Bridge Out!! Questions

If you have a string instrument of any kind that needs fixing, a mistake you made in building a new instrument that you need to "disappear," or a question about the ethics of altering an older instrument, ask here. Please note that it will be much easier for us to help you decide on the best repair method if you post some pictures of the problem.

Bridge Out!! Questions

Postby Gordon Bellerose » Tue Nov 06, 2018 12:34 am

One of my customers brought in an electric guitar that had some "bridge issues".
The posts have moved forward under string pressure, and one of them actually pulled out.
I have attached a couple of pics to help explain.

You can see that the wood in between the bridge and the bridge pickup has cracked all the way through, and moved forward slightly.
The holes are oblonged.
Bridge Out 1.jpg


The other side is not quite as bad, but still cracked all the way through.
Bridge Out 2.jpg


First a bit of background.
The guitar is a Parker Fly. It has a vibrato bridge very similar to a Strat.
The bridge is equipped with piezo saddles that seem to be run through the bridge plate, and then run through one thin wire to the control cavity. The wiring seems to be "glued" or "coated" onto the underside of the bridge plate. I'm not sure how that system works. I will post a couple pics of it in my next post, so you can have a look also.

I do not want to lose the piezo capacity, even though the owner doesn't really care. He says it's ok to put a different bridge on the guitar if necessary. He does not use the vibrato, so it's ok to lose that too.

My thoughts are to cut the broken piece out and replace it with new wood. I would even fill the spring cavity with new wood, and fill in behind the trem block also, to stabilize the bridge in one position. That way, I could drill new mounting holes and screw the bridge plate down, leaving room for the piezo wiring.

My questions are these: What in your opinion is the best way to proceed? Do you think my method will work, or is there an easier better way?
I need your help. I can't possibly make all the mistakes myself!
Gordon Bellerose
 
Posts: 1093
Joined: Wed May 30, 2012 11:47 pm
Location: Edmonton AB. Canada

Re: Bridge Out!! Questions

Postby Peter Wilcox » Tue Nov 06, 2018 2:02 am

I assume there is a crack/split along the bottom of the pickup cavity, and one in the trem block cavity also. Can you knock that piece of wood back into position? If so, maybe wick some CA along all the cracks to keep it there. That would seem to be the simplest solution. However, I'm not familiar with this guitar, and probably don't understand the extent of the problem.
Maybe I can't fix it, but I can fix it so no one can fix it
User avatar
Peter Wilcox
 
Posts: 968
Joined: Sun Jan 08, 2012 1:31 am
Location: Northeastern California

Re: Bridge Out!! Questions

Postby Joshua Levin-Epstein » Tue Nov 06, 2018 5:02 am

http://fingerlakesguitarrepair.com/fend ... trem-stud/

Gordon, I remembered a similar repair posted.
Joshua Levin-Epstein
 
Posts: 206
Joined: Sun Jan 08, 2012 7:58 am
Location: Massachusetts

Re: Bridge Out!! Questions

Postby Barry Daniels » Tue Nov 06, 2018 10:33 am

I have seen this several times before. There is just not enough wood there to support the posts.

If you can put in new wood and maximize the contact with the body then you have a better chance of success. I would use hard maple for the patch to provide support for the posts. And I would taper the sides of the patch to minimize the chance of future slippage.
MIMF Staff
Barry Daniels
 
Posts: 2002
Joined: Thu Jan 05, 2012 10:58 am
Location: The Woodlands, Texas

Re: Bridge Out!! Questions

Postby Gordon Bellerose » Wed Nov 07, 2018 3:24 pm

Thanks guys.
I think in light of the fact that the owner doesn't use or want the tremelo function, I will fill the spring cavity, and the trem block cavity with new wood, including cutting out the broken piece.
I can even remove the trem block and drill new holes in the bridge behind and under the saddles to attach to new wood farther back.
This only leaves the question of drilling new string through holes and inserting ferrulles.
The back of the guitar is pretty much covered by a large cavity cover, so this wouldn't even be seen.
I guess the next question is if the owner wants to pay for all that!
I need your help. I can't possibly make all the mistakes myself!
Gordon Bellerose
 
Posts: 1093
Joined: Wed May 30, 2012 11:47 pm
Location: Edmonton AB. Canada

Re: Bridge Out!! Questions

Postby Gordon Bellerose » Mon Nov 12, 2018 11:11 pm

I'm still thinking about this repair.
I believe Barry has the simplest solution.i will cut out the broken piece on a taper, and replace with good hard maple.
After that I think I might drill 4 new holes and use 6 screws to re-attach the bridge.
That will spread the forces of the bridge across the whole width.
I need your help. I can't possibly make all the mistakes myself!
Gordon Bellerose
 
Posts: 1093
Joined: Wed May 30, 2012 11:47 pm
Location: Edmonton AB. Canada

Re: Bridge Out!! Questions

Postby Gordon Bellerose » Mon Nov 12, 2018 11:40 pm

Here are the pics of the bridge wiring. What can anyone tell me about this type of wiring?


1. Wires under Saddles.
Under Saddle Wires.jpg


2. Wire Coating? on Bottom
Bridge Wiring Underneath.jpg


3. Wire Continues out rear of Trem Block
Bridge Wire in Rear Bottom.jpg
I need your help. I can't possibly make all the mistakes myself!
Gordon Bellerose
 
Posts: 1093
Joined: Wed May 30, 2012 11:47 pm
Location: Edmonton AB. Canada

Re: Bridge Out!! Questions

Postby Peter Wilcox » Tue Nov 13, 2018 2:14 am

Apparently each saddle has an internal piezo crystal. These are connected via each wire to the strip under the bridge. There is a coaxial wire from this strip to the control cavity carrying the signal from the piezos on a central wire, covered by a grounded shield.

There's a schematic here which might help: http://forums.parkerguitars.com/index.php?topic=4116.0
Maybe I can't fix it, but I can fix it so no one can fix it
User avatar
Peter Wilcox
 
Posts: 968
Joined: Sun Jan 08, 2012 1:31 am
Location: Northeastern California


Return to String Instrument Repair: Practical and Political Issues

Who is online

Users browsing this forum: No registered users and 2 guests

Your purchase from these sites helps support the MIMForum, but only if you start at the links below!!!
Amazon music     Amazon books     Amazon tools     Rockler tools     Office Depot    

The MIMF is a member-supported forum, please consider supporting us with a donation, thanks!
 • Book store • Tool store • Links •