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I just got finished making a template based on Cumpianos measurements for the project in his book - but based originally based off my Morgan OM.
I managed to get all the measurements within 1/16th to a 1/32nd, but a couple places I had a hell of a time blending the curves to fit the measurements, the length is perfect as is the neck and base of the guitar, its just the depth of the waist mainly & {lower bout 1/32nd shy}.
I have to go and cut and transfer this to a piece of aluminum then its time to cut up some baltic birch!
My question is this, how complicated is it to deepen the sides somewhat if one would want to - is it a simple matter of changing measurements, and consideration of kerfing material?
I would be thankful to know,
Oh yeah finally getting on something guitar shaped is a relief, not that all the shop setup chores are done - not even close.

Charliewood
PS the right side of the pic {barely visible} is the original OM tracing that was expanded upon.charliewood38856.6935300926

Charlie

Hope I've understood the question correctly, but are you trying to make the body deeper ?

If so no problem at all just make it deeper, within reason its not a problem at all, I think Froggy Bottom Guitars make several of their models deeper than average.

Thanks RussleR
Yes thats what I was asking, I was wondering if reverse kerf linings were something I should consider, and which material if any is more suitable for a change like that, basswood or mahogany? other?
As you can see I have tried to keep the OM shape moreso that what Cumpiano's drawing suggests - even though his is also close - its more of a Gurian design unless Im wrong. I was reading threads about JumbOM models with sides as deep as 5", does that sound right?
The person writing the thread said volume wise it could come close to if not match most dreads he had encountered. Im hoping the feel is a bit stiffer than my OM so I can dig in a bit deeper, without breaking up a bit.
Also I was waiting to see if anyone would point out anything wrong with my nearly near template measurements - like an oh no, what about when you................insert potential problem here.
Hopefully it wont matter much.
Cheers
Charliewood charliewood38856.7342013889

Hi Charlie

At the end of the day the standard shapes people talk about are just what in this case martin came up with, today Martins production is I guess pretty standardised, but going back the shapes and dimension varied by more than your, My OM/OOO was based on the martin shape and dimension, but I arch the back more, and my depth measurements are thinner, in fact I do a really thin version of it, so your measurement are fine.

I think any sort of kerfing will work, but I do find reverse stiffens the rim more, personally I used to use mahogany linings a lot, I don't so much these days I like Spruce and Cedar Linings, Spruce is great if you want a light look, it light strong and stiff once in place, Cedar I like for its smell.

5" is pretty deep but not ridiculous.

Personally I think if you get the bracing and wood selection right you can achieve your objective for this guitar without having to go deeper in the body.

I would say with all of these things don't be afraid to experiment, you put in your reaserch work out what you think will work, then sometimes you just have to give it a try   

Russ

Charlie

Just another thought and you may have already considered this.

You might want to consider for the future, is to make your outline templates from clear acrylic, it works easier than aluminium and another big advantage is when you are trying to decide how to place the outline on the top and back, you can see through it to see the grain etc.

Charlie, what the others said,

About the Kerfling, I have used Reversed and did not like them very well, not that it does not do a wonderful job in stiffening the rim, but I think Lance answered this question on an earlier thread, "soak them in warm or hot water before glueing" I believe was his approach, he can chime in. The other option some of the guys have shared is heating and bending on their bender or pipe. All this I found well and good, just added more steps. I like the old traditional style myself becuase I don't have to do any of these things and it never breaks. Maybe I am the lazy sort, but when they break it is really hard to fix back up. I like the cypress wood type the best.

My 2 cents

Mike
White Oak, Texas

[QUOTE=charliewood] ... I have to go and cut and transfer this to a piece of aluminum...[/QUOTE]
Hey Charliewood,

You might want to consider using 1/4" thick clear Lexan (there are other trade names - it's polycarbonate) for a template. Then, you will be able to place it on wood and pick out the very best grain pattern, and it will also be the template for your male and/or female bending/building forms. Lexan cuts a little bit better than Plexiglass - not as prone to chipping. And, easier to cut and sand than aluminum.

I also drilled little 1/16" holes at each end of where the braces would be placed, and was then able to insert a mechanical pencil with the lead extended, to mark directly on the underside of the top.

If you're planning to use a ball bearing bit, you can work from the Lexan as easily as from aluminum.

Dennis

_________________
Dennis Leahy
Duluth, MN, USA
7th Sense Multimedia

[QUOTE=charliewood] Also I was waiting to see if anyone would point out anything wrong with my nearly near template measurements [/QUOTE]
Charlie,

Your drawing looks good--well thought-out. Since the top is clipped in your posted photo though, I just wanted to make sure that you've left a flat spot (90 deg. to the center line) at least as wide as your fingerboard at the body join. Makes fitting the heel so much easier!

Flat schmat. Curve it up!

(OK, so I'm a glutton for punshiment and really don't like the look of any flat surfaces anywhere on a guitar, except maybe the headstock face and back. But for an OM, yeah, flat.)

Well yes I have left 1 1/2" at 90deg on each side of the center of the top and bottom of the guitar - I would so very much like to use clear acrylic/plexi/lexan and will be purchasing some, alas aluminum is all I have onhand right now. I will have to reconsider depth, as the slightly larger body wioll achieve the stiffer playability that Im seeking somewhat on its own, of course I cant find the thread on mimf again!
Thanks for all the tips.
Cheers
charliewoodcharliewood38857.4996180556

[QUOTE=Mattia Valente] I'm a glutton for punshiment and really don't like the look of any flat surfaces anywhere on a guitar[/QUOTE]
I agree with you, for the most part (I kinda like Gibson's LG series body); but, for a beginner (such as myself), having a flat spot against which to register your heel is pretty much manditory, if you want a tight fit. If you plan ahead, though, you can start your upper bout curve right at the edges of the fingerboard and the flat area all but disappears.

Flatspots hmmm, Next time Ill make a Weissenborn, no flat spots where the neck meets the body there,
Thanks everyone.
Cheers
Charliewood