Acoustic Guitar Construction

Fret Tang Fixture 08/28/18

I'm trying a zero fret on my current build; haven't done that before. I use .039” high fret wire, so Kjell gave me 2” of some with a higher .048” crown to try for the zero fret.

My osage orange fretboard is radiused to 16”, and I had used Kjell's radiusing fixture to pre-bend the .039” high fret wire two years ago, had that on-hand all bent.

The new zero-fret piece was still straight. I made a 2-part maple radiused fixture with a .032” kerf in the lower part to accommodate the tang, put the fret wire in between the parts and shut it in my vise. This required a smaller radius than 16” because of the spring back of the wire.

Stew Mac fret wire is said to have barbs on the tangs suitable for pressing or hammering into a .023” kerf, but the newly bent piece was stuck in my .032” kerf for the tang. Dug it out and put my caliper on it to find that the barbs were actually .037” wide.

My idea of a suitable fit for a .023” kerf would be an interference of maybe .005” - .007”. I figured the barbs ought to be no wider than .030” and they were .037”. Couldn't see how I could hammer it in a quarter-inch from the end of the fretboard without splitting the osage orange.

Got out a small grinding wheel for my Chinese Dremel substitute. Difficult to grind the barbs off without touching the bottom edges of the crown that mate with the fretboard, but I managed to do it. But then, I made one more pass and it got hot and discolored the wire at one end.

Bought a new 2 ft piece of the .048” high crown wire, sketched a fixture to let me thin the barbs off the tang (photo). Did the usual carpenter's one-time construction:

Routed a 3/32" dado .048" deep across the width of a scrap piece of 3/4" plywood. Notched a scrap of 1/4" x 1/4" x 6" pine crosswise with a .020" kerf using my little Japanese pull saw to engage the tang sticking up while the crown is down in the dado, to act as anti-rotation device.

Clamped pieces of aluminum roof flashing scrap down on the bottom surface of the crown (now up) to prevent damage to crown's bedding surface.

Chucked up a grinding wheel in my Chinese dremel, but never turned it on. Got a 10" mill smooth file and a little 3-cornered file that I had ground one edge safe on. Filed both sides of tang.

Sawed off a 2” piece of the thinned tang fretwire, bent it in my fixture, wiped a little Titebond along the bottom of the tang and tapped it in.

Nice work, Will. I like the zero-fret approach.
Did you find that the dust from the Osage was a problem for you?

Dave,

I'm unaware of any issues with osage orange dust.

The guy who owns the quarter section a mile north of me has a long-established north fencerow of osage orange, let me cut some from down trees. I gave some to my friend, Kjell, here (I think it's "croceguitars.com") and he used some for bridge, fretboard and headstock veneer on a uke that may still be on his site, leaving the osage the yellow it displays before exposure to light eventually gives it a nice mellow brown. He was also experimenting to try to dye it black for fingerboards as it's hard and he likes it.

Another guy who built two ukuleles for his grandkids under my tutelage last year when I built two for my granddaughters retired from owning a tree service company. He has his own sawmill and a big stash, built 6 more soprano ukes this year for more relatives, entire bodies of osage orange. He's got no complaints.

If there's a health hazard or other problem, please post it, i'm in blissful ignorance.

Nope, just askin', Will.
I had my first reaction to wood dust a few months back - Bubinga - but it was a slight reaction that caught me by surprise, as I'd used the wood previously with no ill-effects.
I happen to have a piece of the Osage in the shop but haven't begun to torture it yet.

I've been turning duck calls with osage orange, Hedge. It is great wood turning, no issue with the dust for me. Still have a guitar set waiting to be made into something to play with too.

Hedge?