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'Standard' bridge plates seem to be a maple slab, grain running the long way. I have some carbon fiber mat I could use, the c/f being between the bridge plate and the soundboard. The composite bridge plate would need to be epoxied into place. Any advantage to this? Or make up a wood + cf mat + wood 3-layer bridge plate as thick as a straight maple one, glued on with Titebond.

Thoughts, reactions, warnings?

Thanks!

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Peter Havriluk

Per Gore’s book I did a wood/CF/wood sandwich for the bridge on a falcate braced guitar and it worked well. Only issue was when I tossed the bridge in the microwave to warm it up before I glued it on with HHG -ha! Not a good idea with CF. Otherwise no problems with it. Don't imagine it would be any different with a bridge plate.

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Steve Smith
"Music is what feelings sound like"

Now I need a microwave in my shop. Does it ever end? I know the answer.

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Hutch

Get the heck off the couch and go build a guitar!!!!

I don't think I like the idea of epoxying the carbon fiber and bridge plate to the soundboard. Seems like it would make bridge plate replacement difficult. I suppose you could argue that a bridge plate with CF would never need to be replaced. I think it would be better to put thin wood between the spruce and CF.. I'm thinking a wood/CF/wood veneer laminated bridge plate all attached to the spruce with HHG or titebond.

Just thinking out loud.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Hey Hutch, go down to the Goodwill store and you can probably find a small microwave for almost nothing. I mostly use mine to heat water for the hide glue pot or for glue cleanup. Just makes things faster.

And you're right, it never ends.

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Steve Smith
"Music is what feelings sound like"

I have used Trevor Gore's design on a number of guitars and it has worked very well - ie a wood/ CF sandwich bridge and a bridge plate with CF against the top, glued with epoxy.

However you need to remember that this is all part of his particular bracing system - often Falcate. The bridge itself is often smaller than a traditional one (and lighter) and the reinforced bridge plate is going to be pretty stiff.

So if you use this you will need to consider how it fits into your overall bracing system.

Cheers Dave.

Sounds like a solution looking for a problem to me.

Agree.

Peter what's wrong with a traditional maple bridge plate? Use unslotted pins and I can make the same case that servicing of the bridge plate may never be necessary. We have restored a number of 1870's Martins that the unslotted pins generated virtually no wear on the bridge plate in over 100 years and nearly 150 years.

I'm a skeptic on the use of epoxy for anything that is important in the generation and/or transmission of tone. For a while I used quality epoxy for my fret boards but my friend Link Van Cleave talked me out of that making the case that epoxy is dampening in nature and very unlike the crystalline hard drying properties of HHG with these properties being the hallmark, besides ease of use once cooking of HHG use.

Wanted to add this: First off I am not trying to discourage innovation please know this.

What I am trying to do is give you a unique view into my world, the world of professional, working in the trade Lutherie. Every couple of days it seems that someone brings us a guitar from a maker who had a better idea. The better idea part is rarely the case and what does result most of the time is something that is either unserviceable, built to use and pitch when done...., or engineered by people who never learned how a conventional guitar actually functions and as such were destined to make some of the same mistakes that historically other guitar makers have made in the past.

What is always the case is that the nut, saddle, fret work, the human interface aspects of a guitar chassis.... are not ready for prime time.

With all of this said I strongly encourage people to be well schooled on conventional acoustic guitar construction such as Martin, Collings, g*bson and others before attempting to go down this route. Some of the great names in our Lutherie world have gone the innovation route and did not endure. There are lots of examples of this from the Kasha/Schneider/g*bson collaboration to others that I don't want to name publicly because they are still alive.

There is no need to mess with a conventional bridge plate design from a single, properly cut/seasoned/prepared/glued piece of wood. It's serviceable a number of ways and minimalistic as well which is always good it seems in an instrument that it's mission in life is to preserve and amplify limited vibrations to the fullest extent possible.

Thanks and again this is intended to be helpful. Much of the stuff that we see from small builders is pretty bad (no offense intended) and we usually turn it away and will not even work on it because they don't get the basics down before getting innovative and then selling the things. We have to be the ones to tell the person who spent $4K on an unserviceable instrument that we are declining because so very much of it needs to be redone that it would cost more than they paid for the instrument and we don't have the time.

We have to do this with a client at least weekly and I think a bit more often. It's very sad for all concerned.

Mr. Stock used a traditional rift-sawn (most split-resistant) plate on his guitars, and Mr. Morelli used a CF/maple laminate with the CF on the free surface. Other than a bit more work to slot the Morelli Guitar construction, I'm not certain I saw a difference, or would anticipate much in the way of difference in longevity or servicability. Unlike a laminate tail block, I never saw the need to warm the plate at glue-up, although a heat lamp would not be unwelcome for winter AM glue-ups

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A constellation only takes shape when one maps the whole.
- Beth Brower

This is a very good point. I would also add that having the bridge be rift (non vertical grain) is also wise, for the same reason. I imagine your shop sees its fair share of cracked bridges - Martins can be notorious for splitting from the saddle for instance. Poorly fit saddles (leaning) and poorly fit bridge pins can contribute to these issues. Ebony grain direction can be tricky to ascertain. But rift is definitely a good point!