Wiring First Attempt - Went Well, but One Question

[horrorbiz]

First post, glad to have come across this site. Let me say that I've never attempted to do any kind of 'beyond your typical setup' maintenance to my own guitars.
That is, until I started reading the guitarnuts website and was hooked. So, guitarnuts lead to reading the wiring tutorials on stewmac.com and the electronics section of "The Guitar Player's Repair Guide". I finally decided to give it a try myself and re-wire one of my cheaper guitars - an epiphone '62 sg standard reissue.

Here's what I did:
1. Bought an SG/Les Paul wiring kit from stew mac
2. Followed the wiring diagram for Les Pauls (using alternate volume control wiring) that came with the wiring kit (www.stewmac.com/shop/Electronics,_pickups/Supplies:_Wiring_kits/1/Wiring_Kit_for_SG/Instructions/I-1217.html#details)
3. Other than doing EXACTLY as the above wiring diagram dictates, I also got the copper shielding tape and shielded both pickup cavities and the control cavity.
4. I then ran a wire from the neck cavity shielding to the bridge cavity shielding
5. Ran a wire from the bridge cavity shielding to the control cavity shielding
6. Ran a wire from the control cavity shielding to the tone control pot case that is upper-right hand side of the diagram.

So, the guitar sounds much better and I'm very happy with my first attempt, but there's one odd thing that is happening and I'd love to understand why.

When I put the pickup selector switch to activate the bridge pickup only and I turn the bridge pickup volume all the way down, I can still hear some sound coming through the amp, which goes away if I turn the neck pickup volume all the way down. Same thing happens in reverse: pickup selector switch activates neck pickup only, turn neck pickup volume all the way down, still hear sound that only goes away when turning the bridge pickup volume all the way down.

So, it seems like the bridge/neck pickup is bleeding into the sound even when the opposite pickup is activated.

Anyway, great forum, glad to be here.

[newey]

Horrorbiz-

I don't have an answer for your query, but I'll give you a big "Hello and Welcome!". This will then bump your question back up and someone will see it.

If I have to venture a guess- and that's all this is- your volume controls do not allow either pickup to be fully "off" in this scheme. No-load pots would presumably solve the problem, but I suspect there's an easier way. So, please await further expertise.

[ashcatlt]

Thanks for stopping by.

Unfortunately, I don't have a good answer for your question. The way you've got it wired, the unused pickup should be open (and therefore silent) when the switch is flipped away from it. The selected pickup is shorted (across itself) when its volume is turned all the way down. This should equal silence. Unless there's something wrong with your pots and there is some fairly significant (more than an ohm or two) resistance even when turned all the way down.

I suspect that you are actually hearing the other pickup - the one you've switched away from. Why this happens I can't be sure. I do know that when I first wired up my strat (3 humbuckers, no pots) I couldn't get total silence out of it. The rotary switches which control the individual pickups left their pickups open in the "off" position, but when I turned all three off, I could still hear a very thin version of the sound coming through the amp. I never did figure out what wasy going on there but I managed to fix it by shorting across the unused pickups. I'm afraid that option will be impossible with the switch you've got.

[JohnH]

I also suspect it is the other pup you are hearing. You could check this by tapping poles with a screwdriver tip, to see which pickup is making this small sound.

Just check you have the ground connections to the pots lugs, but assuming so, then it is maybe just a capacitive coupling betwen wires as they go up and down the internal cavities. Does each pickup travel through its own screened wire between the cavities?. If you are using unscreened wire internally, or a multicore wire, it could explain this effect, based on this alternate wiring scheme.

Im not a fan of the alternate LP wiring. I think it does bad things to tone as you turn volumes down, and also the output becomes very high impedance at low volume, which can maybe explain this spurious picking up of the switched off pup. The standard LP wiring probably wont do this.

John

[horrorbiz]

Hey guys, thanks for the welcomes and all the good information. I really do appreciate it.
Based on this, I'll check the ground connections. Also, I'm not sure how to answer the question about the pickup wires. When I rewired the guitar I just used the same wires coming from the pickups. Would it help to wrap each pair of wires in the copper tape?
Also, interesting point about the alternate wiring. I hadn't read anything negative until your post. Now that I've done some further reading, I see why the LP wiring maybe wasn't the most optimal choice.
Thanks again.