Bridge plate question: radius?

What're You Doing?
Kevin Sjostrand
Posts: 3712
Joined: Sat Feb 09, 2008 8:06 pm
Location: Visalia, CA

Re: Bridge plate question: radius?

Post by Kevin Sjostrand »

Thanks John, I'm just trying to understand. It seems that the bridge being thicker, more mass would act somewhat as a brace to keep the top in the convex/dome shape, just as the braces under the top are applied with a radius to do the same from the underside.

I do get what you say, if Martin and other successful companies/builders aren't doing it, maybe it is not necessary!
tippie53
Posts: 7011
Joined: Fri Mar 03, 2006 7:09 pm
Location: Hegins, Pa
Contact:

Re: Bridge plate question: radius?

Post by tippie53 »

actually that is the problem.
The top will indeed move through differing RH changes. The radius will lock things up and this will cause stress to build . I understand that you may thing this radius will help but it will only hold that under the bridge. Once the wood starts to pull the stresses will magnify pretty fast.
The flat bridge will also build stresses but not to the amount of a downward radius.
John Hall
Blues Creek Guitars Inc
Authorized CF Martin Repair Center
president of Association of Stringed Instrument Artisans
http://www.bluescreekguitars.com
MaineGeezer
Posts: 1711
Joined: Wed Aug 13, 2014 12:14 pm

Re: Bridge plate question: radius?

Post by MaineGeezer »

Lest things get too carried away here....

I just drew a 25' radius circle in CAD and drew a 6" long bridge. To conform to the radius, the ends of the bridge drop by 0.015". There is not a whole lot of difference between straight and radiused.
Don't believe everything you know.
Anything is possible if you don't know what you are talking about.
When things are bad, try not to make them any worse, because it is quite likely they are bad enough already. - French Foreign Legion
Danl8
Posts: 733
Joined: Mon Jul 28, 2014 7:50 am
Location: Chadds Ford, PA

Re: Bridge plate question: radius?

Post by Danl8 »

MaineGeezer wrote:Lest things get too carried away here....

I just drew a 25' radius circle in CAD and drew a 6" long bridge. To conform to the radius, the ends of the bridge drop by 0.015". There is not a whole lot of difference between straight and radiused.
Exactly my point earlier -- over-engineering and very tiny moot differences.
tippie53
Posts: 7011
Joined: Fri Mar 03, 2006 7:09 pm
Location: Hegins, Pa
Contact:

Re: Bridge plate question: radius?

Post by tippie53 »

think you may be right main
it isn't much so it shows you can do it any way
John Hall
Blues Creek Guitars Inc
Authorized CF Martin Repair Center
president of Association of Stringed Instrument Artisans
http://www.bluescreekguitars.com
Post Reply