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How do I remove a bridge cup to ground a wire on it?

Posted: Sat Jan 18, 2014 2:46 pm
by theshadowofseattle
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Just bought this body. In dismantling my current BTJM, I found that a ground wire snakes through a hole near the high e bridge post cup and presumably grounds to it.

Looking at the pic of the body I got, I think the guy removed this wire. How do I pull the cup out to attach a new ground wire? Can it be done without damage?

Posted: Sat Jan 18, 2014 3:22 pm
by Casual_Reader
if you drop something in the hole and screw in the stud or same threaded bolt, the stud/bolt will pull the bushing up as you slowly screw it in. A little heat from a soldering iron may help.

Posted: Sat Jan 18, 2014 4:54 pm
by George
Casual_Reader wrote:if you drop something in the hole and screw in the stud or same threaded bolt, the stud/bolt will pull the bushing up as you slowly screw it in. A little heat from a soldering iron may help.
really? im pretty sure the cups will have a solid bottom so this wouldn't work, unless i'm missing something here

on my brat i just have a wire coming out the ground of my volume pot that goes out onto the body that way, sort of like a jazz bass. i don't really care about it, but i suppose one day i would look into something more elegant

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Posted: Sat Jan 18, 2014 5:11 pm
by theshadowofseattle
Unacceptable. Nope.

Posted: Sat Jan 18, 2014 6:28 pm
by cur
Have you tried to pry it up with a butter knife under the liP? Use something to act as a fulcrum and to protect the body. It might come out easily. If not, people say to stick a hot soldering iron in the cup for 30 seconds or so or loosen it from any paint or adhesive and then pry with butter knife.

Also, you don't really have to attach the ground wire to the cup. I grounded my jag bridge by stripping about 1 cm of insulation off the grounding wire, and spreading and bending the free wire and threading it out of the cup hole (put kinks in the stripped end so it does not pull out of thimble hole easily). Then just mashed the thimble back in the hole. All you need is a little contact to ground the thing. You can test for conductivity. When the strings are on it will force strong contact.

Posted: Sat Jan 18, 2014 11:12 pm
by DGNR8
As said, I would heat it slightly with a soldering iron and pull with pliers. Other variations include putting something over the body to protect it and angling in a screwdriver or chisel to pry it slightly, to get a better grasp with pliers. To protect the cup you can use tape or cloth or paper etc. to grab it. On occasion where I HAD to remove one for painting that wouldn't budge (because of paint or glue) I have rocked a fat Phillips back and forth to break the seal. This sounds barbaric, but it can be done carefully. Take your time.

Posted: Sat Jan 18, 2014 11:13 pm
by DGNR8
Although hell, where is the science in that? Doesn't metal expand in heat?

Posted: Sat Jan 18, 2014 11:22 pm
by benecol
DGNR8 wrote:Although hell, where is the science in that? Doesn't metal expand in heat?
Aye, I know. Works though; heat that thing up with a soldering iron.

(Just to really mess with our minds, this is also how you fit telecaster string ferrules)

Posted: Sun Jan 19, 2014 12:11 am
by theshadowofseattle
Metal expands in heat, widens the hole, makes the ferrule fit more loosely. Wood also softens in heat because the density is lowered. Makes sense.

Posted: Sun Jan 19, 2014 1:59 am
by cur
The expansion of the cup is negligible in consideration to the drilled wooden hole. What is holding it in place is adhesive in nature - paint, glue, clear coat. You need to soften that. It is not super tight like a metal bushing in metal where you need to put in on dry ice to shrink it a bit to fit. If it was that tight in the wooden hole, the wooden fibers would have been crushed. If that were the case, you could put some dry ice in the cup and it would drop right out.

Posted: Sun Jan 19, 2014 2:31 am
by Casual_Reader
George wrote: really? im pretty sure the cups will have a solid bottom so this wouldn't work, unless i'm missing something here
nope, my bad - I immediately jumped to threaded studs.

heat and pliers - pliers or channel locks without teeth - and / or regular pliers with something (rubber, cloth or leather) to insulate the chrome

or if you're really worried about marring the chrome or finish, what might work are plastic or lead screw anchors - screwing the screw in compresses the liner against the wall for a grip - wiggle and pull screw out with pliers.

the anchors come in packages of whatever, so if you can't find the perfect diameter, you can build it up inside with pieces of a second anchor.

I've seen tools with a cam grip for inside diameters, but even if you could find them, they'd be prohibitively expensive for the purpose.

Posted: Sun Jan 19, 2014 3:06 am
by Awstin
Just take a good set of pliers and squeeze it tight, then pull. It's what i have always done. :roll:

Posted: Sun Jan 19, 2014 2:51 pm
by h8mtv
Ummmmm, why not just ground to the trem?

Posted: Sun Jan 19, 2014 3:17 pm
by Doog
Yeah, my CIJ Jazzmaster is grounded to the tailpiece; helluva lot easier with the same effect.

Posted: Sun Jan 19, 2014 7:12 pm
by theshadowofseattle
Hole is already drilled, seems easier to just use that

Posted: Mon Jan 20, 2014 2:08 pm
by Doog
theshadowofseattle wrote:Hole is already drilled, seems easier to just use that
This thread says otherwise, shadbro

Posted: Thu Jan 23, 2014 7:24 am
by serfx
I thought there was a thread recently on removing those cups.. but I can't find it..

anyways, I usually heat them up a little with the soldiering gun, then use some clamp pliers (or whatever those are actually called) and very gently pull them out.

previously i have taken a small pen knife and pried them up a bit (if say mustang cups that i can't thread a screw in and pull them out that way..) and then again taken clamp pliers..
though the key is to not use much force.. as you can chip the paint, or dent the guitar.. but with the right amount works like a charm, just takes a bit of time and patience.

Posted: Mon Jan 27, 2014 4:01 pm
by theshadowofseattle
It was actually hella easy. Like. Unnervingly easy. Just pinch it with pliers and it pulled up with a gentle tug.

Posted: Mon Jan 27, 2014 5:47 pm
by cur
theshadowofseattle wrote: Just pinch it with pliers and it pulled up with a gentle tug.

Posted: Tue Jan 28, 2014 2:11 pm
by h8mtv
hot