Gibson ES345 pickups problem

[MarkusBass]

I'm trying to rewire Gibson ES345TD from stereo version (with Varitone switch) to mono version. This does not seems to be difficult but I found out that the pickups are out of phase. When I turn the neck pickup by 180 degrees, the pickups are still out of phase. What do I need to do to switch the phase of one of the pickups?





Mark

[pdf64]

As you found, turning it around won't change its signal polarity.
A PU will need to be opened up, ie cover removed; then, either reverse the wires going to ground and hot, or turn the magnet over.
Neither are jobs for the inexperienced / fainthearted, on an expensive / vintage guitar.

[MarkusBass]

Thanks. That what I heard - someone turned the magnet over to solve the problem in similar case. I'll see if I can do it.

Mark

[pdf64]

OK, good luck then.
Swapping the wires around may be simpler / less invasive than messing with the magnet.
eg you may get away without needing to re-pot the PU.

[52 Bill]

It looks to me like an late '60s or early '70s model with pat number pickups. Probably no wax on those pickups, unless it was done at a later time.

Removing and replacing the covers is the hardest part. I suggest that you grind off solder (no heat) to remove them. Then you loosen the four screws that hold the bobbins down until the magnet can be pushed out from under them. Flip the magnet and then reassemble.

You will need to solder the cover back on. I push the cover down onto the assembly and then use a wooden clamp to hold the sides of the cover tight to the baseplate while soldering.

[MarkusBass]

Thanks Bill, you are right - there is no wax. Removing the cover was very easy. It seems that the magnet can be pushed out from under pickups. Changing wires would mean replacing the tape but I don't have such a tape for replacement. Also, I'd like to keep the changes to minimum so that they can be reverted (it looks like the guitar is a collector's item). The wiring change is done in such a way that it can be easily reverted to the original wiring.

Mark

[MarkusBass]

I flipped the magnet and now both pickups are in the same phase. Actually, it was quite easy - both opening the pickups and flipping the magnet.
I haven't check how the guitar sound with amp but I expect some improvement.
I wonder whether I should clean the white compound that is on springs and pickup covers. This is some kind of oxide. Should I try to clean it?
Thanks for help.

Mark

[pdf64]

Well done.
The white stuff may be coming from the zinc in the plating.
I'd squirt some WD40 type cleaner lube on to a cloth and wipe the affected parts / areas to clean it off and stabilise it a bit.

[MarkusBass]

The white stuff is "wet storage stain", or "white rust": https://en.wikipedia.org/wiki/Wet_storage_stain - a form of zinc corrosion (the surface was not protected). I'll try to clean it and treat the springs with oil.

Mark

[MarkusBass]

I cleaned the pickup parts with citric acid.
Cleaned springs (before and after):

Assembled guitar:


I think that the guitar sound much better now. I'll ask the owner for his opinion.

Mark

[52 Bill]

Seeing the entire guitar now makes me think that it is older than I had thought, T top pickups, plastic bridge saddles.

If you have a directional compass, it is fairly easy to figure out the magnet orientation from outside of the case. Just don't bring the compass too close to the polepieces or you can reorient the compass magnet, making it worthless for any future use.

Does the owner prefer the Peter Green reversed neck pickup?

[MarkusBass]

I think that the neck pickup is not reversed. It seems to me that the guitar was assembled like this at the factory. The wire from the pickup is at the lower end of the pickup - look at the very first photo. The pickup can be reversed (because the wire is long enough to do it) but this is the way it was designed and assembled initially. This also makes me think that the guitar is quite old. There is a label inside the guitar - it looks very old but there isn't any date on it.

Mark

[52 Bill]

There is a label inside the guitar - it looks very old but there isn't any date on it.

Mark

Is the label oval, orange and black or is it rectangular, black white and purple? These are clues to dating the guitar. Serial number and pot codes will also help.

I've never seen any Gibson with the neck pickup oriented that way from the factory. Well, maybe a Peter Green Custom Shop Les Paul model.

[MarkusBass]

The label is rectangular, black white and purple:



The pots look like this:



It's to late to check them now. I think there were some numbers on them but I don't remember a year.

Mark

[MarkusBass]

OK, on the old pot I see "70 029". Is it a year and week number?