Use wood filler on scratched shaft?

[Sloppy Pockets]

Professional wood workers often use an interesting technique to fill gouges and scrapes. They mix sawdust (of the same wood type) with cryo glue (super glue) and fill the area. When the patch is dry and sanded, it is totally invisible. I saw a wood carver do this once and couldn't believe the results.

I've used that technique for over 30 years to fix guitar fingerboards that have been chewed away by low frets and long fingernails. I mix in a little baking soda (maybe 10%) since the stuff sets much better in an alkaline environment. The baking soda also helps keep the patched area from getting darker than the rest of the wood (a consideration on maple).

I fill the missing area with the mixture and then drip a tiny amount of water-thin cyano off the edge of a scalpel blade (mixing the two ahead of time will usually leave a hardened mess to deal with). After the glue sets (almost instantly with the baking soda added), I use a fine file to bring the excess almost down to the level of the wood, followed by 400 grit wet-or-dry automotive finishing paper that I glue to a piece of Plexiglas (a flat stick works fine). It will never shrink, nor will it swell like some epoxies can.

 

[Sloppy Pockets]

This is a common practice for luthiers in filling gaps in bindings and inlay work and while repairing cracks. They usually apply the ca then sand the area immediately to mix dust from that piece of wood right into the glue. This technique has been used on many very very expensive instruments.

Heh, heh... just saw this after I posted. Yup, we luthiers have made an art form out of cyanoacrylate. Lol

Great for pearl inlay work, cracked fingerboards, binding, etc. I even have a special mix of baking soda and lampblack that I use for filling chips in unfinished ebony pieces (like fingerboards, tailpieces, violin bow frogs). It finishes to a nice matte appearance that looks just like the remaining ebony when rubbed with 0000 steel wool. Saved my tail on more occasions than I can count.

 

[TATE]

Heh, heh... just saw this after I posted. Yup, we luthiers have made an art form out of cyanoacrylate. Lol

Great for pearl inlay work, cracked fingerboards, binding, etc. I even have a special mix of baking soda and lampblack that I use for filling chips in unfinished ebony pieces (like fingerboards, tailpieces, violin bow frogs). It finishes to a nice matte appearance that looks just like the remaining ebony when rubbed with 0000 steel wool. Saved my tail on more occasions than I can count.

Man, I'm learning some new tricks!