Needing Help Fixing A Crack In Lacquer.

[J_48_Johnson]

I put down too many coats too heavy on my headstock and the lacquer cracked after a few weeks of cure time.

I mixed lacquer and thinner at a 50% - 50% ratio to drop fill into the crack. Right/wrong?

Is there anything I need to do before starting?

Give me some tips so I don't mess this up any further.

This is my first build so these problems are expected. I'm learning what NOT to do on the next build along the way but any help is apprecieated.

[westhemann]

man,i really don't know for sure so i am just talking out of my ass here...but laquer has a 100% burn in between coats,so i think that is how you normally would do it...

BUT the last time i sprayed laquer too thick,it cracked a little bit at first,but then like 6 months later it really went crazy...now it is cracked over the entire body....if it is just your headstock that is a very small area,so i would just sand it down and redo it with thinner coats

[Southpa]

I was going to post a reply to your post in the tele forum saying , "ask at Projectguitar", and here you are. Is it actual cracks? or "crazing"? Around here a picture is worth more than 1000 words. Got any?

[J_48_Johnson]

Here's a picture of the problem:

As you can see there is a crack in the shape of the Nike "Swoosh" above the artwork. I have started working on it by making a 50 - 50 mixture of lacquer and lacquer thinner and drop filled it into the crack. I can see that it has melted into the lacquer because the crack is now wider and not so deep. It is starting to fill the area in. I then let it dry and drop filled some grain filler into the remaining crack and it has been drying since last yesterday evening. I may give it until tomorrow to dry before sanding flat and putting a THIN coat of lacquer on it to level back up. After this I should be on my way! (I hope).

Any help on this would be great! Am I going about this the right way? It seems to be working... so far.

[Sand Paper]

I'd think that adding more material might compound the problem. It won't be level either so you'd have to do some sanding anyway. I've never actualy tried this but it might work, some of you may have done this and know the result, i'm just speculating here. You could try spraying 100% thinner onto it in multiple coats and see if it doesnt soften up enough to flow back togeather and seal that crack. This would also open up the top layer and possibly aid in curing up the undercoats. I may be onto something, i'm probably wrong though, i've never experienced a cracking finish.

Edit: I didnt read the post with the picture in it, i just looked at the picture. So maybe i'll try my method out if i ever run into a cracking finish.

Edited January 23, 2007 by Sand Paper

[J_48_Johnson]

Two coats of a lacquer and lacquer thinner mixed 50-50 drying in between drop fills, then two coats of grain filler to fill in what was left. After the first coat I could see that the crack had widened and was shallower because of the lacquer melting and filling in. After the secons coat I could see a rounded bottom trough. First coat of grain filler was standing high above the crack when I drop filled it. After it dried it was lower in the middle so I drop filled it again the same way. Adding too much made it way high but as it dried it shrunk back to a bit of a hump where the crack used to be.

Here is the headstock after filling and block sanding smooth.

After it was sanded, I shot one coat of lacquer on it to see what I had. The crack went from a very visable white line to an almost clear ghost of a line. I'm keeping it.