MIMF

Hello guys. In the process of sanding/polishing the finish, this guitar took a bump and some of the finish (PU) cracked and became separated from the top. As it's hardwood top and binding, there is no dent, and the crack itself is barely visible and not palpable, then my first idea to simply inject some CA glue on the crack seems unplausible.

Any ideas are welcome.

Here's the picture.

If it is not through the full thickness of the finish - and given that it is such a small area - you would probably get away with just sanding and buffing it out. Watch this video by Dan Erlewine to learn the strip sanding technique (at the end of the video).
https://www.stewmac.com/video-and-ideas ... inish.html
If you think it is through the full thickness of the finish then you will need to drop fill. You could use CA glue or PU (if you know that to be the finish - but it is more likely to leave some witness lines).
cheers
mm

I would definitely try some water thin CA glue. It might seep in and make it disappear. Not much to lose trying this. When you put the CA on, if it does not seep in all the way, wipe off the surface then press on the area with your finger to try to pump the CA a bit more.

Mark, it's not a chip, but more like an Air bubble under the finish. The surface of the finish feels intact. Anyways there's good advice on the vídeo.

Barry, I'll try to inject some CA with a needle and a syringe.

I might skip the wood sealer on the next PU finish...

You don't want to inject the CA. That could lead to it squirting everywhere. Place small drops on the open fracture and let it seep in. Try not to get glue on the entire length of the fracture as that will seal it off and prevent the air from escaping, which it must do in order to allow the CA to penetrate fully.

Barry, I've followed your advice and it worked nicely. Thank you again.

Nice.