Can this scratch be fixed?

[JackB1]

Put a nice scratch on my Martin last night
Anyone know if this can be fixed? Would need to be sanded and refinished with the gloss. So bummed!

[tadol]

It’d never be perfect - but it should get sealed so dirt and polish doesn’t get into the wood grain and discolor it, making it even more obvious -

[fazool]

finishing is an art and easily done wrong.

nitro is pretty forgiving but have a pro do it.

[mirwa]

It needs to be lightly sanded to remove the torn sections of grain, then a bit of further alignment with a razor blade if required.

Contrary to peoples thoughts, a gloss finish, patch repaired cannot be made invisible, it can look really really good but not invisible, to become invisible you need to clear coat the whole top otherwise you end up with transition lines in the clear coat between the new and old finish.

Steve

[John Arnold]

Invisible spot repairs can be done in nitro lacquer, if the proper technique is followed. You cannot just overspray with lacquer and expect no witness lines. That is because the solvents in lacquer formulated for spraying evaporate too quickly to 'melt in' with the old lacquer. The old lacquer must be softened with retarder first, in order to create a chemical bond.

[JackB1]

How exactly is that done?

Originally Posted by tadol

It’d never be perfect - but it should get sealed so dirt and polish doesn’t get into the wood grain and discolor it, making it even more obvious -

[printer2]

How about steaming the damaged fibers?

[phavriluk]

OP seems interested in getting an invisible repair. And that's not going to happen except by an experienced professional. For sure I'd not be planning on practicing something I've never done before on an instrument whose value can be cut in half by a poor repair. And any repair I do for the first time, climbing the learning curve, won't be on a high-end must-be-right instrument.

[mirwa]

Originally Posted by John Arnold

Invisible spot repairs can be done in nitro lacquer, if the proper technique is followed. You cannot just overspray with lacquer and expect no witness lines. That is because the solvents in lacquer formulated for spraying evaporate too quickly to 'melt in' with the old lacquer. The old lacquer must be softened with retarder first, in order to create a chemical bond.

Totally dis-agree with your statement "invisible spot repairs can be done in nitro lacquer".

Every finish medium has a different reflection and refraction ratio, you may have some nitro to touch up say this guitar, but you wont have the same nitro formulation Martin used that week on that guitar, so any touch up will diffuse the light differently and in turn stand out.

Steve

[John Arnold]

That has not been my experience.

[mirwa]

A lot of my work is warranty work, these are high gloss finishes where a customer has commented about a small white sliver in the new guitar around some binding or a bit of a dimple in the clear coat when you hold it to the light, or my favourite, its got these fine scratches which show really badly when I hold it like this.

Steve

[Mr. Jelly]

I could be wrong but I thought I saw a Stewart MacDonald video on repairing old solid body guitars with such issues.

[JackB1]

Can you explain?

Originally Posted by printer2

How about steaming the damaged fibers?

[rmp]

been there, I know the pain. Similar scar on my Taylor from a mic hitting it

I sent it back to Taylor directly, and they did an amazing job.

(I have b4 and after photos if you're interested.)

Not sure if Martin would provide the same service, it wasn't cheap and it was gone for 9 weeks, shipping it TO Cali was brutal cost wise, but this was on my 2006 Grand symphony, to me it was worth it.

[John Arnold]

Steaming works really well when it is a 'soft' dent that is rounded, with no damaged fibers. It is difficult to tell whether this scratch is in the finish, or actually cut through wood fibers. If it is the latter, an invisible repair is generally not possible without sanding the wood.
I would first attempt to melt the damaged finish with retarder, just to see if it will improve the looks (very likely). If that seems sufficient, I would just drop fill it and call it good.
The main problem I run into when matching lacquer finish does not involve a difference in the refractive or reflective quality. It is when the wood itself is sanded, exposing new wood that is not oxidized. This is particularly true on spruce tops, Sitka being the one spruce that darkens the most on exposure.