bridge repair

robert(original) · Post by **robert(original)** » Mon Nov 30, 2009 3:21 am

pretty much everyone here has had or has known someone with an acoustic guitar that the bridge has started to lift off.
i have done this before but it was before the site went ape shit and we lost everything.
so here it goes again.
this is a kay guitar that my buddy in milwaukee needs repaired, apparently it has some family history and means alot to them.
this is the bridge.

as you can tell it came stock with two screws to help hold it down(common practice) and the bridge saddle itself is an ajustable type.
this is the "lift" from the voice of the top(ITS A SOLID TOP!!!)

i first removed both of the screws by taking off the inlay fots and unscrewing them. then i got out my iron and with a wet towell i began to steam off the bridge.

it only took about 5 minutes to get it off.

once its removed i clean up the glue area of the guitar and the bridge saddle itself.
and around this time i can accurately measure the lift of the top and what i will have to do for it.
this one lifted ALOT more than normal, a full 1/4 inch!

so my next step is to try and reverse about 40 years of warp by flatting the top with steam and pressure.

it was around this time that i started to check the bracing. the top bracing was great! but the bottom.... not so much. im going to have re-glue all the back bracing.

its still in this state, but tomorrow after work i should be able to start on the bits to re-glue the back bracing. i tried to explain to sloan how i did this but i think i lost him in the explanation, so i shall go into great detail tomorrow.

cobascis · Post by **cobascis** » Mon Nov 30, 2009 3:24 am

Awesome post. It's sort of shocking the bridges are just held on by glue, no?

James · Post by **James** » Mon Nov 30, 2009 3:31 am

What would you expect them to be held on by? Magic and hope?

robert(original) · Post by **robert(original)** » Mon Nov 30, 2009 3:36 am

a good glue line is stronger than wood itself. don't believe me? i repaired an alvarev acoustic neck about 3 months ago, well, it broke again, but not on my glue line, but rather the weak points of the wood.
basically from the 50's-80's ALOT of companies used these lil screws to help with the glue line.
also i should mention that becuz the bridge is ebonized maple rather than rosewood it doesn't flex with the top like most do.
so in a way, a softer wood acts like a top brace, as opposed to a harder wood doesn't do as much good and comes unglued.
especially when you are a jap comp in the 60s and you used jizz and spit to keep your guitars together.

cobascis · Post by **cobascis** » Mon Nov 30, 2009 3:44 am

James wrote:What would you expect them to be held on by? Magic and hope?

I just picture some failed art projects from like 3rd grade when I think of glue. I used wood glue today on my cab. It's just that there is so much tension at the bridge. robog, thats crazy that it is stronger than wood in some cases.

robert(original) · Post by **robert(original)** » Mon Nov 30, 2009 3:55 am

these pics kinda suck, but you get the general idea.
basically, it fell off of a stand and broke at the weakest point, also known as "gibson syndrome!"

I glued it usingf titbound and then coated it with epoxy.
about 3 months later it was in the case when the case took a hard dive to the floor and it broke again.

as you can tell the og break is still glued nicely, and the new crack is right above the old one, proving that my glue line is stronger than the wood itself.
my teacher in st. lious taught me about this basically saying that with wood glue, less is more and glue does not bond to glue, it merely bonds to things together.

the last pic is a bit of a teaser, im going to do a "how to" on re-glueing with a dowell rod" sort of thing, but i have about 6 repairs(high dollar stuff) plus about 2 full customs, along with trying to move all my shit into a penske van.
btw, anyone wanna help me load a van?

cobascis · Post by **cobascis** » Mon Nov 30, 2009 4:03 am

robert(original) wrote:

these pics kinda suck, but you get the general idea.
basically, it fell off of a stand and broke at the weakest point, also known as "gibson syndrome!"
I glued it usingf titbound and then coated it with epoxy.
about 3 months later it was in the case when the case took a hard dive to the floor and it broke again.
as you can tell the og break is still glued nicely, and the new crack is right above the old one, proving that my glue line is stronger than the wood itself.
my teacher in st. lious taught me about this basically saying that with wood glue, less is more and glue does not bond to glue, it merely bonds to things together.
the last pic is a bit of a teaser, im going to do a "how to" on re-glueing with a dowell rod" sort of thing, but i have about 6 repairs(high dollar stuff) plus about 2 full customs, along with trying to move all my shit into a penske van.
btw, anyone wanna help me load a van?

Wow. Interesting, epecially about the less is more in terms of wood glue.

finboy · Post by **finboy** » Mon Nov 30, 2009 5:27 am

my old 12 string is slowly prying the bridge off of the sound board and turning it into an arch-top. i figure when it finally goes i'll just spend the extra cash and have something besides plywood put on the top.

filtercap · Post by **filtercap** » Mon Nov 30, 2009 5:37 am

Reminds me of when a friend's 12-string acoustic unbridged itself while I was holding it.

Me:

Guitar: BLAM
Me:

He always bought cheap stuff. That guitar was a time bomb.

finboy · Post by **finboy** » Mon Nov 30, 2009 5:48 am

to bad you didn't pete townhsend windmill the thing while it happend.

BRING THE ROCK WITH ALL 12 STRINGS

filtercap · Post by **filtercap** » Mon Nov 30, 2009 5:56 am

finboy wrote:to bad you didn't pete townhsend windmill the thing while it happend.

Given the way he made me pay for the repair, he must have thought I was. No rocks were brought, it just went to pieces.

robert(original) · Post by **robert(original)** » Mon Nov 30, 2009 8:09 pm

if the bridge is starting to come up already you are better off taking it off right now and re-glueing it.
every acoustic guitar gets a "voice" after about 6 months-2 years depending on the wood and bracing style, this voice(behind the bridge, its a "bump") gives the guitar about half of its overal sound and vibration. and have the bridge properly glued on is a must, if its half on, half off then you are losing volume and "tone"
plus it will pull the wood in a direction that it doesn't want to go, i.e. down towards the neck and up towards the butt.

DGNR8 · Post by **DGNR8** » Tue Dec 01, 2009 3:22 am

You go, Robert!

I bought a cheap acoustic on Reranch (a 1930s Kalamazoo) that the bridge had come off of. I bought some hide glue in a standard bottle and it worked great. Uh, but I can't get it to intonate properly, so I am going to heat and remove it again. I think I got the ebony too high, and now that I have seen what a belt sander can do, I will be able to sand it down more easily than BY HAND. The fear is gone.

robert(original) · Post by **robert(original)** » Sat Dec 05, 2009 9:10 pm

hellz yeah dgner8, manland style!
i got some newer pics.
i got the bridge cleaned up and the bridge area cleaned up about half of the way.
did a dry glue and it looks like everything will work out just fine, and in the mean time i made about 5 of these lil latter looking things to re-glue the back bracing on the inside of the guitar.

robert(original) · Post by **robert(original)** » Tue Dec 15, 2009 5:05 pm

the bridge has been glued and clamped for about 40 hours now(its cold and wet in the shop atm)
and here is a hole i drilled about 3-1/2 inches in and dowelled it and used wood epoxy.

Sidney Vicious · Post by **Sidney Vicious** » Tue Dec 15, 2009 5:49 pm

Great work - thanks for taking the time to document and post the bridge repair process. Very good of you to share your knowledge.