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Hello,

Does someone have the radius value for the TOP and BACK of the Martin 000-28 ? and for the fingerboard ?

Thanks a lot

Give John Hall at Bluescreek (sponsor) a call. He'll not only know, but if the radius was ever different by year or any other quark, he can tell you.

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Bobby Masten

I purchased my Martin kit from John to give a go at building a 000-28 and he sent me 28' and 15' radius dishes for the top and back respectively.

Marc

You also asked about fingerboard radius, John told me it was a 16.

Marc

Hello all;)

Thanks you very much for your help...

John say me that the top is flat and the top braces are 42 foot radius, the back is 15 as for the braces...

Technically the top has a 1 1/2 degree worked into it. The top of the sound hole to the neck block . The backs are 20 on the dred and 15 on the 000's on down. We use a 28 foot disk as this will equate a 1 1/2 degree angle . The actual martin top bracing is 42 foot radius.

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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

Hi !

Thanks you for your answer.

So if I have understand, I need to make 42 foot radius for top bracing, glue it and use a 28 foot radius dish to sand the kerfling ?

Can you tell me wich braces are radiused on top (only the X braces and the brace up the soundhole ?)

Thanks you again all

Don't feel bad Alexandre, I ain't tracking either.

John, you saying from the top of the sound hole to the neck block is 28' radius and from the top of the sound hole down it is a 42' radius? So, in effect, the top has two radius's on it?

Hutch

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"After forty-nine years of violin building, I have decided that the search for a varnish is similar to the fox hunt. The fun is in the hunt."
Jack Batts Maker and Repairer of Fine Violins

Chuck, not to speak for John.........but I think he is saying the top has no radius from the top of the sound hole to the neck block. And I think he is saying he uses a 28ft radius on his tops (John's personal builds) but that Martin gives their braces a 42' radius before glueing to the soundboard. At least that's how I interpreted it.

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Formerly known as Adaboy.......

From my dealings with John, what Daryl is saying is exactly the way I understand it to be.

Marc

What I am saying is that martin uses a radius of 42 foot on the top bracing. The sides have a 1 1/2 degree ground into the that relates from the upper soundhole to the neck block. There is a slight radius on a top after gluing and when the top is glued to the sides the 1 1/2 angle on the sides actually bends the top slightly to accommodate the neck angle.
You can make a jig to do this but I like the 28 foot radius on the top as I do it in the video. This creates the neck angle into the sides. I am not a fan of sanding the angle into the top as this thins the area where you need the material .
In reality there is a flat spot on the upper bout 1 1/2 degrees and a slight radius on the rest of the top. In reality one you glue up the braces , they are subject to relative humidity and the torque of the bridge .

_________________
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

Thanks you very much, It is very clear now...

What about the top braces, Martin make the 42' radius on all braces (X and horizontal) ?

Thanks.

the only braces that are radiused on a Martin are the top X
the backs may be 15 to 20 depending on what they are for

_________________
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

John - if I understand correctly, the only top braces on a Martin guitar that are radiused are the x braces; the tone bars and finger braces are not radiused. Is that correct?

that is correct.

_________________
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