Official Luthiers Forum!

I acquired a 76 Gibson J45/50 project guitar and it is rather needy. The guitar is one of many in my project pile, so I'm in no particular hurry to get it done. I have the luxury of time, so I have been poking around for someone with access to a J-45/50 that can measure and report their unmolested, original bridge thickness. I have searched Google and also have the same question posed over at; Frets, MIMF and UMGF forums and have also emailed and gotten an "I don't know" response from Gibson. It was suggested that I also try here, so hoping someone in this community can fill in the blank for me.

At some point a previous owner decided to thin the bridge, now 3/16" thick, rather than have the needed neck re-set work done (the action is still way high). I already know that many Gibson flat tops with drop in saddle bridges range from 1/4" to 5/16" or more thick. My plan B, if I don't get a definitive response will be to make a new bridge 5/16" thick and then re-set the neck to that height. Since I am in no hurry, my plan A is to discover what the original stock thickness would be for this model and restore the instrument to original specs. Hoping someone can help.

Paul

Reso, this isn't a whole lot of help but its the best I can do. I don't happen to have a 76 J45 but I have the Collins plans for a '57. He shows three bridges, a rectangular one and two reverse belly bridges. He does not call out the thickness but measuring the one side view I get right at 0.250.

I also have a '50's LG0 on my bench right now with the standard plastic reverse belly bridge - it measures 0.267.

A few years ago I replaced the plastic reverse belly bridge on an LG-1 with an aftermarket one that I bought somewhere (big help aren't I?). When I look at pictures of that repair the bridge doesn't look all that thick - I'm going to guess close to a quarter of an inch. I know I did not have to reset the neck to the bridge and it has a nice tall saddle.

Last, and somewhat confusing, I have a reverse belly bridge that I bought from LMII for a possible J45 build - it measures 0.351 thick.

Thanks Freeman for taking the time to post this stuff.

The problem is Gibson has been all over the map with their builds through the years. Various models have been changed up frequently with little or no documentation. Workable bridge thicknesses will land somewhere between 1/4" and 3/8", I'll likely settle on 5/16" but was hoping someone could document what was used on the same model and year guitar.

I've got a source for a '74 J45 and have asked him if he would measure it.

Each bridge/neck pair has its own unique relationship, evolved as time (and the settling of the guitar body) passed. Whatever a bridge height might have been when the instrument was new could very well be irrelevant today. And in any case, is valid on one particular instrument, and OP doesn't have that instrument. I suggest OP make a bridge that suits the guitar in front of him, after verifying the validity of the neck set on that particular guitar.

_________________
Peter Havriluk