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Hey folks,

I had a customer drop off a guitar to have the endpin jack fiddled with, and I noticed he has a cracked bridge. It looks to me like the saddle is too high and the string tension put too much forward pressure on the saddle. I assume this is caused by the under saddle pickup, but the customer tells me it came pre-installed and I would have thought Martin would have addresses an issue like that. The customer, apparently, had not known of the crack and would like it fixed.

In your opinions, is this a crack that can be glued and clamped in some way, or is this a case of bridge replacement?


Thanks,

Dustin

Looks like it cracked right along that dark grain line. It hasn't opened up so I'd guess its stable underneath. I think the glue would hold it together ok
Can you lower the saddle some or is the action already ok?

Looks like the run out on that grain is awful, I would not have made a bridge from that piece of wood. Glue should hold, at least it's worth a shot.

_________________
Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Thanks for the input.

The customer has no problems with the action and it looks and feels ok to me, so I'll leave the saddle height alone.

If I were to try and glue it, what type of glue should I use? My instincts (which still need a lot of honing, which is why I ask these questions) would be to use CA. Also, that seems like a tough spot to get any clamping pressure. Are there any tricks I could use to get that clamped?

Dustin, it looks to me like the grain direction also happens to be parallel to the routed saddle slot. And the grain ran out, as Brian says, right where the bridge slopes down to the treble side foot. It's as if the saddle is trying to split the grain line like a froe. I don't know whether this is inherently a weak orientation, or if it's just one of those things that happens sometimes. I do agree that CA glue (thinnest viscosity) wicked into the crack would probably hold, and it's certainly worth a try for now. You can replace the bridge later, if it becomes necessary.

Remove the strings and pins and see if the crack closes by itself. If so, it should be a relatively easy repair.
I think some light pressure with a bridge clamp is all you need. If the crack wants to close tightly, you might even get away with some protective tape and a fairly light weight resting on the bridge for an hour or so.

If the crack doesn't close on its own, then I'd try a spring clamp front to back coupled with a bridge clamp or deep throat c-clamp to apply downward pressure. Light pressure and cauls will be essential. I'd wax any part of the cauls that might touch CA glue. Or I'd put wax paper under the cauls.

You can probably find a lot of discussion and repair advice on cracked bridges in the archives here. I'm sure many people have repaired very similar problems. My comments are just suggestions. If seasoned repair people disagree, listen to them first! Good luck with it and let us know how it goes.

Further investigation tells me that this bridge isn't actually wood!! According to Martin, this bridge is made out of Black Richlite, which appears to be a paper composite made from pulp and resin.

How might that affect my choice of glue and/or gluing methods?

naw thats gotta be wood. i think the richlite looks like ebony(at a glance)...solid dark black/brown color, no pores, no grain, fake or otherwise.....

I thing HHG or fish glue would be a good choice as it makes for the best invisible glue line. But CA would work. CA might be best if it's hard to clamp since you can clamp with finger pressure.

Good lesson on why flat sawn is a good choice for bridge.

When the techies at Martin gave you that answer, they couldn't possibly have been looking at this photo. I'm convinced the bridge in your pictures is wood. As to which particular species, I couldn't say. Treat it as wood. Or....just go ahead and buy a rosewood bridge blank and fashion a new bridge and replace the thing, and have it done.

I got the info from the Martin website. But, you're right, based on the photo, that's got to be wood.

I appreciate all the input. If the customer chooses to have it fixed, I'll let you know how it turns out.

i never even considered this, although it seems obvious....