Vintage Guitar Crazing

[mairj40]

I just picked up an old Espana acoustic guitar. The guy I bought it from said that it was his fathers. It is not in too bad of shape. The biggest thing is that it has a ton of crazing on the top. Is there any way to fix this without sanding it down to bare wood? I have sanded acoustics down and refinished them before, but this guitar is pretty cool looking (aside from the crazing). Or should I just leave it? It is the top of the line that Espana made. I see them for sale on Reverb for $200 to $375. I only paid $25 for it, so it isn't a huge deal if it needs to stay the way it is. But, I'd like to make it look as good as possible.

[Aubade Acoustics]

Paste strippers are the safest in my opinion to remove the finish. Might not be the best for your health but sanding the finish off you risk making the top thinner in some spots. Leave it like it is. Nothing wrong with checking.

[Hot Vibrato]

Originally Posted by Aubade Acoustics

Nothing wrong with checking.

I agree. I like the way my vintage guitars have checked. Wouldn't change them if I could.

[B. Howard]

Crazing and checking can be repaired without re-finishing. It involves carefully and slowly re-hydrating the original lacquer with solvents and then after 4-6 weeks you can re-buff and it will look like new except for the amber color that it has developed over the years.

[mairj40]

Originally Posted by B. Howard

Crazing and checking can be repaired without re-finishing. It involves carefully and slowly re-hydrating the original lacquer with solvents and then after 4-6 weeks you can re-buff and it will look like new except for the amber color that it has developed over the years.

What type of solvent? Lacquer thinner?

Not sure I am going to mess with it, but I am curious about the process.

[Hot Vibrato]

Originally Posted by B. Howard

Crazing and checking can be repaired without re-finishing. It involves carefully and slowly re-hydrating the original lacquer with solvents and then after 4-6 weeks you can re-buff and it will look like new except for the amber color that it has developed over the years.

I would love to hear more about this too.

[Rodger Knox]

Yeah Brian, you and who else in the country can do this? Maybe 10 or 12 people.
It's certainly not something that most people would be able to do, but you don't really have anything to lose by trying. You can always strip it off and refinish it.

I'd leave it alone, I really like nice even crazing on a vintage guitar.

[SMan]

Originally Posted by Rodger Knox

I'd leave it alone, I really like nice even crazing on a vintage guitar.

That's what I'd do.

[mairj40]

Here's some pictures...

[Bruce Sexauer]

What a beautiful color tone! Don't mess with fate!

[redir]

I would not touch it but you are going to need to fix that bridge pin hole.

[mairj40]

Originally Posted by redir

I would not touch it but you are going to need to fix that bridge pin hole.

Yeah, I think I am going to leave it alone.

The bridge was off when I got it. It's strange because when I looked in the soundhole with a mirror, there was no plate under the bridge. In fact, it didn't look there had ever been a plate glued in place there.

I made a small bridge plate to go under the bridge inside the guitar. Hopefully that will help strengthen it up a bit.

[B. Howard]

Typically not just a straight thinner.....But I only use hardware store thinner for cleanup. All my spray reducers are Are graded by temp range or speed of evaporation and I am sure that none contain recycled solvents of any kind. That last part is surprisingly important.....

But back to the process. Cleanliness is the most important thing! Waxes, grease, silicone and just plain old dirt will ruin the finish to where strip and re-finish is the only option. Start with a rag and naptha followed by good ole soap and water. I use a soft tooth brush with the bristles cut down to gently scrub all the crazing.

Leave this dry very well and inspect carefully. Any missing bits of finish will need filled and left to dry about a week at this point.

I use a heavier, slower solvent, not something available OTC, which would be similar to a blend of slow reducer and a bit of retarder. This is then sprayed onto the surface with my gun and a 1.0 tip. I apply one wet coat and wait a minute....then I begin misting the surface lightly to keep it damp. Be very careful as there is a delayed reaction.......the finish film will continue to soften after the solvent has flashed. There is a fine line to be walked here, you need to make it wet enough to re-flow and re-bond but make it too wet and it will run.

This must be kept dust free for a few hours and left to re-cure for several weeks before any polishing.

[Aubade Acoustics]

The problem I have run into with melting the finish to blend the cracks is they tend to have dirt and dust in them and it is difficult to remove. They still tend to show up and eventually ghost back because more of the solvent used ends up in the cracks when padding. Not saying it cannot be done, just a lot of work and experience needed before taking on a project like this. Nice color on the top.

[Ned Milburn]

There is a Mohawk product I have seen that is similar to what Brian mentioned, a weak solvent based product. Spray on, and hope it seals the crazing cracks.

But as others state, it is a can of worms, without guaranteed results.