Bridge plate thickness

[rienk]

Sorry, probably I missed something, but why hate EIR for this purpose?
I guess I have to admit I cannot tell what bridgeplate a guitar has by playing or listening.
Is it the amateur in me?
Herman

I am curious about this as well.
I know that people can tell the difference between soundboards and tonewood, but I have yet to have an expert say they can measure - let alone hear - any difference between different woods for bridge plates, kerfing - even bracing.
Our local guitar shop owner (probably 500 guitars - and his private collection is probably worth $1M) is adamant that such perceptions are anecdotal, and perpetuated by myth... the main bridge plate issue starting when Martin changed a few decades ago (I forget the years).

As a newbie, I don't know who to listen to about such things. So obviously, true measurable (and verifiable) data is the only thing that makes sense.

Where can that be found?
I assume several on this forum might have access to that?

[tippie53]

I agree kerfing is not going to change tone but braces and bridge plates ( more by size ) than species will. It comes down to weight / strength ratio. The physics of the bracing material will indeed influence the tone.
One reason that I don't care much for East Indian is that it wears faster. I have taken a number of Rosewood plates out and replaced with Maple which resulted in a change in the tone of the instrument. You want a material that can take the wear better than others. That doesn't mean all Rosewood is bad, but as a whole, there are better materials for bridge plates.
When you look at braces, it is the weight and mass that you want to take advantage of. The lighter you can make a guitar, is often better than a heavier one. There are so many variables in building a guitar it is difficult to say what single process is more important than another. I would say that anything that effects the mass of a major part in the bracing will effect the tone.

NOTE:
If I can make a brace out of a lighter stronger wood, I can make the brace lighter and as strong. This will lower mass and change the physics. It is all about mass and physics.

[rienk]

If I can make a brace out of a lighter stronger wood, I can make the brace lighter and as strong. This will lower mass and change the physics. It is all about mass and physics.

Which is why I am interested in Truss type bracing - it is the strongest and lightest system available for any given wood. And in theory, a laminate is the best for that -which is why I am intrigued with using Baltic birch plywood. Should be an interesting experiment!

[tippie53]

Most of the builders that laminate still use the main wood as spruce as it is still the lightest and use anything from carbon fiber to ebony.
You are correct that you want light and stiff but you also need to be able to control the stiffness . Martin even use aluminum for a top on a series of guitars. It was very forward thinking for them. They actually did sound ok. The back and sides were HPL .
I started building before the were many sites on the net but it is difficult to find accurate information . We are here to help so please don't get too frustrated , you may be asking questions for which we may not have an answer. Also you didn't even start discussing glues yet,

[rienk]

Most of the builders that laminate still use the main wood as spruce as it is still the lightest and use anything from carbon fiber to ebony.
You are correct that you want light and stiff but you also need to be able to control the stiffness . Martin even use aluminum for a top on a series of guitars. It was very forward thinking for them. They actually did sound ok. The back and sides were HPL .
I started building before the were many sites on the net but it is difficult to find accurate information . We are here to help so please don't get too frustrated , you may be asking questions for which we may not have an answer. Also you didn't even start discussing glues yet,

To me, the experimentation is part of the allure of guitar building!
I love thinking outside of the box - though right now I'm focusing on the inside (engineer's attempt at a pun).

Yeah, don't get me started on glues... yellow, white, hide, fish - I actually bought all of them.
I happen to love epoxies and resins (I literally buy the stuff in drums) but you might as well give up on the idea of being able to repair the guitar (is planned obsolescence okay on a $1-5k guitar? JK).

And though I like carbon fiber and work with composites every day, I am intrigued wth using traditional materials in a modern way. In fact, I'll probably make an acoustic guitar mold in some non-symetrical shape (Jaguar or such?) just to have some fun.

Like both John's imply, you have to experiment, and keep track of what each change does - what works and what doesn't. The hard part is changing several things at once, and knowing what caused what (on top of the variations that two different pieces of wood can cause, this is probably an impossible task to attribute correctly). It kind of reminds me of how the ancients discovered their medicines and remedies... at least with guitar building people aren't dying if you tried the wrong combination.

Back to bridge plates: I really like Ryan's laser cut honeycomb bridge plate - that is taking lightness to a serious level. I will probably try something like that after I get a few builds under my belt.

So, beside wood species (and glue) what other fun stuff is there to experiment with regarding bridge plates?

[tippie53]

As far plates I think the size has more effect on sound . Thickness and shape. I know of some builders that lay brass and aluminum plates under the bridge for the ball ends. There are many things and it is like a puzzle. The one thing I can't stress enough is that aside from the obvious that the box had to withstand the stresses , it is the braces top and all that , that plays with the physics , so in the end the result will give a subjective response and it will rely on the listener or player for the tone and voice.
Once the subjective input is used, it is like asking what is your favorite color or flavor of ice cream. Once you understand the way the top is influenced for bass and trebles, you can make the flavor how you want it. Often the bass response is magnified at the cost of treble . I shoot for a balance across the spectrum .
Hope this gives you something to think about.

[Coach]

How about purple heart as a bridge plate? What charasteristics, Anyone use it, recommand it?

[Tom West]

John Hall has given some real solid points on plates. In my mind the area of the top where the plate is located is the area most sensitive to changes of weight and stiffness. I look for hardness with light weight and a bright ring when dropped on the bench. Also beware of woods that may tend to split or crack. Hard to get a perfect wood but some are better than others. As far as EIR goes most peices lose out to other rosewoods on the drop test.
Tom

[ruby@magpage.com]

Ash has the highest strength/weight ratio of any common wood - even better than Sitka Spruce. Frances Herreschoff built a 70 foot hollow box sailboat mast out of 3/4" ash in the 30's. Problem is that it is not available in long lengths, but then we don't need them for guitar work.

The surface of ash is hard and it is stiff - would it make a good, thin bridge plate? braces? I have been considering making an entire guitar out of it - top, back and sides, even the neck. Anybody have any experience with it?

Ed Minch

[tippie53]

Can you do a topic discussion of that Rick? I am sure we would like to hear that.
When I do a top . I am a fan of the thickness of the top and weight prior to the bracing. Also do deflection of the top pre and post bracing so the top is stiff where I like it.
It may be we do the same end result a different way.