Flatsawn osage orange
 

Good morning all,

A friend of mine gave me a nice piece of osage orange that is about 4 ft long, 8 1/4 in wide and a little over an inch thick. However, it it flatsawn. I was curious if anyone has had success using flatsawn osage orange for guitar back/sides?

Thanks,

Danny

A quick look at the Wood Database shows this info for Osage Orange:

Shrinkage: Radial: 3.8%, Tangential: 5.6%, Volumetric: 9.2%, T/R Ratio: 1.5

Honduran mahogany is a good stable wood to compare it too and that is:

Shrinkage: Radial: 2.9%, Tangential: 4.3%, Volumetric: 7.5%, T/R Ratio: 1.5

So you are pretty close to the gold standard of stable wood. Ideally it's always better to have vertical grain wood for stability but my guess is that if you built with it under controlled environment it will be okay.

If you control the humidity you can get away with a lot of the flat sawn material some people are using.

Of course you have to control the humidity forever, and if the material is of questionable stability, it just takes one slip-up and. . . . Ruh roh.

The comparison with H Mah. a couple of posts back does not make them look similar to me, it actually shows a 30% difference, which is a lot.

Thanks for the input everyone. He had this wood for a long time, I actually thought it was a piece of cherry when I brought it home, then ran it though the planer and saw the color of the wood. There is no warping or cupping, but it will be a while before I try to make a guitar with it. I may wait until I can find some quartersawn.

Danny

Osage and black locust are relatively stable woods, particularly when you consider the density. I tend to evaluate each piece of wood individually, considering its age and amount of warping. One way to help insure against cracking is to make sure the back is very dry when the braces are glued on. So far, that philosophy has worked well for me. One of my first guitars has a flat sawn black locust back, and it is 41 years old with no issues.

I believe Tim McKnight hs experience with Osage orange. Perhaps if you reached out to him you would get a good answer.

Dry Osage Orange is pretty stable. I used some flatsawn Osage for some thin-wall shaker-style boxes (the round ones that require side bending) and they’ve held up for twenty years, used daily (they’re kitchen storage). It’s got some stains but no cracks....

i use osage for duck calls (best domestic wood available for sound and durability). Once its dry, it seems to be very stable. If not dry, it moves enough for a 5/8 tenon to swell overnight and lock a call together permanently.

I think I would go ahead and cut it into 1/8" slices, then let it season/stabilize again for a good while. Then you can judge how stable it seems to be...

This is what I am planning to do, so far there is no indication of any splitting/movement. The bigger challenge is having the patience for my 14 inch JET to cut through it. I'll use the table saw to begin the slices then the bandsaw to reduce the stress on it. I think I will have about 3/16 in for each slice after sanding.

Danny

Was the osage kiln dried or air dried?. If air dried, for how long and in what conditions?. This info will go a long ways toward knowing how it will hold up in a finished guitar.

I believe it was kiln dried, he had it in his garage for several years.

However the wood was dried, the stresses need to be relieved. During air drying, that occurs over time, particularly if the wood is exposed to cycles of varying temperature and humidity. That is the definition of 'seasoning'. Proper kiln drying of dense hardwoods should include an additional step called normalizing, which will relieve internal stress. When resawing, you will know instantly if the wood has stresses, because the outer layers will tend to cup.

I have normalized metals in ovens. Wonder if you could do the same for a piece of wood? Would have to sit in a jig until it absorbs enough humidity though.