This Martin guitar was left in a hot car causing the neck to pop loose, the back cracked, the top cracked, there were loose braces, and a few other things. It was really in bad shape and took a lot of work to get it back in playing condition. Hot cars are about the worst place to leave any music instrument. The ht air will cause glue joints to fail, wood to shrink and all sorts of terrible things.
It also warped the neck quite bad...
First step was to get out the hot tools and heat the neck off.
The cast iron tool is heating and placed on the fingerboard extension. This well help loosen up the glue joint and allow me to work some pallette knives under it. The foil you see is wrapped around some cardboard and helps to prevent heat damage to the top of the guitar.
Here I've almost got the whole joint loose. Luckily this guitars neck came loose quite easily.
Here it is with the neck removed. The heel of the neck had already come loose from when it was in the car, or else that would have to be separated as well.
Now that the neck is off, I will fix the split in the top.... I first re-humidified the guitar for a couple weeks to help close up the gap, before I glued it up.
This is a shot of when the top split is getting glued up. The top photo is some clamps and custom cauls I made just for this type of repair. It's important to have good clamping pressure and that its distributed over the whole area of the crack.
Once the crack has been glued, I then added some cleats, or small pieces of wood to reinforce the crack. The magnets are holding the piece of wood while it dries. Unfortunately I did not get a pic of what a cleat looks like, but it is basically a square piece of spruce that is tapered towards it's edges like a small pyramid...
After the crack repair, it was time to reinstall the neck. Here is a pic of it while the glue was drying.
After all was said and done. This guitar turned out really well. With that much heat damage sometimes guitars are never the same, this one however is playing as good as the day it was made....