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One application at a time.

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Peter Havriluk

Depending on the weather I will apply 3 to 6 coats in a day (Mohawk instrument lacquer), usually a session of three coats and later in the day another three if conditions are favorable. You want the first coat to be fairly dry before applying the next to avoid the top coat's surface drying faster than the coat under it (that causes "alligatoring"). I don't level sand between coats, but between one day's spraying and before the next I will "nib" or "scuff" sand the surface to remove any dust particles that are sticking up making the surface feel rough. I'll use a tack rag to remove the dust I've created and then I'm ready to spray the next day's coats. I'm not trying to remove finish, just smooth the surface so the next coat will lay flat.
Waterbourne and other types of finish may need a different schedule, which may allow more or less coats per day, so there is no "one size fits all" when it comes to finishing.

ok, back at it...or at least thinking about it. What I'm planning to do now is go ahead and mask off the underneck area and strip it back to bare wood first. That should let me measure the 'levelled' thickness of the original 16 coats which I'd like to know. Then mask that off and respray, which I feel like I should let cure for at least a week before I start any further levelling. I don't do any powered sanding, just the buffing. Since it's still moderately cool in the mornings (at 0900), I should be able to do that in the next coupla days without too much drama. If that goes well, I'll check in again when I start the level sanding. Planning to start again with 600. Thanks again for all your inputs. I'd be totally hamfisted and frustrated trying to figure it all out on my own. Roy

I think that plan is a lot of work for not much gain.

Frustration abounds.....Back to second guitar....I did a respray, didn't keep exact record this time, but seems like about three sprays all over. Started wet sanding after a couple weeks with 600 and 800. Haven't gone any further because I'm getting blushing that has me all out of sorts...couple/few pix ff.



The last one bothers me the most; I've used titebond to join plates on two retops and two full builds, and never had a problem with blushing along the joint line before. So now I have the third at binding, and am reluctant to go forward until I can figure out how to keep it from happening. So, yes I did use titebond in all these locations. Is covering all seams with shellac a reasonable solution?
If it matters, I sprayed lacquer in April, and we had not hit 100 degrees yet, although it was quite dry. I used a bit of retardant, which is not new to my process. Thanks for any advice. Roy

Barry, you were right, I did remove the finish under the neck, found the lacquer thickness was right at 0.010". Was a waste of time. Roy

That is not traditional blushing. I am pretty sure that is glue residue on the wood surface that is not getting removed during sanding stages. What this tells you is that you need to sand more. The back line could be a slightly open joint that is stuffed with glue, causing the same finish delamination.

One way to see glue residue during sanding it to wet the surface with a solvent (paint thinner or naptha). They also make a Titebond glue that glows under UV light when there are remains on the surface. I can usually see glue by wearing a magnified visor, plus knowing from experience where to look for it. Your photos show the typical areas to look for glue residue (all joints and the rosette).

The idea of using a shellac sealer would probably also be a solution.

Allright! Thanks, Barry, that makes a lot of sense. I don't feel all that comfortable that I really know what I'm doing with sanding, wet sanding, buffing, so it's clearly an area I should be able to improve. Is there any reasonable way to repair these areas? Roy

I am afraid the areas will need to be sanded down to wood and refinished.

Ok, I'm back at this guitar, wet sanding up to 1000, and it's looking better by far than numero uno. It's only my second guitar, and I've sanded thru a couple three spots at the binding edge, (again) so I'm gonna hafta respray focusing on the edges. My question is whether I should go after repairing the glue blush I show in the original pix. I might be interested in trying it if I really knew what I was doing, ie can I just sand back to wood in the areas I currently see blushing, mebbe coat with some shellac, then when I respray, mostly focus on trying to even the lacquer in the sanded areas to the original levelling? Honestly, I wouldn't be too upset to just finish this guitar as is to see how it sounds, and try to eliminate this problem on the next one, which has been sitting at binding for a couple months now. Appreciate any opinion sharing. Roy

You might be at the point where you just paint some finish on the "sand throughs", string it up and see how it sounds.
After you finish your next guitar, you can decide if you want to strip the finish off this one and do a better job of finishing it. Spot repairs are hard to do well especially when you have to remove the finish down to the wood in multiple places and then build it back up - better to just remove it all and start over.

I agree with Clay.

Just what I really wanted to do anyway, thanks!....uh, you mean paint with a brush? vs spot spray? And make sure I have a build-up that I can level? At least a coupla three coats...