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I'm getting some loud scratchiness from an old MXR Microamp. If deoxit is the solution, where do I spray it?
 

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I put a paper towel around the area being sprayed as there usually is a bit of blow back. Use the red 'straw' tube for sure. Additionally, give the straw tip a squeeze with some pliers first ( you only need to do this once) to make it easier to get it right in the pot slot. You only need a tiny amount of Deoxit so be quick on the trigger!
 

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You'll have to open it up and spray it inside the body of the pots. There's usually an open slot just below the tabs.
I think it is better to spray in the small opening on the edge of the back of the pot if it has one. Angle the straw slightly left or right. Rotate the pot a dozen times to work the Deoxit around.
 

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Often, it is quite possible to simply lift the tabs on the pot that allow the back cover to be removed, wipe the grime off the resistive strip, and put the back cover back on.

Pot scratchiness is produced by discontinuities of contact between the wiper and the resistive strip. Those discontinuities can come from multiple sources, only one of which is external dirt. If the pot is older (which yours apparently is), some of the discontinuities can come from a buildup of internally-created grime, produced by the wiper rubbing and scraping against the resistive strip. Think of that grime as being equivalent to little bits of pebbles and the like being lifted off the top of an asphalt highway, that now sits like extraneous dirt and gravel. Of course, once you sweep all that away (which a schpritz of Deoxit will do), you're still left with all the pits and imperfections in the surface of the road and the resistive strip.

I'm a perpetual booster for a product that comes out of Thorn Hill called Stabilant 22 ( Stabilant.com ). It used to be sold to audiophiles under the brand name Tweak many years ago, but got repackaged and rebranded when it became apparent that it had much wider applicability than pre-amp/power-amp connections. Where Deoxit, and similar products are contact cleaners, Stabilant is a contact enhancer. It forms a viscous never-drying coat between two points of contact that function almost like a liquid solder joint. As I hasten to remind folks, in the world of electrons, a micron gap between two contacts may as well be the Grand Canyon. Stabilant fills that gap with an electro-conductive polymer. I use it on my pots, but have used it to rejuvenate all sorts of things where imperfect contact was being made: Nintendo cartridges, phone SIM cards, flash-drives, IC sockets, and old TV remotes. Truly remarkable stuff. My attention was drawn to it by my buddy Phil Bova, who runs a pretty busy studio in Ottawa, and has 6" analog faders on one of his boards that he has to keep dead quiet and crackle free. He swears by the stuff. I tried it out and was converted. A number of guys I've corresponded with who run pro repair benches swear by the one-two punch of a schpritz of Deoxit to remove the grime, and a dab of Stabilant to fill in the micro-pits.

It is NOT cheap, and not all that easy to find ( Stabilant.com : Distributors ), but a small amount will do you for years and years. It can be diluted with isopropyl alcohol so that it spreads more easily, and creates larger volumes. Amazon.com: Stabilant 22, 5ml Kit Makes 30ml of 22A - 22: Everything Else

I'll just add that, since it never dries, you can't build up layers to fill up large gaps. So a pot that has recently become scratchy is easily "cured". If one happened to be in a Cream tribute band and played White Room and Tales of Brave Ulysses on the same wah, thrice nightly for the last 40 years, Stabilant is not going to be enough, and the pot will need replacing.

Of course, sometimes it really IS cheaper and easier to just replace the pot.
 

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Often, it is quite possible to simply lift the tabs on the pot that allow the back cover to be removed, wipe the grime off the resistive strip, and put the back cover back on.

Pot scratchiness is produced by discontinuities of contact between the wiper and the resistive strip. Those discontinuities can come from multiple sources, only one of which is external dirt. If the pot is older (which yours apparently is), some of the discontinuities can come from a buildup of internally-created grime, produced by the wiper rubbing and scraping against the resistive strip. Think of that grime as being equivalent to little bits of pebbles and the like being lifted off the top of an asphalt highway, that now sits like extraneous dirt and gravel. Of course, once you sweep all that away (which a schpritz of Deoxit will do), you're still left with all the pits and imperfections in the surface of the road and the resistive strip.

I'm a perpetual booster for a product that comes out of Thorn Hill called Stabilant 22 ( Stabilant.com ). It used to be sold to audiophiles under the brand name Tweak many years ago, but got repackaged and rebranded when it became apparent that it had much wider applicability than pre-amp/power-amp connections. Where Deoxit, and similar products are contact cleaners, Stabilant is a contact enhancer. It forms a viscous never-drying coat between two points of contact that function almost like a liquid solder joint. As I hasten to remind folks, in the world of electrons, a micron gap between two contacts may as well be the Grand Canyon. Stabilant fills that gap with an electro-conductive polymer. I use it on my pots, but have used it to rejuvenate all sorts of things where imperfect contact was being made: Nintendo cartridges, phone SIM cards, flash-drives, IC sockets, and old TV remotes. Truly remarkable stuff. My attention was drawn to it by my buddy Phil Bova, who runs a pretty busy studio in Ottawa, and has 6" analog faders on one of his boards that he has to keep dead quiet and crackle free. He swears by the stuff. I tried it out and was converted. A number of guys I've corresponded with who run pro repair benches swear by the one-two punch of a schpritz of Deoxit to remove the grime, and a dab of Stabilant to fill in the micro-pits.

It is NOT cheap, and not all that easy to find ( Stabilant.com : Distributors ), but a small amount will do you for years and years. It can be diluted with isopropyl alcohol so that it spreads more easily, and creates larger volumes. Amazon.com: Stabilant 22, 5ml Kit Makes 30ml of 22A - 22: Everything Else

I'll just add that, since it never dries, you can't build up layers to fill up large gaps. So a pot that has recently become scratchy is easily "cured". If one happened to be in a Cream tribute band and played White Room and Tales of Brave Ulysses on the same wah, thrice nightly for the last 40 years, Stabilant is not going to be enough, and the pot will need replacing.

Of course, sometimes it really IS cheaper and easier to just replace the pot.
I want to be in a Cream cover band!
 

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I removed the back, and got right into the little hole at the back of the pot. Worked like a charm.

I also once had a pedal causing other problems. I sprayed the whole thing with Deoxit, pulled the cables and sprayed them too. Problems gone.
 

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I try turning the knobs at least 100 times first

But yeah, if Deoxit doesn't work, your pot is probably shot
 

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Discussion Starter #10
I removed the back, and got right into the little hole at the back of the pot. Worked like a charm.

I also once had a pedal causing other problems. I sprayed the whole thing with Deoxit, pulled the cables and sprayed them too. Problems gone.
I opened up the back and shot the pot, the input/outputs, and the on/off button. All is good now.

Thanks everyone.
 

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I suspect Deoxit will do a better job, simply due to the chemicals it contains intended to remove oxidation. If the problem is simple (i.e., simply a matter of "washing" out dirt), it will likely be enough. If the problem is more complex it might be enough, but might not. Either way, the Nexxtech stuff won't hurt anything.
 
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I suspect Deoxit will do a better job, simply due to the chemicals it contains intended to remove oxidation. If the problem is simple (i.e., simply a matter of "washing" out dirt), it will likely be enough. If the problem is more complex it might be enough, but might not. Either way, the Nexxtech stuff won't hurt anything.
mhammer is THE DR. of pedals.
 
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I'm not quite sure how to take that! o_O Do you mean that I actually DO know stuff, or that I put on a good front about knowing stuff? :confused:
Oh I never thought about that... you definitely know your stuff. Best ever!
 

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I'm sure any electrical contact cleaner will do the job and not harm anything
 

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Would spraying Deoxit on just the volume control post and turning it a few time help at all? I have a few controls on my old Peavey PA that are a little noisy once in awhile.
 

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Would spraying Deoxit on just the volume control post and turning it a few time help at all? I have a few controls on my old Peavey PA that are a little noisy once in awhile.
I've had that work for me sometimes. It's worth a shot (pun intended), Especially on electronics where overspray isn't a big deal. If it doesn't work, you haven't lost anything and may still have to open it up.
 
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