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Where can I find a good example of forward shifted bracing? Is there a scale length that complements this type of bracing more than other scale lengths? I'm using a plan that I bought from LMI drawn by Scott Antes for an OM! I found this example on the Stewmac site.
http://www.stewmac.com/tradesecrets/ts0051_xbraces.hzml

What more do you need?

I like using information from more than one source! Anyway.
Does anyone have advice on forward shifted bracing or is it as cut and dry as Stewmac makes it look?

Can't recall right now but the angle of the X brace is different than a dread and the distance from the inside of the X to the sound hole varies from 1" - 1 1/8. My 33 OM is 1 1/16.
Tim

I've only made one dread and used the forward shifted SM approach and it is just that simple. Open up the X a bit and move it North.

This guy seems to know what he's talking about.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

I studied a number of prewar 1937 martin D 28's and D 45s The bracing on them is pretty close . Wayne Henderson and I compared our information.
http://www.bluescreekguitars.com/shop/i ... cts_id=270
this is the end result. It is the pattern I use for my pre war commissions
http://theunofficialmartinguitarforum.y ... QJ2RfIl2NA

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

The Martin Bracing Library in the Technical Info of the UMGF may also be some help.
Tom

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A person who has never made a mistake has never made anything!!!

And charge an additional $300

I know that many changes were in warranty issues. In 1937 the neck block was 1 9/16 this changed by 1939 to 1 3/8 . Many tops had issues from that and the Popsicle brace was added. Also there were many process in the company that were HAND done and a certain amount of variability is often seen within the examples.
I agree with Todd the the Greven posting is his own opinion and while he has indeed worked on many guitar it is still his opinion. Many changes were small some larger. The end scallopes and taper , is one example , the enlarged bridge plate swapping maple to rosewood and back to maple side supports from cloth and to wood as just a few .
They changed to cold glue in the new factory. So there are so many tweaks , some good some not so good but I do believe more was done for cost and production than anything else. CF Martin is a production factory not a luthier shop so they look at the product in that manner.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I bet John Arnold would be willing to talk to you about it. I hear he is a great guy. Maybe shoot him an email.

Also, John Hall, the word is spelled "notch" not "knotch". Get your your web guy to fix the spelling on that Waldron template page.

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http://www.CostaGuitars.com
PMoMC

that is my spellin I are guud at it

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I have forward-X patterns for OM's and dreadnoughts (and many others).
The Stew Mac article has inaccuracies. No Martin dreadnought or 000 I have ever seen has a 100 degree X-crossing angle. 97 1/2 to 98 degrees is common on most Martins, except for the low-X braced ones, which are 94 degrees. And Stew Mac makes no mention of the fact that the tone bars are closer together on forward-X Martins.

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John

See? John Arnold was willing to talk. Nice guy.

John Arnold,
Do you think the 2 degree difference in X angle makes much of an impact on the sound/ tone/ volume?

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http://www.CostaGuitars.com
PMoMC

Probably not, but I haven't tried it. I do know where I like the braces to intersect a standard 6" long bridge, and the 98 degree angle works for that.
Another consideration is that Gibson uses a wider angle on many models, but that couples a short scale with a round-shoulder dreadnought body.

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John

Except for the AJ which is 25.5 or thereabouts. Mind you, the top on mine is .155 at the sound hole...