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You do need to decide whether you want to take the bindings around the corner to bind the end of the cutaway side - like this PRS example. Best to mitre the corners if you do.

Or you can keep the front and back bindings separate, like this Goodall example.


These pictures also demonstrate the options of wide heel (PRS) or tapering heel (Goodall). Choose your own adventure.

I’m not a builder of cutaways, but I am curious about one aspect of the differences between the two options set out by Mark (well done, by the way):

It seems to me that it would be difficult to have a good looking flush joint (top option) unless you attached the neck, and then finished the whole guitar assembled. But with the bottom option, it seems like it would be easier to do what I do, which is finish the neck and body separately, then put them together.

Is that right, or not right? Again, this is a question for those who do this from someone who doesn’t.

I do cutaways like option 1. I finish the neck separate from the body. When out together they look fine. Just need a tight clean join.

It is a good question Don. I have done it like Glen says. I have to admit my join is not perfect. For what it is worth here is a youtube video from the PRS factory showing that particular model has a glued dovetail neck joint and it gets sprayed after the neck is joined. Many ways to skin a cat.
https://m.youtube.com/watch?v=2-VqUSwkyjk

I do option #1 for my cutaways and I finish the neck and body separately. That doesn't present any problem for getting a nice tight joint that looks good.

I prefer having the heel side flush with the end of the cutaway side because I don't care for the sharp corner that option #2 leaves there both aesthetically and for how that pointy tip of the corner feels against heel of the left hand. The corner I'm talking about is more obvious in the first photo below than in the second photo Mark posted above.

If the heels on my guitars had a tapered design and I wanted to do a cutaway, I would want to eliminate that corner the way it's done in the second photo below.

_________________
Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Jay that's a really neat way of tackling this issue. I imagine getting all that geometry right would be tricky...?

Dave

Jay that is a very good question. I am not sure at the moment, I need to research that.

I do like option #1 as it flows better than option #2.

I agree with Jay about the aesthetics. That corner just doesn't relate well to the tapered shape of the heel. The wide heel blends better with the cutaway - at least to my eye. This question is exactly the one being kicked around in the "compound cutaway" thread that Pat Hawley started (some good thoughts there). I think that option looks very elegant, but is a little bit more challenging in terms of shaping of the neck block and bending of the cutaway side in three dimensions rather than two.

Of course, you can do it without a heel at all!
The new Martin SC-13 E

Tacoma thunderchief

Myka guitars

I personally don't like any of those solutions but that's just me.

I recently did my first cut away as well. One thing that really helped me was a video that was over on O’Brien’s page. It’s not free, but it does explain a lot and shows you step by step how to make it happen. Just an idea


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I don't like them all either, but I just thought it might broaden the discussion..........

I was looking at Robbie’s course the other day, should be an excellent resource.

Jim D'Aquisto let the wood of the side determine the shape of the cutaway. Makes sense to me.

Patrick I wonder how your bend your sides? These tight cutaways can be quite a challenge. I am pretty hopeless on the bending iron so have a fairly elaborate bending machine which keeps tension on both sides of the wood.
I take the thickness down to 1.8 mm on the cutaway side.
There is also some careful fitting of the linings needed in the nose. I don't try for continuous but look for a good fit and hence good glue joint.

It is very useful if you can bend the bindings at the same time as the sides.

This a recently completed classical which I was pleased with the bending. Dave

Mmm hmm. Simon Fay brought this up here a few years ago. I try not to have a flush joint where the side of the heel meets the side of the cutaway at his recommendation because (1) the finish will want to round over around the edges, and (2) is also prone to chipping without a little relief worked in by rounding the edge. The side of my cutaway is about 1/32" proud of the side of the heel. This mitigates the effect by making it look intentional. Getting that geometry correct is still the most difficult step of making the cutaway rim for me.

More from that thread here: http://luthiersforum.com/forum/viewtopic.php?f=10101&t=45183

Funny enough, the guitar in that thread was the first one I built on my own that had a cutaway. I never came back to that thread to complete the story. I ended up finishing the neck and body separately. I didn't have any problem with round over of the finish and the joint came out tight and dead flush. I've done three cutaways this way and all three came out the same way. If you look closely, you can tell that the finish wasn't applied over the joint, but that's the same as the neck-to-body joint on the bass side of the heel, and on both sides of the heel on non-cutaway guitars, which we are used to seeing without finish over it (at least on steel string guitars). I really haven't found it hard to get the surfaces of the cutaway side and the neck heel to line up flush. Leave a little bit of extra wood on the treble side of the heel, attach the neck to the body, and then sand the heel flush with the end of the cutaway side.

When it came time to level sand and polish the finish, I followed Simon's tip and did all that with the neck attached so there was no rounding over. There hasn't been any chipping of the finish at the joints.

I'm wondering if applying the finish after the neck is already attached to the body wouldn't make a neck reset more complicated than it needs to be.

_________________
Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Dave to answer your question I use a fox bender to bend my sides. I need to retrofit it for the cutaway press. I did purchase O’Brien’s Venetian cutaway course and that helped me visualize the additional steps for this build.

Patrick good. Robbie has lots of sensible things to share with us.
As I think Alan said above I don't try to force the cutaway right into the mould. So long as it is roughly OK I live with it. But then I'm an amateur and don't have to produce specific models for sale.

Cheers Dave

I am considering using black walnut for this build, should I stay away from curly or highly figured or does it bend fairly easily?

Dave nice work on the classical guitar, beautiful. What species of wood is that?

It is pretty isn't it. It is Indian Rosewood bought by someone about 25 years ago which I have acquired so perhaps better quality than one can buy today.

I have used American Black Walnut on the same shape and it bent pretty well. It was pretty straight grained though.

Dave

Curly walnut, maple, and koa have been pretty easy to bend on a hot pipe with the right technique. That said, while some of the bends I've done with those woods were fairly tight, they weren't as tight as the horn bend on your cutaway plan so I don't know if that would present a particular challenge for curly wood. One thing I learned was to not spray water on the outside surface of bends, spray only on the inside surface. The tops of the curls are weak because the grain is coming up out of the wood. Getting those spots wet further weakens the wood fibers and they can separate at the tops of the curls leading to a crack. With spraying only the insides of bends, I haven't found those woods to be any more difficult to bend than other woods.

Other types of figured woods I've used have been variable. Highly figured ziricote bent nicely, but the Macassar ebony sides below would not bend flat even though the were bent in a bending machine. The sides came out ripply which made level sanding them without sanding through a big problem. The ripples corresponded to the figuring pattern. The bubinga sides below were a real bear on the hot pipe. They wanted to make facets about the size of a quarter instead of smooth bends. They took a lot of work.

_________________
Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Walnut is one of the better species for bending, so that is probably a good choice. Thin that section of the side down to about 1.8mm. I use SuperSoft2 as well. The bends that I have used SS have all gone well (except some ebony bindings, sometimes nothing can save those).

Jay really nice work and good information regarding wetting the inside of the horn bend. I plan to pick up some black walnut orphan sides to do some test bending. Worse case I make some inserts to lessen the curve in the cutaway. Mark I use Windex with success wetting sides before bending. More misting than wetting.

Here is my mock-up for the cutaway. A couple of mods to the form and cutaway press and I am happy with the results.
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