The never-ending wiring grounding issue... Help!

[infiniteposse]

Hi all-

I've been working on an unusual parts-caster for a while now that I've dubbed the "Fuglycaster." I've gone through several iterations of pups trying to get the right string height dialed in since this Bigsby creates unusual string break/neck angle issues and now I'm just trying to get the wiring done.

The problem I keep having is massive ground hum. In an attempt to help the issue, I've shielded the guard, a first for me. I also redid all of the wiring with cloth wire and replaced all of the older pots as well. I've run a ground between all 4 pots.

Places I'm unsure/may have made a mistake:


The P-90 I'm using I got 2nd hand with no info. I think it may be a Frailin. It's got 3 wires, one hot (white), one ground (black) and then one loose wire that I've got no idea what to do with. It runs with the black/white cable through the main black cable and is just a loose wound wire. I'm not sure if I should tie this to ground or wrap it in tape or what?
Have I done the pickguard shielding correctly? I'm tying the shielding to the bridge at the moment, which seems a little odd to me. I haven't worked on this in a few weeks and I'm sure there was a reason for my doing this, but I can't recall what I read that suggested this approach. Also, for the record, I was unable to shield the cavities under the pups as the tape wouldn't stick to the cavity at all. Does this defeat the purpose of the ground?
The hum seems to diminish when I touch the output jack/cable end. I've double-checked and that is wired correctly. Any idea what could be at issue here?

Hopefully the pics will illustrate how things are wired at the moment. My apologies for the soldering job. I'm still fairly new at this and with this guitar there's been a lot of soldering/unsoldering. It's not a pretty site.

Any assistance is greatly appreciated!

http://i18.photobucket.com/albums/b149/infiniteposse/Fuglycaster/IMG_0417.jpg

http://i18.photobucket.com/albums/b149/infiniteposse/Fuglycaster/IMG_0418.jpg

http://i18.photobucket.com/albums/b149/infiniteposse/Fuglycaster/IMG_0422.jpg

http://i18.photobucket.com/albums/b149/infiniteposse/Fuglycaster/IMG_0423.jpg

[RvChevron]

First of all, I think you are describing the "buzz" instead of the 60 cycle hum which all single coils have and cannot be removed with shielding.

It's normal if the "buzz" is reduced somewhat by you touching any metal parts that are connected to ground.

The loose wire of the p90 is actually the shield of the pickup and should be soldered to the back of the pot.

All of the shielding foil, bridge metal, pot casing, and ground wires should be connected. Make sure the pot shaft/casing is tightly mounted to the pickguard and is in tight contact with the foil.

I would run a wire from the back of the pot (instead of from the copper foil) to the bridge.

Also, it can reduce the buzz further if you also sheild the body cavity and connect the sheild to the pickguard foil.

Shielding paint is easier to apply than foil in the cavity.

BTW, does the copper tape have conductive adhesive? if not, solder the seam/joint of each overlap.

If you have a meter, check the contiuity. Touching any part of foil anywhere in one end and touching any metal part or bridge in the other end should get you the "beep" which means they are all connected.

Cool arm rest btw, where did you get it?