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Chads bridge question doubled
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Author:  Bailey [ Tue May 11, 2010 9:01 am ]
Post subject:  Chads bridge question doubled

Found 2 of my previous OMs have a bridge issue. Both are lifting at the rear end corner. One on the treble and the other one on the base side. Everything looks secure except for the corner lift where the outer corner is pulling (with tension) up about 1/64 and seems to stop in about 3/4 in. Is it worth attempting to get glue in the lifted area and reclamp? I'll probably have to string up on that side of the bridge to put tension on...fill the area with glue..... destring and clamp to achieve this........ My guess is (I know the answer) the consensus will be pop'm off.
I removed a bridge on a 46 year old classical last year with a little heat from the cloths iron and a block and hammer whack. The guitar was trashed....so it didn't matter what happened to the top...I just wanted the bridge to use on a new top. Removing a bridge on 2 branny new guitars is quite another thing. Any suggestions?
I used luthier white glue on both of these bridges ( the glue didn't look or act or smell bad....but I tossed it this morning) I think I'll use titebond when I reglue.
Kent

Author:  jackwilliams [ Tue May 11, 2010 9:41 am ]
Post subject:  Re: Chads bridge question doubled

Kent,
I would be very surprised if it would be possible to re-glue the corners of the bridge ; probably best to remove and re-glue.

You may already be doing this, but the bottom of the bridge needs to be fitted to the top of the guitar... you probably already know the drill..120 grit taped the the top around the bridge area, and sand the bottom to conform to the top
I would suggest also the use of hot hide glue, or fish glue to re-glue.
regards,
jack

Author:  Bailey [ Tue May 11, 2010 10:44 am ]
Post subject:  Re: Chads bridge question doubled

Yes....I did my curve to fit the top using the old sandpaper on the guitar top to achieve the same curve.....surface was perfect for glue. I attempted to utilize all the forum info. and literature to attach these bridges correctly. I thought I had done a good job. Whatever I did wrong....I did it on both SS.
I'll pop'm off and do it again. Hopefully, I don't ruin a top doing it.

I'm a sickened old man ....
Kent

Author:  Daniel Minard [ Tue May 11, 2010 11:29 am ]
Post subject:  Re: Chads bridge question doubled

I have had trouble with lifting bridges in the past (I hope!). Some of them started lifting at the back edge of the wings, as you describe. Discouraging, to say the least. I even resorted to using epoxy on a couple of instruments!
I agree... you should remove the bridge and start again.
Here's what I did to get around the problem.
1) I made a domed sanding block (A simple job, needing only a good, stable piece of hardwood & your sanding dish) & glued the paper to it instead of taping paper to the top.
I find it makes for a more accurate fit. With sandpaper taped to the guitar top, I could never get the wings to contact perfectly. To check the fit, lay the bridge on the top, gently holding down one wingtip. Then tap the other wingtip with a finger. If there is ANY movement, you're not there yet. I do this part before I remove the finish. (This only works if you don't have masking tape under the finish. See # 5.)
2) More glue. I used to try for very small amount of squeeze out. Now I liberally coat both surfaces & clean up the mess afterwards.
3) More clamps! I use a minimum of four clamps... More, if I can get 'em to fit. (I use the Stew-Mac bridge clamps - they work great)
4) Simplified the shape of my bridges. I used to make "points" on the back edge of the bridge. A smooth line makes for easier finish removal & a better fit. (And eliminates a possible stress riser)
5) I stopped using tape to mask under the finish, on the off chance that the tape was leaving glue residue in the joint.
6) Carefully scrape (not sand) the bridge immediately before applying the glue. Just enough to remove the sandpaper scratches.
These steps seem to have solved the problem... Won't know for sure for a few years, I guess.

Author:  Bailey [ Tue May 11, 2010 1:26 pm ]
Post subject:  Re: Chads bridge question doubled

Daniel, thanks for taking the time to reply with such a lengthy detail
Kent

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