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  #1  
Old 04-06-2020, 10:09 PM
tadol tadol is offline
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Default Anyone know what this “repair” might be?

I’m having trouble with the pickup in this guitar - getting static and crackling noises from it - so I stuck my mirror in there to se what it was, and it seems to be an old LB6, so I figure I’ll just have to replace it. But this brown strip has me confused - it seems like a glue job, possibly to cover up some bridge plate damage?, but it covers only 5 strings, and extends over to where the pickup wire extends, and it seems like it is not well adhered -

I haven’t pulled the strings and gotten in there yet, but thought I’d ask if anyone’s seen anything like this? Thoughts about removing, or ??

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Old 04-07-2020, 12:32 AM
tadol tadol is offline
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Ignore - I went ahead and pulled the strings to try and repair this, and discovered that it was a copper shield that had been glued onto the bridge plate, possibly with some kind of contact cement, that was failing and parts of the copper had peeled up. I’ve just gone ahead and removed everything, and will just make a new saddle while I wait to get my new Ultratonic pickups -
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Old 04-07-2020, 06:53 AM
packocrayons packocrayons is offline
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Was the copper shield connected to anything? It's common in electrics to ground the strings, so that the big bag of water playing it acts as an (electrical) noise sink. Perhaps the pickup was noisy, and an electric guitar tech tried grounding the strings to reduce noise. Why one string was left out, I can't say.
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Old 04-07-2020, 01:05 PM
Th'Axe Th'Axe is offline
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Default LOL

"big bag of water" playing it. Thanks, I needed a good grin this AM. Substitute appropriate terminology regarding container and substance?
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Old 04-07-2020, 04:37 PM
tadol tadol is offline
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Quote:
Originally Posted by packocrayons View Post
Was the copper shield connected to anything? It's common in electrics to ground the strings, so that the big bag of water playing it acts as an (electrical) noise sink. Perhaps the pickup was noisy, and an electric guitar tech tried grounding the strings to reduce noise. Why one string was left out, I can't say.
No - not attached to anything inside the guitar - I thought maybe it was to try and ground the strings to each other, but does that do any good if not wired to earth?

It was clearly an after-attempt to try and resolve the problem with the pickup - I originally thought the while thing might have been installed that way, but after removing it all I realized every other aspect of the install was incredibly clean and accurate - unscrewed the battery clip from the neck-block, and saw it was attached to a carefully cut block of ebony that had been glued onto the neck block. As soon as I saw that, I was pretty sure this was a factory install done at SCGC back in ‘94, and they would never have done such a poor job of applying the copper shield. I’ve seen a couple other Santa Cruz’s that have had ebony blocks installed on the neck block, probably to prevent the screws from potentially interfering with the dovetail - but one with the original owners initials inlayed in MOP -

This is the second of these pickups I’ve had to remove - I’m beginning to wonder if they only have a 20-30 year working life -
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  #6  
Old 04-08-2020, 06:13 AM
packocrayons packocrayons is offline
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Quote:
Originally Posted by tadol View Post
No - not attached to anything inside the guitar - I thought maybe it was to try and ground the strings to each other, but does that do any good if not wired to earth?

It was clearly an after-attempt to try and resolve the problem with the pickup - I originally thought the while thing might have been installed that way, but after removing it all I realized every other aspect of the install was incredibly clean and accurate - unscrewed the battery clip from the neck-block, and saw it was attached to a carefully cut block of ebony that had been glued onto the neck block. As soon as I saw that, I was pretty sure this was a factory install done at SCGC back in ‘94, and they would never have done such a poor job of applying the copper shield. I’ve seen a couple other Santa Cruz’s that have had ebony blocks installed on the neck block, probably to prevent the screws from potentially interfering with the dovetail - but one with the original owners initials inlayed in MOP -

This is the second of these pickups I’ve had to remove - I’m beginning to wonder if they only have a 20-30 year working life -
Just connecting them to each other won't do much except reduce cross-talk, however we're getting into rf engineering here. You guys also play inside a faraday cage, right? You've got me stumped as to why that foil would be there - I'm questioning what person would even have copper foil laying around, it's not exactly a common material to have around the house.

My first thought on life would be piezo fatigue, but it doesn't seem like that would be the case (piezo crystals last into the trillions of cycles). It's possible they just aren't built quite right.
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