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are there any 'rules' to follow when designing a cutaway?
Any help greatly appreciated.
These are pictures of the cutaway bending form for the OLF OM.



Thanks,

Frank

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Frank

Frank,
There are no rules as far as know, as can be seen by the wide variety of cut-a-ways out there.
The best advice I can give you is to draw up a few on a full size body drawing (the whole thing not just half) with at least part of the neck showing and stare at them over the course of a week or two. You'll gravitate to the stronger design over time (to your taste anyway). Also, make sure you feel comfortable fabricating what draw.
Good luck,

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Jim Watts
http://jameswattsguitars.com

A few things watch for and design for

1. Do you want the return curve to intersect flush with the fretboard and if so at what fret?

If you do then you must either account for this by having a neck block that allows for this. Many just narrow the neck block on the cutaway side, others design their neck blocks to account for this. I now have designed a neck block that will allow for right hand or left hand or both cutaways that will flush out to a 14 fret 25.4 fretboard at the 17th fret without any alteration. I am also converting for a stiletto heel to a Jazz heel



2. When at all possible plan the location of the entry curve to not affect the the Xbrace rim intersection.

3. Take into consideration the size (radius) of the press caul being use to bend the cutaway if using a fox style bender.

Too tight of a radius in the rim in relationship to the radius of the press caul radius is a hard thing to find out after you start the bend. Also to loose of a return radius in relationship to the press caul radius can lead to a bit loose though workable
bend.

4. Take a good look at how the cutaway will affect the UTB and if use UTG.

just a personal note:

I find that a 1-1/4" entry radius and a 2-1/4 return radius connected with a short tangent line works well on most size bodies and looks organic not sterile geometrical

I don't think I can add anything to what they all just said above. Stare at your drawings for a few days and the one with the fairest curve will become apparent to you.

Are you making a left-handed guitar? I normally draw my template ideas as if I'm looking at the top of the guitar. In your drawings, either you have drawn the curve as you see it looking up from the bottom of the guitar, or it's for a lefty. Which?

Edit: ....or, for a side/binding bending template, of course, it doesn't which way around you draw it.

Cheers,
Dave F.

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Cambrian Guitars

"There goes Mister Tic-Tac out the back with some bric-brac from the knick-knack rack"

Thanks for all your inputs ..

Dave:
No, not a lefty just the way i happened to lay down the template for tracing.


can't seem to get overly excited about any lines i've currently drawn.
On the 'upside' it will probably be at least a couple of weeks before any of the wood i ordered shows up.
should give me enough time to decide for a shape and make myself a bender.

this guitar will be lutz over maple with a maple(3piece)neck, ebony fretboard and bridge, all coming from shane@high mountain.
Any ideas for a binding scheme for this? thought about matching the binding with the center piece of the neck(for the 3 piece configuration)

http://www.mguitar.com/guitars/choosing ... uber_f.jpg

this is close to what i'm looking for in a nice cutaway.
snidermike had a thread here a little while ago about his latest acoustic, Beautiful guitar.


Thanks,

Frank

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Frank

I only have a couple pictures posted in my photobucket album, but this is a cut I use (maybe it would offer food for thought).
front

back


Sorry no pic with the neck attached, but I am not finished with the neck yet.

Rich

If it LOOKS right, it probably IS right......

and if you don't like it, do it different next time!!

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My soundclick xx luthier blog xx luthier soundclick

I just got the first shipment of luthier stuff yesterday that included a heat blanket& psa paper for radius bowls from john hall, and my Olf OM plans.
i marked the braces onto my template and laid it over my cutaway drawing(see pics). I'm starting to get pleased with the way i have my cutaway drawn here, is there anything that needs to be done with the bracing to keep my cutaway like this?



Thanks

Frank

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Frank

To my eye, most cutaways look a little long in the horn section. When designing my first, I spent a lot of time making it look "right" to me.
What I eventually ended up doing was reducing the size of the upper bout on the cutaway side slightly, re-shaping the curve from an inch or so from the waist. The changes are subtle, but IMHO, improved the overall appearance of the cutaway.
Some folks actually change the position of the waist on the cutaway side, moving it closer to the butt.
I also found that, what looks great in two dimensions doesn't always work in three. A cardboard mock-up of the top & sides can tell you a lot about how the finished product will look.

Frank, I just finished my first two compound cutaways (side note, I need to jig up now) on two Tenor `Ukulele. The pattern is similar to yours with the cutaway being somewhat "flat". If you take a look at the pics that others have posted, the cutaway goes up (is that the horn?) and comes back in, then curves towards the fretboard.

Because of the size, the horn and the return have similar radius'. I would follow MichaelP and do different size radius'.

Aesthetically, I would focus on the line that comes from your waist as the cutaway begins, it seems a little sharp, round it a bit, and come back in deeper. If you want to keep it "flat", I would start the cutaway a little closer to the waist.

One thing that helped me is drawing a perpendicular line from the point on the side that I want the cutaway to start. Then I used a compass and started a circle from there. I did the same thing for the "end" point at the fretboard, then joined the two lines. This took the longest, with different starting points, radius', et al. But, well worth the time spent.

Just my $.02.

Thanks for all your replies.

I like the look of a fairly 'flat' cutaway. going any closer to the waist would mean cutting the xbrace, don't know if such a thing should be compensated for.

guess i've got some more drawing to do on this...

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Frank

Dan, i took your advise and mocked up the body of template paper.
i think i've got a winner, the radiuses are different but not by much.





i'd like to go even flatter than this, but i guess i would have to modify more of the body to get a good result. and i wanted to keep things fairly simple and follow the original outline where the cutaway connects.
But i think this looks pretty good.

Do i need to make any adjustments to the braces, or can i follow the original brace plan and just stop them where they meet the cutaway?

Thanks.

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Frank