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Does Martin guitar use a radius dish or something to that effect?
I noticed that a radius dish makes a guitar somewhat parabolic throughout it's length yet on my Martin D35
only the back of the bridge is raised about 5/32 in the middle.
I layed a straightedge along the edge lengthwise and in front of the rosette it actually dips about 1/8.
Is it a different construction method?
Ronald

yes Martin uses them, one for the top and one for the back.

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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

Kenneth from KMG has an article about how Martin sands a 1.5 degree slope from the waist to the neck block to facilitate the neck angle... Is there any truth to that?

http://www.kennethmichaelguitars.com/neckangle.html

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Don't confront me with my failures--I have not forgotten them.

I am an Authorized CF Martin Repair Center . Martin uses 2 different back radii. One for the Dred and 000 and smaller . The top is set up with the neck angle in mind. You can actually see the back curvature. the top is set up with a higher radius and the radius is set so there is a 1 1/2 degrees neck angle. I have studied the radius machines at the plant on many tours , as last count over 54 , plus I get to visit the repair department any time I need to. I am going out there again next week and will take some pictures of them machine.
When you take the tour you can see the rims in the molds, before and after the radius process, and you can clearly see the the whole rim is sanded on sides and on careful study you can see that the lines are not dead flat.

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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 know you know what you are talking about, John. So in short... is there any truth to what Kenneth was talking about in his article? Because it makes sense to me that the top of the rim is sanded to make sure there is a 1.5 degree slope at the neck block. But he goes further to indicate that they may actually create a flat slope from the waist to the neck block.

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Don't confront me with my failures--I have not forgotten them.

That rings a bell, Matthew. I can't remember where (which means it may well have originated in my own tweaky brain), but I thought I read that this was done under the direction of Michael Dresdner, who invented the A-frame bracing for Martin, as on their 16 series guitars. If memory serves, this is also how Cumpiano sets out producing the neck angle in his book, using a big flat sanding board to make the slope from waist to neck block.

Peace,
Sanaka

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...imagine there were no hypothetical situations...

Yep... Forgot about Cumpiano's method but you are right.

_________________
Don't confront me with my failures--I have not forgotten them.

Martin did not invent A frame bracing.

Perhaps "invented" is too strong a word: in the sense that most methods and structural arrangements in instrument construction are derivative or evolved from earlier ones, I'm sure you're right. In any case Martin doesn't defer to anyone else on the idea, and the A-frame members are central to the Dresdner/Martin patent for this bracing pattern.

Peace,
Sanaka

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...imagine there were no hypothetical situations...

No it isn't flat , this is done on a machine the spins a disk. In all fairness to ken it may be how they did if long ago but it isn't they way they do it now. The disk has a slight radius and the mold is jigged to assure the proper angle within that 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

Martin most certainly did not invent A bracing! Both Roger Bucknall at Fylde Guitars and George Lowden were using them back in the 1970s, well before Martin decided to 'Invent' them, and, I doubt if Roger or George were the first. Just because someone decides to patent an old idea, doesn't mean they were the first to think of it. Look at the Novax fan fret, a system used on Orpharions for centuries. And don't get me started on the X brace.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

What radius does Martin use on the Dred, top & back ??

Gregg

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Gregg

George Lowden was doing that A-Frame bracing on his guitars long before Martin patented it. They may have gotten a patent, but it would be easily challenged.

When I ask at Martin get a number of different replies , but from what I can gauge off actually bodies I see 15 on the backs of the 000 and smaller , 20 on the dred and the top has a 40+ foot or there about but the top is also angled . Most of use us the 28 disk as that will equate to the 1 1/2 degree angle . Then when you look at the Martin bracing not all of the top braces are radiused. That will help to flatten the Fretboard area.
I hope to speak with someone in the know this week at Martin and see if I can get a good answer from them , But lets be honest , they are a very open company but they have the right to withhold some information to protect themselves.

_________________
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 Colin and David,

I didn't mean to really defend Martin, even though I had over the years formed the idea that Mike Dresdner made up the A-frame for them. I'm not as steeped in the lore as I would like, and am happy to be set straight!



Could you be enticed to, in fact, get started on it? Was the X indeed not a gift from God to CF Martin I?
(This is kinda OT for this thread however...)

Peace,
Sanaka

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...imagine there were no hypothetical situations...