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I'm in the midst of finishing my first guitar right now. I put down a wash coat, grain filler, another wash coat, and then began lacquering. I'm using aerosol nitro lacquer, btw. I first put on a thin tack coat and then two wet coats. I sanded with 320 grit, and put 3 more wet coats on. I sanded with 400 grit and put 2 more wet coats on which are currently drying. At this point, I have a general plan on how I'm going to finish things up, but need a little bit of help with some details. After this coat is dry, I'm planning to sand with 600 grit and then add a final two coats. I've been able to keep my coats acceptably level, but occasionally I have kind of a burp from the aerosol can and I'll get a small bubble or dot on the finish. This hasn't been a problem thus far since I've been able to sand these imperfections out, but I'm worried about what to do if this occurs while putting the final coat on. I'm not sure if this is right, but I'm operating under the assumption that I do not sand after the final coat before leaving it to cure. I haven't been able to find detailed enough info regarding this sort of thing, but maybe I do sand after the final coat? I'm planning on after the cure period to sand with 1200 grit and then polish to a high gloss. I'm sorry if my story here is a bit convoluted, but can anyone offer me any advice? I just want to make sure I have no bubbles in the end. That would just be awful. Maybe there's a trick to get the can to not burp? Any help here is appreciated!

PS - These may be dumb questions, but I suppose the whole finishing process has made me just a bit nervous. Please don't think too lowly of me!

That'll work just fine. Make sure to let cure for at least 2 weeks, if not a full month if you can. You'll notice your small bubbles will be greatly reduced by the lacquer shrinkage while curing. You might want to use 800 grit just on the spots where you have bubbles or any imperfections to smooth out prior to overall sanding with 1200.

Nope!

_________________
Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

What Alain said- lots of curing time helps a lot and makes sanding easier and more effective.

The fact that it's warm where you are will help!

My problem with nitro- especially at first- was putting on too much, but you seem to have that under control. If you haven't sanded through, you are doing a lot better than I did at first!
Cheers
John

Minor bumps in the final coat won't be a problem. They'll level themselves alot while curing. I recommend at least 4 weeks between the final coat, and buffing. Lacquer shrinks for a long time. I use one of these for runs, or really bad spots. http://www.autobodytoolmart.com/search/search.aspx?keywords=run+razor

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

Not that I would ever do this but I've known of some people who "warm" their spray cans of lacquer in hot water before spraying. I've "heard" that you get a real nice even flow. I can't recommend this procedure as the contents of the can are under some pressure. I only know of rumors that it's been done before.

I finished my first 6 guitars with aerosol lacquer and got some good results too. No matter what I did though the last 1/3 of a can always started spitting or was inconsistent in laying down the material. I tried warming the cans as described above and it did not help me with the Stew-Mac lacquer that I was using.

When I just decided to stop with 1/3 of a can left and go to a new can my results improved. Also tipping these cans at all is asking for a drip or spit to happen.

Here's a pic of the results that I had with Stew-Mac aerosol lacquer:



All I did was follow the finishing schedule listed in Stew-Mac's free-for-download dread guitar kit instructions.

Great info, thanks for the help guys!

Great info, thanks for the help guys!