Repair of Alvarez Yairi DY57 Acoustic Guitar

[johnnparchem]

A friend of mine (a professional bass player) tripped over his knock around guitar and cracked the neck right off. I do not think these are worth a fortune but he did like the guitar. When I looked at it, I though I could quickly get it in playable condition but I thought I would run my plan by you guys to set me straight. He does know that the repair will be visible.

Although it looks bad, I have the pieces and can put them back together and keep the neck alignment in place. Looking at his saddle perhaps improve it.





My thought is to clean up the old glue on the poor glue job on the neck block extension, I can tell only part of it was joined, and reglue it and the broken heal block with a structural epoxy. I would use fish glue or titebond hide glue to put the top back together. I thought of using hot hide glue but I really want the open time to get every into position as it is a 3D puzzle piece to fit in. Both the fish glue and the titebond hide glue are cleanable.

Once in and clamped (no glue yet) It looks like I can do a reasonable job of keeping things in alignment with the same neck angle.

[johnnparchem]

I thought through a few of the options but discarded most because I just could not put the time in it. I found nice used versions of this guitar for about $500. I did decide that I was not going to give it back without a decent bit of saddle showing at a good action. I kept with my decision to use structural epoxy for the neck block and I used titebond hide glue for all of the non structural work. Both gave me a decent amount of working time to get things right. I mocked all of the clamps and played until I was able to have a straight edge from the first fret to the current short saddle with an action of about 1 mm. I use the first fret instead of the nut as it results in an action that is closer to the result when strung up. Anyway my reasoning was that going from 1 mm to 2.5 mm of action would add 3 mm to the saddle. Part of the damage when the neck broke off was a missing wedge of mahogany just at the transition to the heel. That missing piece was enough that even when all clamped up the weight of the head stock and tuners pulled the neck back a touch and gave me the exact neck angle I wanted. Here is the saddle with 2.5 mm action for the low e. The E string is 12.5 mm off the top. The action could be lowered to 2 mm if he wants.



To illustrate, I actually switched to a straight edge when I checked it for the real glue up.






Here is where the wood was missing I already filled it with a mahogany patch and have started finish repair




I never promised an invisible repair, the guitar has plenty of scratches and pick gouges so it was not too hard to do a repair that sort of blended in. Well at least the guitar really plays well.

[tippie53]

that was a great pulled off repair. well executed.
You Dun Gooood