Contact cleaner

[Jazzer2020]

Yesterday I opened up my pot cover on my Gibson SG to check some things out.

First off I had just discovered a new problem with my pickup selector switch.

 

When I selected my bridge PU, there was little or no sound. That's never happened before.

Also, when I had the selector set to bridge/neck, the sound was basically the same as my neck pickup sound.

 

Finally, the neck pickup sound has not been the full-bodied sound that it used to be for quite some time now.

 

I thought something might be wrong with the wiring, but everything looked fine.

 

I got out a new can of contact cleaner (lube + cleaner) that I have been saving for my Fender amp's pots (haven't gotten around to that cleaning job yet).

Then I sprayed some of the lube/cleaner on the PU switch and wiped it in.

 

Before I closed up the cavity I tested out my guitar.

I was very pleasantly surprised with the results.

 

The bridge PU problem was fixed.

The middle selection was a genuine mixed sound (neck/bridge) not like before.

The neck PU selection was giving me the full sound that I had lost for some time.

 

Why am I writing about this?

Two reasons.

 

Did I use the right contact cleaner for the selector switch?

Should it be a contact lube/cleaner or just a contact cleaner?

 

I'm also wondering if I should clean the switches on my other guitars?

Do you folks do this only when you have a problem or regularly as "preventive medicine'?

 

TIA

 

 

 

 

[onelife]

The important thing is not to use a contact cleaner without lube on the pots.

 

Cleaner/lube is okay on the switch. You may have been able to clean out the obstruction with air as well,

 

I wouldn't do the other switches unless they become a problem.

[DeepEnd]

I never use it unless it's needed. The last time was when I set up an Ibanez for a friend. I was initially going to just replace the pots but then I tried contact cleaner on principle. Worked like a charm.

[Radar-Love]

1.) Did I use the right contact cleaner for the selector switch?

 

2.) Should it be a contact lube/cleaner or just a contact cleaner?

 

3.) I'm also wondering if I should clean the switches on my other guitars?

 

4.) Do you folks do this only when you have a problem or regularly as "preventive medicine'?

 

 

 

1.) Since you have an unsealed pickup selector switch on your SG, in theory, you should not use a lubricating cleaner on an unsealed switch because, in theory, there might be dust particles floating around inside the body cavity which will eventually adhere to the lubricant on the contact surfaces and cause contact resistance.

 

As long as you've never noticed any Gibson factory wood dust residue inside the pickup or control cavities, I wouldn't be concerned with the theoretical consequences of dust particles somehow gumming up contacts. However, if by chance you have noticed wood dust when opening your SG's cavities, I would suck it out with a vacuum cleaner and finger rag. Gibson normally does a good job of removing wood dust residue after all milling steps have been completed. I've personally seen the Gibson Nashville factory in operation and they have multiple QC checkpoints looking for wood dust and chips.

 

Otherwise, you had a common case of corrosion buildup and you cured the problem -- for now (see #4) -- and that's what's important. For the average person that doesn't use their guitar as a bludgeoning tool, humidity in the storage environment is far and away the the principle cause of potentiometer and selector switch contact problems.

 

 

 

2.) For pots, *definitely* use a lubricating cleaner. I would certainly use the same cleaner on a switch with open contacts -- it works. My favorite is DeOxit Fader Lube F5, with DeOxit D5 as a less expensive alternative.

 

 

 

 

 

3.) Might as well. In fact, if you're storing all of your instruments together, chances are fairly high that you already have significant corrosion on pots and switches on the other instruments.

 

 

4.) Contact cleaning preventative maintenance once every 12 ~ 18 months should be adequate, unless you live near the ocean and/or play out regularly. Maybe then, you need to schedule pot / switch cleaning maintenance every 6 ~ 9 months.

 

 

 

[Grant Harding]

I have to get some of that stuff. My strategy is to flick the switch back and forth about a hundred times to get the oxidation off. Usually works, but this seems like a much better idea.

[Radar-Love]

My strategy is to flick the switch back and forth about a hundred times to get the oxidation off...

 

 

Cycling works better with pots and Strat/Tele selector switches.

 

As for "cleaning" pots in a pinch, when contact cleaner is unavailable, you can take off the knob and wrap string or even dental floss around the shaft and cycle the pot back and forth a few dozen times vigorously and basically burn through the corrosion and polish the wiper contact and resistive surfaces back to 100 percent. Just take care to not violently slam the wiper into the stops as you could actually break the wiper off internally.

 

Some really nasty cases of pot corrosion basically require a vigorous cycling along with pot cleaner to get the conductive surfaces clean.

[Jazzer2020]

Thanks Radar and the others for your tips!

Radar, you mentioned "unsealed pickup selector switch" and also "switch with open contacts" with two different approaches for each. How are the two switches different? I'm not clear on that.

 

To me (as you mentioned) my SG selector switch is clearly unsealed. But the switch also has open contacts. Now it's open/now it's closed.

[Radar-Love]

...you mentioned "unsealed pickup selector switch" and also "switch with open contacts" with two different approaches for each. How are the two switches different?

 

 

An unsealed switch has open contacts, as in the contacts are out in the open (i.e. -- easily visible). A sealed switch does not have any open contacts.

 

Some sealed switch units may have a tiny opening in their casings to allow for the type of contact cleaning maintenance we have been talking about, but most are hermetically sealed to (hopefully) not allow moisture to enter and corrode bare metal contacts.

 

 

 

[Jazzer2020]

 

 

As long as you've never noticed any Gibson factory wood dust residue inside the pickup or control cavities, I wouldn't be concerned with the theoretical consequences of dust particles somehow gumming up contacts. However, if by chance you have noticed wood dust when opening your SG's cavities, I would suck it out with a vacuum cleaner and finger rag.

 

I think I know what might have sped up the residue collection on my switch.

A month or so ago I did some work on my SG neck (sanded it down).

I didn't take any special precaution to cover the pickups or the pot cover on the back of the guitar.

Dust could easily have found its way into the cavity.

As a matter of fact I recall using wet paper towels to get out some dust I found there.

 

 

 

OK, here are the parts I mentioned where it seems you are giving conflicting tips:

 

1.) Since you have an unsealed pickup selector switch on your SG, in theory, you should not use a lubricating cleaner on an unsealed switch...

 

So for an unsealed switch (open contacts) you are recommending not to use a lube cleaner.

 

2.) For pots, *definitely* use a lubricating cleaner. I would certainly use the same cleaner on a switch with open contacts -- it works. My favorite is DeOxit Fader Lube F5, with DeOxit D5 as a less expensive alternative.

 

But here, for a switch with open contacts you are recommending a lube cleaner.

 

Do you see why I am still confused?

 

[WRGKMC]

The lube doesn't hurt the open switch but it may make it easier to knock out of place because the pole has mineral oil on it. It can also attract dust more quickly with an open switch.

 

Non residue has its issues as well. It can make the switch toggle pole so dry it can even bend the contacts. The pole usually has a plastic tit to prevent this but when they get old I avoid using a zero residue cleaner which is mostly alcohol. Alcohol can cause certain plastics to crack too so I avoid using it.

 

The best way with those relay switches is with no cleaner at all. You use a contact burnishing tool and clean the contacts manually. This is how its done for all relay type devices and unless you have experience in that old technology and do the job properly.

 

You first loosen the switch and pull it free from the body. Then you use a burnishing tool which is an ultra thin ultra fine file like device. Its thin metal with some super fine grit on each side. You place it between Two contacts, press the contacts together against the blade then draw the blade out. This polishes the contacts and removes tarnish dirt, arching or carbon (in high voltage situations which this isn't)

 

Its allot like polishing frets to give the contacts a mirror finish. You don't want to use coarse grade sandpaper because it can leave scratches that can collect dirt. It only takes a few seconds with the proper tools and you don't have issues with chemical cleaners.

 

 

 

 

[Jazzer2020]

 

The best way with those relay switches is with no cleaner at all. You use a contact burnishing tool and clean the contacts manually. This is how its done for all relay type devices and unless you have experience in that old technology and do the job properly.

 

 

... Its allot like polishing frets to give the contacts a mirror finish. You don't want to use coarse grade sandpaper because it can leave scratches that can collect dirt. It only takes a few seconds with the proper tools and you don't have issues with chemical cleaners.

 

 

Thanks WRG, I didn't know about this option.

 

[Freeman Keller]

I just stumbled on this and want to add that while I was working on my friends Goldtop LP I asked him what happened to the top near the bridge. He said "I sprayed contact cleaner into the pots and some got out on the finish." He then added some terms that the forum won't allow me to repeat.

 

I'm an electrical engineer - for years my technicians have used various kinds of cleaners and lubricants on electronic components. Just make sure it is safe for your particular finish or remove the pots from the guitar, clean them, remove all excess and put them back in.

 

[Jazzer2020]

I finally got around to cleaning the pots. It's a long story for the delay.

Anyhow, I could still use some tips because it was far from successful.

 

One of the reasons I was delaying the operation was because of the tediousness of it.

 

(Sorry for the confusion, but this a cleaning of pots in my Fender Vibroverb amp).

 

So the amp is open. I remove the chassis.

I locate the pots, unscrew them from their washer/nuts etc.

 

There are four pots in a row. I was going to clean them all once I had the chassis open but it was such a hassle just to get at these four I decided to limit my cleaning to just them this time.

 

Three of the four pots were closed/sealed except for that tiny opening on the back.

Unfortunately the pot that really needs cleaning wasn't the open one.

The contact cleaner can came with a plastic tube to insert into the nozzle and squirt into whatever needs to be cleaned.

 

The problem was that the tube, even though it was quite slim, still didn't fit into the hole on the pots.

I got it as close as possible and sprayed several times, getting more cleaner outside/on my fingers than in the pots probably.

 

I gave each pot a good workout, turning the dial back and forth.

 

Then I re-assembled everything and tested it.

Unfortunately when I turned the problem pot (the volume pot) it was just marginally better.

It still had cracks and pops and most annoying, the sound from the amp was still breaking up.

 

First question, how can I get into those tiny holes in the pot to spray properly?

Second question, could the breaking up sound from the amp not be related to this dirty pot?

What is the likelihood that it is a tube going? Would you have the same distorted/breaking up type sound if a tube was going?

 

TIA

[Les Paul Lover]

If that pot has that much crackle, in my experience, any application of contact cleaner is only a temporary improvement. Even if you clean it up, the crackle usually comes back pretty fast. Whilst you have the amp open, I would simply replace the pots. Only 3 wires per pot to desolder and resolver. Whilst you're at it, you could make.sure your volume pot is a log pot (B), i know lots of fenders cone with linear pots, they aren't well suited to volume applications.

[Jazzer2020]

If that pot has that much crackle' date=' in my experience, any application of contact cleaner is only a temporary improvement. Even if you clean it up, the crackle usually comes back pretty fast. Whilst you have the amp open, I would simply replace the pots. Only 3 wires per pot to desolder and resolver. Whilst you're at it, you could make.sure your volume pot is a log pot (B), i know lots of fenders cone with linear pots, they aren't well suited to volume applications.[/quote']

 

Thanks LPL that was very helpful!

I'll try to pick up a new log pot soon.

I didn't look at the pot connections, but these guys were cramped pretty tightly onto their individual board.

 

One more question about the tube question.

A couple of times in the past few months, when I was testing out the amp to see what was causing the distorted sound, I plugged into the normal channel (no reverb/vibro).

That channel had no distorted sound at all.

 

Is that conclusive that the problem is with the other channel's volume pot?

If a tube was going, would it affect both channel's sound?

TIA.

 

 

[Jazzer2020]

I just made some very satisfying progress!

 

I was trying to find out the pot specs for my volume pot online, but couldn't find anything.

I called a few local music shops but they don't stock the stuff (would need an electronics store, but closed here now).

 

Then I watched a Youtube video of this guy who has the same amp as mine, and he was showing how to clean the pots. He's a bit of a clown but I noticed he didn't detach the pots from the circuit board to get and the back side hole. He just sprayed down the front shaft.

 

So I re-opened my amp chassis and decided to do the same.

I started with some regular cleaner, then some cleaner-lube.

Gave the volume pot a good workout and then plugged in my guitar with the amp still open.

 

Wow!

Two things happened.

First I was getting a clean sound, no distortion/break-up etc. Yeah!!!

 

Second (and this was really interesting) I was getting some cool sounds in the kitchen.

Now I always play in the living room which is carpeted.

So getting the different sound in the kitchen was to be expected.

 

But... (this is what really surprised me) I had the amp's speakers facing away from me. I was behind the amp and it sounded really cool.

When I moved around to the side, and in particular to the front of the amp, the sound now had much less bottom end and didn't sound nearly as good as from behind!

 

I've taken some photos of the locations and will post later on.

Quite a happy development, I must say!

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[Les Paul Lover]

Excellent news. If it starts again and you do consider replacing it, ignore my comment re log pots being the B pots. That depends on the company manufacturing them. Alpha pots for exemple are from Taiwan, and those excellent.pots are A for audio or log, B for linear.