't know anything about the input circuitry of Peavey amps, or the difference between inputs 1 and 2,
but if there is a small amount of DC voltage present on input 2 it could cause scratchiness when the volume pot is adjusted on the guitar.

If you have a multimeter you could plug a guitar cable into input 2 and see if there is a small voltage present between the tip and the sleeve of the cable. The amount of voltage present could be very small, just a few millivolts.

Connect the meter to the cable connector, and check for voltage at zero volume on the amp, and at several increased amp volume levels.

Connect the meter with the amp off, so you don't get any loud noises due to connecting the meter