'37 Gibson L-50 repair #3 - Flatback braces

[brewster]

hi, number 3 post on this guitar. the archtop background is in post #1.



the lowest back brace (bass side just below lower F hole eye) on this flatback L-50 is cleanly popped up from the kerfing to the center seam backing strip. see pix. pushing near the outside edge of the brace down with a large flat tip screwdriver takes what i would guess is a moderate amount of pressure. its not floppy.

looking for suggestions please, w/o removing back, on options to get this brace glued back down. there is the old school drill holes and string twist option i'd guess but is there a better way? any cool tools to help do this?

also wondering if just compressing it somehow (how?), at say 2"-2.5" in from the kerfing would be enough to glue the length down or would it need pressure at a couple points (difficult).

advice is much appreciated. brewster

[garybaldy]

Could you manoeuvre a mini jack like this inside? StewMac Brace Repair Jack - StewMac

[Sam Sherry]

That's not an easy repair. One right way is to:
> Remove the brace
> Clean the glue off the brace
> Somehow get in through the f-holes and clean the spot
> Put glue on the brace or on the spot but somehow not anywhere except on the spot
> Use violin or cello soundpost tools to get the brace onto the spot, without spreading the wet glue anywhere except the spot
> Use @GaryBaldy's StewMac jacks, or some sound-posts, to keep the brace in place
> Use soundpost tools to remove the jack or posts
I would pay somebody else to do that every single time!

You can see why some luthiers would prefer to remove the back binding, remove the back, reglue all the braces, glue and cleat any required repairs to the top and sides, reglue the back (resetting the neck angle if necessary), rebind the back and touch up the finish. That way all the braces get 100% down, in the right place and without a bunch of glue goobs.

[nevershouldhavesoldit]

If that brace has been that way for years and it takes a fair amount of force to straighten it out against the back, it's probably warped in that shape and would take a fair amount of force to hold against the back. Even if you can sand the bottom of the brace and the inside of the back down to clean wood without removing the back or the brace, and you use a jack to hold the brace against the back while the glue dries, it probably won't be a lasting repair because the brace will pull itself up as it curls again. There's also the risk that if the rest of the glue and wood is dried out, you could even cause the back (or the top) to lift if you have to apply a lot of force force with a jack.

I suspect that the only way to get a durable repair is to expose and remove the brace by removing the back. Reshape it with steam etc (or make a new one) so it fits like it did when the guitar was made, before gluing it back in. Anything short of that wil probably be a temporary repair. It could last a few years, but my bet is that it will end up just like it is now if you don't straighten or replace the brace.