Strat Wiring Issue

[MrBump]

Guys, this is driving me mad.  I've rewired loads of guitars, and have rarely had any issues installing pickups.

Generic strat build, 3SCs, normal 5 way switch, one vol, two tone controls.  Bog standard.

No sound.  First time around, I didn't use a multimeter, so I just removed everything and started again (I had spares of everything, so swapped out all components).

Still no sound...

So no the multimeter, and rambling question.

Continuity is good at all points from the 5 way switch hot lug all the way to the lead (plugged in to the jack).  However, there's continuity from the hot to the earth (sleeve) of the lead - that's bad, right?  That means that somewhere in the wiring I've managed to make a connection to earth in the hot bit of the circuit?

[darkbluemurder]

However, there's continuity from the hot to the earth (sleeve) of the lead - that's bad, right?  That means that somewhere in the wiring I've managed to make a connection to earth in the hot bit of the circuit?

Yes - you have a short to ground somewhere in your wiring. If there is no visible evidence - such as a solder bridge between two pins (of a switch or volume control) that should not be there or a wire isolation that has come off, do the following:

1. Desolder the wire from the switch to the volume pot and measure again between hot and earth/ground. If you still have continuity then the short must be between the volume pot and the output jack. If you now have an open circuit, the short is in the wiring at or before the switch. That will help you to isolate the problem.

2. Continue the isolation process until you find it.

3. Always keep in mind that whenever an electronic circuit is not working as expected there is a valid reason. It's just a matter of finding it.

Good luck,
Stephan

[Dave Sloven]

Any shielding paint near the jack?

If so maybe grind some away or put electrical tape between the paint and the jack hot.

[MrBump]

Cheers, guys.

Any shielding paint near the jack?

If so maybe grind some away or put electrical tape between the paint and the jack hot.

Yes, I think that it might be the copper sticky shielding that I've used in the cavity - I think I'm probably making some sort of earth connection to live from that.  PITA though, because I've done it twice now with the same issue!!!

I'm going to start again, checking DC resistance at the lead each time I make a new connection, I think...

[Dave Sloven]

If you put black electrical tape over the shielding the shielding will still work without causing a sort.

If it is only the jack hot that is causing the issue you might be able to remove some shielding there.

I made that mistake with my Explorer.  I got shielding paint into the jack tunnel.  There wasn't enough clearance for tape so I had to sand the paint away (wearing a mask).  If it is copper tape hopefully you can just peel it away near the jack.

If you think it might be the pickups shorting against the bottom of the cavity just cover the bottom of the cavity with electrical tape. I had this issue with my Jazz bass when I upgraded the shielding, but a layer of tape and all was well.  The shield is just under the tape, it doesn't affect the shield.

I thought this might happen to my friend's Telecaster when I shielded his cavities and installed a SD Quarter Pound pickup; I just lined the bottom of the cavity with black tape and all was well.

[MrBump]

If you put black electrical tape over the shielding the shielding will still work without causing a sort.

If it is only the jack hot that is causing the issue you might be able to remove some shielding there.

I made that mistake with my Explorer.  I got shielding paint into the jack tunnel.  There wasn't enough clearance for tape so I had to sand the paint away (wearing a mask).  If it is copper tape hopefully you can just peel it away near the jack.

If you think it might be the pickups shorting against the bottom of the cavity just cover the bottom of the cavity with electrical tape. I had this issue with my Jazz bass when I upgraded the shielding, but a layer of tape and all was well.  The shield is just under the tape, it doesn't affect the shield.

I thought this might happen to my friend's Telecaster when I shielded his cavities and installed a SD Quarter Pound pickup; I just lined the bottom of the cavity with black tape and all was well.

Good call - I've stripped it all out this morning, and I think I'll tape over the top of the copper before rewiring.

[darkbluemurder]

I would not shield a guitar with humbuckers. It's simply not necessary.

For single coil equipped guitars it can be beneficial in reducing the hum but putting in humcancelling ones would cancel the hum much more effectivly than any shielding measure.

In addition, I found shielding adversely affects tone, at least when copper tape is used. I noticed that when I ripped out the copper tape I used to shield the cavity of one of my teles (this one has rails pickups from a different manufacturer). The high end in both pickups got bigger and much less stiff in feel. 

Cheers Stephan

[MrBump]

Woo-Hoo!

Top tip re the shielding - it was that.  The volume pot was earthing against some of the copper shielding and shorting it.  I removed all the pots and insulated around them before mounting again.

Works like a fecking charm!!!

Thanks guys.

[Dave Sloven]

Good to hear it!