Bridge Problem

[harald_rost]

Hello, when I opened the door to my music room yesterday I had a bad surprise. The strings were hanging down on my 1976 Series 1 and the bridge was on the floor. The only explanation in my opinion is that the neck had moved and pulled out the bridge from the wood. As you can see in the pics the screws are broken. Probably the movement of the neck was caused by the heating of our house which we started some days ago. So what to do? How to put the rest of the screws out of the wood to get new screws in? Drilling new holes? How long should the new scres be without damaging any elecrtonic? Any advice is highly appreciated.  Harald from Germany (I hope my english is correct)

 

  (Message edited by davehouck on October 04, 2009)

[pauldo]

Harald - dare I say that is a catastrophic failure. I could give advice but feel that the Mothership should be involved with this one.
 
I certainly hope that Mica can offer you the best solution to repairing this.
 
good luck

[811952]

I seem recall at some point several years back that Mica or Susan was recommending replacing the original bridge screws with stainless steel or something like that, for this reason.  Of course, I haven't done so, but maybe now I will..
 
Brass screws are relatively soft, so it should be possible to drill them and use an easy-out (reverse-threaded screw) to remove them.  I would check with a machinist about it.
 
John

[jazzyvee]

Wow that is some failure.  Looking at the length of the screws i would have expected more wood damage as they were levered out of their holes. Thankfully not. I'm sure Alembic could fix this no problem. It would be interesting to find out what caused it.

[David Houck]

You should get Mica's input.  I'll move this thread to the Troubleshooting section where she will be more likely to see it sooner.

[afrobeat_fool]

Did you buy this new? It looks as if there is epoxy on the screw threads, and the bottom of the tailpiece. If you did not buy it new I think someone tried to repair it in the past.

[keith_h]

To start with you will need to use an easy out or similar device to remove the remaining parts of the screws from the body. This is not for the faint of heart as it requires drilling a hole in the middle of the screw stuck in the body. After removing the screw I would use threaded inserts to fasten the tail piece. My suggestion is you refer this repair to your luthier. This what I would do if the bass belonged to me.
 
Keith

[David Houck]

As for how this happened, maybe I'm not thinking this through right, but it seems to me that when heating up your house, you're removing moisture from the air, reducing humidity, which means there should be more relief in the neck and thus less tension on the strings instead of more.  Thus, I don't think heating the house would have caused this.  But then I don't know what would have caused it either.

[811952]

There is an old thread on this somewhere..  I think the issue is that the screws get more torque during installation than they, being soft brass, like..  Failure may not happen for years from stress fractures administered at, er, birth of the instrument, for lack of a better term...
 
John

[David Houck]

John, that seems to make sense; much more so than my theory, which is that someone broke into the house in the middle of the night and yanked on the strings really violently, and then quietly sneaked back out of the house.
 
Harald, I think you should get Mica's opinion before you do anything; but Keith's suggestion sounds like a good plan.

[811952]

As long as they weren't leprechauns, then your theory is entirely viable.  I believe leprechauns would have also chewed up the headstock.
 
John

[artswork99]

Of course Mica's input is always valued in any situation...  
 
Screw extraction is a delicate operation as Keith indicated.  If you attempt this on your own be sure to use a center punch tool to make a definitive starting point to help the drill bit from sliding off center.  It's really not that hard if all the correct tools are used. If you get the old screws out clean and the lack of initial damage to the wood (a really good thing), you could possibly get away with only a replacement screw though I would probably start with a minor wood plug to give you added strength in the area when remounted.
 
Is that a type of glue in the picture under the bridge?

[811952]

It looks like a walnut veneer to me.  I would guess maybe to provide a sacrificial layer should the tailpiece adhere to the body/finish?
 
John

[artswork99]

John that does look like a veneer.  Maybe a very thin layer of clear silicone which still appears in several of the string slots, around the screws and a small ball of it in the last few pictures??
 
(Message edited by artswork99 on October 04, 2009)

[harald_rost]

Thanks for moving this thread to the right place Dave and thank you all for the advices.  
 
I bought this bass in 1999 from a bass player from Austin so I don't know his history before. It seems like there is some kind of silicon under the tailpiece - for what reason ever. May be to assist the screws holding the tailpiece. Yes, maybe there was a similar problem in the past with that.
 
Of course I will wait if there is an input from the mothership to fix this, may be Mica will read this thread or I will send an E-Mail. I'm not sure if I can get out the rest of the screws properly so I will look for an luthier here in this area. Also I'm not sure about the best way for a solution that this doesn't happen anymore. I'm glad there was no more wood damage.
 
A lot of luthiers settled down in this area where I live after second world war and the factory of Hoefner is not far away. Also here was the beginning of Framus where Warwick later came out from. I think there are still some small guitar builders in this area I have to look for.  
 
So many responses in some hours, this is a great community.
 
Harald