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Just wondering what is the smallest radius that you've ever successfully used or seen used and how this affected the sound of the guitar.

Cheers,

Richard.

Richard,

I profile my top braces to a 13' radius and my back braces to a 10' radius. The shapes aren't domed but a bit more complex.

I think it gives some of the archtop guitar qualities and helps with projection and mids/trebles to give a more balanced guitar. Other elements of the design and build have to be adapted to bring in bass/balance etc.

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

I have seen some pure flat toped guitars that sounded great.

Richard,

I may have misunderstood. Do you mean braces profiled with smaller radius - equals nore doming/arching, or smaller to no doming in the tops and backs?

As Michael points out either can result in great sounding guitars.

_________________
Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

Hi Dave,

You had it right..... smaller radius.... more arch.

My miss read

On tops, personally I would not go less than a 20' radius because I would think the thin-out of the bridge at the apex would be too much. That is if you sand your bridge connecting surface to match the dome as I do to avoid added shear loading on the bridge joint. If you dont sand the bridge to match the domes shape then the smaller the radius of the dome the more you are requiring the bridge to flex around the radius and or pulling the radius out of shape, thus the greater the shear load on the bridge to top joint and the more likely it is to fail. On backs I would think there is relatively no limit outsside of the flexibility of the back. Though using multi-pieces backs many lutes and other instruments have gord shaped backs.MichaelP38989.5310300926

[QUOTE=MichaelP] My miss read

On tops, personally I would not go less than a 20' radius because I would think the thin-out of the bridge at the apex would be too much.[/QUOTE]

Not really Michael. If your bridge is say 6" wide and for sake of argument the top under the bridge is a perfect dome for the given radius, then the wing of the bridge will be 0.0134" lower than the middle for a 28' radius, and 0.0288" lower for a 13' radius. A difference of only 0.0154" (or 0.39mm). This is pretty easy to design into and sand into the bottom of the bridge to match the dome.

_________________
Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

Yep, did the math and you are right.

Hey Rich .... what radius do you think you need to do what you are after - you need to figure that out first, then see if its possible. One of the other students brought over a guitar he was working on at home, it had a 13' or so radiused back. No problems at all in construction, except at the neck block we couldnt get the binding jig to cut the ledge without modding it some more - it would ride the back about an inch from the edge, thus leaving the ledge uneven.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Hey Tony... This is for the "Tele" concept... I guess I should have been more clear. What I'm wondering is if a braced maple top at very small radius, (ie. 10 foot) has any potential structural problems. Since it's going to have a pickup, I'm not overly concerned about acoustic sound...

Cheers,

Richard

I think you can make 10 ft work out fine, take the top/back down to about 100 thou or so, it should flex fine.

_________________
Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"