Wiring help for an old Teisco

[kensell]

Hello. I just picked up an old Teisco 4 pickup guitar and need a little wiring help. This is my first project guitar, so any help would be appreciated. Most of the wiring looks good, but the tone pot and associated capacitor need to be reconnected. There was also a wire going from the positive side of the input jack into a hole that leads to the bridge cavaity. The wire wasn't connected to anything. The hole is obviously for a string ground, so I'm guessing that a previous tinkerer stuffed the wrong wire in there.

I've done a lot of looking at diagrams, and couldn't find any that look like a clear fit for what I have. The biggest thing I'm having problems with is where to put the cap for the tone pot. The tone pot is already grounded, so I guess that means I have to put the cap on the positive side.

Anyway, here's my best guess.

1) Put a capactior between the positive side of the input jack and the middle tone pot connector.

2) Run a ground wire from the back of the volume pot to the back of the tone pot.

3) Run a new ground wire from the strings to the back of the tone pot.

4) Connect the negative side of the input jack to the back of the tone pot to complete the ground.

I could also un-solder a thing or two and go with a more modern setup. I've attached a picture, which hopefully will help.

Thanks,

Ken

[olddawg]

It looks like someone wired this for a volume control only at some time. You will need a bridge ground. Any schematic with one tone ond one volume control will work for you after the switch like a telecaster, an Lp Jr, etc.

[kensell]

Thanks olddawg. I put a new cap in, 50s style, added the ground wires and off I went. It sounds pretty good. The 4 side by side rocker switchs for the pickups cut in and out occasionally, so I've got a little clean up to do there, but everything else seems to be in good shape.

Thanks again,

Ken

[olddawg]

A spray or two of Caig Deoxid or Cramolyn contact restorer should resolve those issues.

[David Schwab]

WD-40 also works wonders when real contact cleaners wont.

[olddawg]

WD-40 also works wonders when real contact cleaners wont.

I guess WD-40 might be appropriate in some instances where rust has frozen steel parts on switches. IMO WD-40 is more well suited for marine engines and such having seen it irrepairbly destroy more electronic systems than I would care to recount. I've used it to free up pot shafts and the like, but it has a tentancy to migrate to stain finishes and destroy plastics and other petroleum based parts. In electromechanical applications I always wash the stuff out after using it, then replace the appropriate missing lubricants.

[David Schwab]

I guess WD-40 might be appropriate in some instances where rust has frozen steel parts on switches. IMO WD-40 is more well suited for marine engines and such having seen it irrepairbly destroy more electronic systems than I would care to recount. I've used it to free up pot shafts and the like, but it has a tentancy to migrate to stain finishes and destroy plastics and other petroleum based parts. In electromechanical applications I always wash the stuff out after using it, then replace the appropriate missing lubricants.

The reason I tried using it was I have a Behringer mixer that I once spilled Pepsi on. I disassembled the mixer and cleaned all the faders, but most of them were totally useless. I tried everything, including distilled water to get the sugar residue out, and all the usual (and expensive) contact cleaners, which just made maters worse.

I was getting ready to either chuck the mixer or replace the slide pots when I decided to try some WD-40. A few squirts and a bit of sliding.. and that fixed it right up!

I'm not sure how oil would degrade plastic, but I have never had an issue with it. One of the things it is listed as doing is cleaning electrical contacts, since it displaces water. (The name means Water Displacement-40th try)


Main ingredients, from the material safety data sheet, are:
50%: Stoddard solvent (mineral spirits, somewhat similar to, but not the same as, kerosene)
25%: Liquefied petroleum gas (presumably as a propellant, carbon dioxide is used now to reduce considerable flammability)
15+%: Mineral oil (light lubricating oil)
10-%: Inert ingredients
The German version of the mandatory EU safety sheet lists the following safety relevant ingredients:
60-80%: Heavy Naphtha (petroleum product), hydrogen treated
1-5%: Carbon dioxide

[Chuck H]

"WD-40 also works wonders when real contact cleaners wont"

The reason WD-40 is not a good contact cleaner is that it contains soft oils (they do not evaporate or dry). This means that when dust or particulate from wear get into a pot or jack it gunks up. Also, it is flammable. Even once the solvents have evaporated away. This means that when it gunks up in high voltage circumstances things can get pretty hot (as in "Quick, someone hand me an extinguisher. My amp is on fire").

However... If you have used it to good effect when the standard stuff wouldn't cut it, there was nothing to lose. So in that case I would say go ahead. But use standard contact cleaner afterwards to clean out some of the WD-40.

As mentioned, and as with any contact cleaner, don't get any on the finish. For that matter, it occures to me that since WD-40 is an oily solvent it can penetrate wood and continue to migrate. Eventually causing adhesion problems with finishes (chipping, peeling). I have some experience with this. So it would be best to keep wood contact to a minimum also.

Chuck


P.S. FWIW when I was young I used WD-40 a couple of guitars and never experienced any problems for it. But now that I'm more experienced (old). I have seen a few cases where it has caused problems. So when I saw it suggested I felt a duty to intercede.

[olddawg]

The reason I tried using it was I have a Behringer mixer that I once spilled Pepsi on. I disassembled the mixer and cleaned all the faders, but most of them were totally useless. I tried everything, including distilled water to get the sugar residue out, and all the usual (and expensive) contact cleaners, which just made maters worse.

I was getting ready to either chuck the mixer or replace the slide pots when I decided to try some WD-40. A few squirts and a bit of sliding.. and that fixed it right up!

I'm not sure how oil would degrade plastic, but I have never had an issue with it. One of the things it is listed as doing is cleaning electrical contacts, since it displaces water. (The name means Water Displacement-40th try)

I was a bench tech and head tech /supervisor for a large professional and consumer audio and video electronics repair facility for 25 years. At one point I removed all the cans of WD-40 from all 22 techs and kept one can at my bench. You see any seasoned tech know that there is a difference between fixing something and making it work. I was tired of the call-backs and unit replacements we were forced to do because of WD-40. If you get it anywhere near a tape path, drive, rubber parts, plastic, wood etc you are in big trouble.

It is good for marine engine's ignitions because it does displace water. You can start a stubborn diesel with it because it is flammable. It makes a great flame thrower btw. I once burnt a 2 foot hole in the shop carpet flooring trying to incinerate a cockroach with a can of it from 3 feet away.

Slider pots are a special case. IMO the only way to truly clean them is to flush them out with whatever works and replace the factory lubricant with the original viscous stuff (like Vaseline) that comes in a syringe to inject into the pot. (or even take the pot apart to swab an even layer on the element) That stuff is hard to find and I don't remember the name for it. I have never seen it available at any electronic supply houses. I got it with a part number from the manufacturers at one time. If you clean and lubricate a slider pot any other way they have a tendency to dry out, scrape, and freeze up in hours, days or weeks. If you notice, a new slider will have stiffness to its movement that disappears after cleaning. The thick factory lubricant will bring that back along with a reliable repair. WD-40 has its place. You just have to know what that place is and be very, very careful with it.

[David Schwab]

WD-40 has its place. You just have to know what that place is and be very, very careful with it.

Absolutely agreed. I never ever used the stuff on pots before, or any electronic parts. I had it for the usual things... locked up screws and squeaky hinges! And removing rust.

But I was desperate to get the faders to work.. they all had big dead spots in the middle. I didn't want to throw out the mixer, or replace all the faders... Now the mixer works fairly well. I was surprised how the real contact cleaners didn't help, and actually made matters worse.

But this was a special case. Contact cleaners aren't made to get Pepsi residue out.

[jamiecowan]

would anyone care to help me figure out this goofy wiring for this awesome guitar?
I think it is an et 4-40
I am just having trouble with the pickups, I am not sure about how the wires go to the switches?

Thank you !