2 to 4 wire conversion

[fenderbender]

I recently picked up an Epiphone LP (a beautiful 2003 Korean made model that looked like it was never played) and will be performing the HBD mod to it when all the parts show up. However, I suspected that the pickups in it were wired with two leads and after removing the control cover plate and a pickup I found this was correct. Now the mod to four wires is pretty straight forward from what I can tell, but there's one fly in the ointment - they are wax potted.

My question is this: Is there a safe and sane way to remove the wax so one can get at the wires for the conversion? I've read that naptha can be used to remove the wax without damaging the pickups but I'm curious to any other methods as well.

[newey]

Here's a link that recommends using a blow dryer, holding the pickup with a pair of tongs . . .

www.ehow.com/how_7215434_do-remove-wax-potting-humbucker_.html

Mind you, I haven't ever tried this, but if it works, it has to be better than naptha.

Some pickups are potted in an epoxy resin which is virtually impossible to remove. Are you sure yours are wax-potted?

[fenderbender]

Absolutely certain. I took the metal cover off and it's indeed a wax potting. Was melting like mad when the iron touched the back plate. Thanks for the link.

[cynical1]

One thing the link does not tell you is that this can be a messy procedure...and not always as effective as advertised.

While this will get a good deal of the wax out, much like leaving the guitar in the backseat of a closed car in Phoenix in August...it will not get it all. It might get enough to help you with your mod.

Suggestions:

1.) Find a cookie sheet and cover it with aluminum foil. Trust me, after an hour with the blow dryer you are going to wander a bit, so this gives you a larger drop zone, and the aluminum foil prevents spousal induced bruising to the cranium.

2.) Find a pair of Vice Grips, or locking pliers to hold the tab on the humbucker. Even hair dryers can make the pickup too hot to handle, especially the 1000+ watt models on their highest setting.

3.) Do what most American's do...use some toxic high VOC chemicals...carbon tetrachloride or hexane should work... But seriously though, I'm not sure on the naphtha part, but mineral spirits do dissolve paraffin based waxes. Putting the pickup in a small sealed jar full of mineral spirits, then suspending in a pot of warm water will speed the process. Keep in mind, if any chemical additives are added to the potting wax this process my be an exercise in just standing there...

4.) Revert to less toxic chemicals. Turpentine will dissolve beeswax, but not too sure about paraffin based waxes. Goo Gone works pretty good on wax as well, but may get a bit pricey.

5.) Finally, the wax melts at around 135 degrees, so you don't need excessive heat to remove the wax. Getting a bit too carried away in the introduction of heat to the pickup may deform or distort the plastic bobbin.

Hope some of this is useful. For reference, the car in Phoenix thing in August really does work...

Happy Trials

Cynical One

[wolf]

Having done a lot of 2 to 4 wire conversions, I have found that the wax is the smallest of the problems. If you can get to the wires, that's fine. If you have to remove the wax to get at the wires, this can easily be done with your fingers. You do not have to remove every last microgram of wax.

Here's my webpage on converting 2 wire to 4 wire humbuckers www.1728.com/guitar1a.htm

(It does not mention wax potting at all.)

[jcgss77]

I'm with wolf. If you haven't already pulled off your outer layer of tape, I would do so and see if your series wire is exposed from there. No heat needed, and removing the wax, if I am correct, could increase the chance of the pup going microphonic. I think that I have also read that you can't re-pot a de-potted pickup. Is that correct?

[gfxbss]

Maybe one of the deities will strike me down on this, but to my knowledge, you can re-pot a pickup.

I have potted quite a few pups w/o any issues, though non of them had been depotted to my knowledge.

Tyler

[cynical1]

You can re-pot a de-potted pickup, provided it was paraffin wax potted to begin with. It all happily remelts together. Remember the car in Phoenix story...those re-potted just fine. The bass case, on the other hand...

HTC1

[fenderbender]

After having the cover off the neck pickup I will probably attempt wolf's method. I can't see any reason to remove more than necessary. The lead wire was visible through the wax so it's a given on what end to start picking the wax off.

If nothing evil happens after the fact I'll re-pot them via the double boiler method I read about here. Err...or maybe it was the original GN site. Anyway, as a fall back I did venture into the local shop today and seen they had a set of Seymour Duncan Hot Rodded Humbucker Pickup Set (SH2N and SH4). I may have to get them just because.

[cynical1]

If you're just going to chip a small piece of wax off you can stick the pickup in the freezer for a few hours. That'll make the wax brittle and it'll just pop off.

HTC1