MIMF

I am new to guitar building and have a question about backs and side wood. I came into possession of a black walnut tree a number of years ago, very beautifully colored, tight grained wood. I am not able to quarter saw wide enough pieces to make a dreadnought size guitar back. What are the drawbacks of edge gluing 3 or four narrower pieces and re-sawing them to make book matching pieces for the back of a guitar?

Thanks for your help?

do it!

The only drawback is the extra glue joints you have to make. If it's a choice between doing that and tossing out some perfectly nice wood with an interesting provenance, I'd do some joining.

I have had really good results with slab sawn walnut in archtop guitars. The boards were just a little too narrow, so I used the off cuts from the waist area to make up the needed width at the lower bout. With a little finesse these extensions will blend perfectly with the rest of the plate.

I think slab sawn walnut looks way more interesting than quarter sawn. Opportunity to celebrate "cathedral" or other grain figures, or even lighter colored areas that were closer to sap wood.

The guitars have a nice woody tone. Go for it!
//mike

Slab sawn wood is less stable than quartered. You can get away with it more easily on an arched plate, since it's not as constrained by bracing and can 'breath' a bit to reduce stress. Although walnut is more stable than most woods, I'd still try to stick with quarter cut, even if it means making more glue joints.

Thanks for the input. I think I have enough pieces of 1/4 sawn walnut that will have good grain and color match along with some interesting effect. I am not worried about strength since well made joints using modern glues are generally stronger than the wood itself and have an amazing longevity. My main concern is the effect to the tone of the instrument. The input you all have given convinces me that I worry for no good reason. Thanks I'm give it a shot. Any other advise will be appreciated.

Walnut is widely available in sizes sufficient for two piece back and sides, so I think gluing up small stock is sort of a false economy. But you can certainly do this if you want, and there should be no down side other than the extra work.

yah there is a lot of walnut available, but not from a tree I harvested, hauled, sawed and dried, that has great color, close straight grain grown in Montana.

I've seen several guitars with 3 piece backs in which the joints were accentuated by strips of inlay. The centre pieces were often wedge shaped. Looks great!

A well made three piece back should have no effect on tone one way or the other.

I like the idea of a different wood for contrast in the back. I may settle for a maple or ebony center strip. Might need to be larger than I'd like.

Thanks for the ideas !!!

I would have absolutely no problem with a 3 or 4 or even more piece back. I have not done it with walnut but yes with mahogany. I make mainly classicals so the waist is quite a bit deeper that a dreadnought. What I have done on classicals is used the waist cutout as "wing" on the lower bout to make up the extra width. I doubt is anyone who was not told would find the joins with a lens of some kind.

I have some (bought) UK walnut with has some side pieces so wide that I am am thinking of trying to convert my 4 sets in to 5 sets by glueing on bits in places … not a project for today or tomorrow but it might happen.

You can saw a board into 3 slices and get consecutive faces for a nice effect. I have made it but not used it. May some day.

Flat sawn is used a lot, from the post I read here and elsewhere. Looks seem to rule the day

Thanks for all the input. Bob, I do a lot of woodworking, (heirloom furniture) and wood movement is a big consideration when you want your build to last a long time. For that reason I want to steer away from flat sawn. Good luck with you piece.

Movement is accommodated with bowed back and bindings at joint; it seems to have worked over time. The test of time seems to be it. Best practices.
Think about all the flat sawn maple in musical instruments.

I get that movement in a flat sawn back can be accommodated by bindings and bow. What about bending sides? Won't run out cause problems both in the bend itself as well as the final appearance?

Flat cut sides can cup badly, particularly the 'flat' spot below the waist, and I tend to avoid them even more than flat cut in the back. Sometimes you can't avoid it, of course, as with birdseye maple, but I try to avoid it when possible.

I have read many post about reluctance to cut up a beautiful figured flat sawn board of say sapele or maple because of problems. Then a few months pass and then they go for it. Others then chime in that they did the same and got away with it.

I too have many beautiful boards but flay sawn. But I am sticking to quarter sawn for my first few. But in a few years...

On #2 now.

Have you heard anything about bending problems with flat sawn? I would think grain run out would be very problematic. I can use 1/4 sawn for a number of guitars, but wonder about using flat sawn for sides. Would give some spectacular grain to go with the back.

In my limited experience flatsawn bends quite easily and quartersawn is harder to bend. I think of it as a couple of sheets of paper bent longwise compared to a stack of tiny I-beams. A lot of the impressive grain in maple is down to the flatsawn aspect, and when I used it last I got cupping. It bent perfectly flat and true, and was cupped by the time I got around to gluing up the box. Around 1/32 across 2 5/8", or even a bit more, and I didn't manage to take it out by sanding, I left some of it in as I was afraid the sides were going to get too thin.

Brian