Wax potting covered humbuckers

[zizyphus]

Hey all

I have on particular humbucker that's rather microphonic, and I'd like to re-pot this bad boy.

It started life as a double black bobbin, open-coiled 'bucker. I've swapped the magnet, half-aired it, and put on a gold cover, but now she squeals like crazy.

I have everything I need to do a normal wax potting job, but I've never repotted covered humbuckers before. My Google and youtube searches have shown how to re-wax, and then re-cover the pickup, but that leaves the obvious issue of air between the cover and the rest of the pickup. When I've removed covers that came stock on humbuckers, I've usually seen wax filling that space. How does it get there? Do I just wait until the cover is on to pot it? If so, why isn't there wax all over the cover? If not, what do I do?

Thanks!

 

[bigcupholder]

Re: Wax potting covered humbuckers

Did it only start squealing after you put the cover on? Did you put tape over the slugs to prevent the cover from vibrating against them?

I've put covers on several pickups before and never needed to repot them, despite regularly playing at high volume with high gain. I put electrical tape over the slugs, then squeeze the cover on tight while soldering it in place.

The electrical tape is soft enough that it absorbs any vibrations in the cover, basically like wax would. Wax is for getting INSIDE the coils. For the cover, tape is fine.

Sent from my SM-G970W using Tapatalk

 

[zizyphus]

Re: Wax potting covered humbuckers

Did it only start squealing after you put the cover on? Did you put tape over the slugs to prevent the cover from vibrating against them?

Yes, and yes :/

 

[AlexR]

Re: Wax potting covered humbuckers

Its usually pressure of clamping that has an effect too. So whether or not you choose to pot, you need that high clamping pressure from both top and sides (simultaneously) to make sure of its firm attachment.

 

[Mincer]

Re: Wax potting covered humbuckers

Most pickup companies will repot and put everything all back together. If they are open.

 

[rainsong86]

Re: Wax potting covered humbuckers

Buy some paraffin wax. Set up a double-boiler: one container with near-boiling water and one container (big enough to dip pickup cover into) with a couple chunks of wax. You'll want the wax to heat til it's about the consistency of honey or maybe a bit thicker so that when you dip the cover into the wax a good amount of it will stay on the cover and not leak out the 6 pole piece holes. Raise the screw poles, clamp pickup tight, solder and wipe clean.

Could also put a piece of tape over the top of the 6 pole piece holes and drip some melted wax into the cover and proceed from there.

Those who just tape off the clug coil often use some silicone paste between the tape and cover

 

[thrill74]

Re: Wax potting covered humbuckers

If you haven't already done it, it's the same process. Just get your bowl of wax hot in a pot of hot water, then dip the the pickups in. I cover my humbuckers, and solder them into place, then pot them. The wax will easily go around the cover and baseplate all through the coils. The cover isn't air tight or anything. After the bubbles stop coming out then I pull them and turn them on their legs. Some of the wax runs out but not a terrible amount. I use a paper towel to clean the tops and sides of the covers. Then install!

 

[GuitarDoc]

Re: Wax potting covered humbuckers

Wax pot AFTER the covers are on.

 

[David Garner]

Re: Wax potting covered humbuckers

I seriously think it's the cover. If you want to find out, take the cover off (you need to anyway if the cover is the problem) and see if they still squeal.

I bet they won't.

I had this issue with a nearly brand new 57 Classic + I bought off eBay. When I took the cover off, the problem disappeared. When I re-installed the cover properly, it stayed disappeared.

 

[Erlend_G]

Re: Wax potting covered humbuckers

Same problem here- with metal covered "dog ear" P90's - in a Epi Wildkat.

I've decided to unsolder the covers, and apply a gentle amount of "silicone based mass"- that's rubbery in consistency- to dampen the cover.

Because it feeds back like crazy- even at low volumes- but stops when I hold a finger on top of the cover.

Please keep me in touch if you fix the problem!! I'm going to "make surgery" in a weeks time- just need the right tools and dampening material.

-Erlend

 

[Erlend_G]

Re: Wax potting covered humbuckers

^^ just had a thread about just this. So is curious to hear the results.