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#4 is an EIR/ADI my first OM . I am on long service leave for a couple of weeks at present and have been able to spend some quality time in the shop. I've been amazed by how much quicker this one is coming together.
I have decided to go with a pretty much standard Martin brace pattern for this one. The Adi top is .110 . The braces are 1/4 sitka. 1/2 inch at the X crossing then tapered down.
X is forward shifted. 9 inches from neck/body join. Bridgeplate is maple at .105 .What do people think? I didn't want to over build but am concerned I might have gone too far the other way this time.

Regards

Craig.

Craig: If that top is a bit on the stiff side,I think that guitar will be a killer. The .5 is a bit under what I would use but then I'm a bit of a chicken....!!
Tom

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

No way is that top 'under' built Craig, I will not say more as I do not have the builds under my belt to qualify and I do not know what you are after in a guitar. I will say that if you ever want to put an endpin jack through that tail block to service any kind of pickup I reckon your going to have a hard time finding one long enough..

Cheers

Kim

Tom as this is only #4 I still havn't handled enough tops to know for sure but I would guess average stiffness.
Kim I know why you have the eye as your avatar now. Well spotted . Thanks. I might have to countersink that a tad before I glue on the back on.
I wanted a guitar that will handle med strumming but shine with fingerstyle.

Thanks again for your replies

regards

Craig

Awesome.Are you using plans for this OM build Craig? Looks so much like my OM build! Can't wait to hear how the results are with your bracing! I hope it's everything you're looking for. What do you predict is the advantage of one long taper instead of multiple scallops?

Alexander I found some plans on the internet drawn by C Grellier. I have followed his layout reasonably closley however instead of using 5/16 main X braces at .625 I dropped down to 1/4 at .5 . In order to keep some stiffness around the bridge area I decided against scalloping instead going with a taper from the first fingerbrace. I'm fairly confident it will hold up againt string tension just not sure soundwise how it will be . I can't wait to find out though.

Regards

Craig.

Keep in mind the old cube rule: for braces of the same width, a 10% decrease in height equals a 30% decrease in strength.

The drop from .625" to .500" is 20%.

Probably good to stay away from medium strings.

Looks very similar to my first OM which turned out sounding very good. With mediums. Of course there's no telling how the two might compare in stiffness. Mine's only 1 1/2 yrs old so it might implode eventually.

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Steve Smith
"Music is what feelings sound like"

Steve that is encouraging to hear although I think I will probably stay with lights on this one. Have you noticed any deforming of the top around the bridge area?


Regards

Craig.

No deforming at all.

_________________
Steve Smith
"Music is what feelings sound like"

Steve do you recall what your bracing dimensions were, height at X crossing ? Was the bracing forward shifted?(distance from neck/body join to front of X). Thanks.

Craig.

Craig, I didn't keep good records but the X was about 1/2" (it started higher but I cut it down). Front of the X is about 8 3/4 or 9" from the top of the body. Scale is 24.9 and its a 14-fret neck. The cross braces were 5/16 wide and the others were 1/4". I started out with a scalloped pattern but the top sounded dead. It was just way too stiff so after watching John Mayes voicing video again, I tapered everything till it sounded good. I was nervous when I first put strings on it (lights) but everything stayed in place. After about a month it was pretty obvious that the guitar needed mediums to really drive the top so I may not have built it as lightly as I thought.

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Steve Smith
"Music is what feelings sound like"

Thanks Steve that gives me some confidence to go with what I have. The only main difference with mine is that it will be a longer scale length so more tension at concert pitch. I'm not sure but this could be equivalent to the difference between light and med strings . What is the height from the top to the bottom of the low e string on yours? The difference between .5 and .4 inches is quite significant in how the top is driven.

Regards
Craig.

From the top to the low E is 0.44" at the bridge. I went back and looked at what I wrote when you mentioned your scale would be longer and I put down the wrong scale. This one has a scale of 25.4". I've got 24.9 on the brain because I'm building two right now with that scale length; a 13-fret 000 and a 12-fret size 0.

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Steve Smith
"Music is what feelings sound like"

Same as mine Steve 25.4. My bracing at 1/4 inch works out to be 20% less stiff. As you said before there is no telling how our tops and bracing stifness compare but assuming average for both I think it will be close to the mark. I will aim for a string height of .45 inches and work it from there. Thanks for your willingness to answer my many questions.
I will post more once she is together. Can't wait.

Regards

Craig.

Good luck with it Craig, I'll look forward to seeing the result.

_________________
Steve Smith
"Music is what feelings sound like"