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I was wondering if anyone had any strategies for brushing lacquer, specifically when it comes to the waists on the sides. I've been using waterbased lacquer, and it lays out wonderfully flat on the front and back of the instrument, but on any round overs and especially the contours on the sides the finish always wants to sag. I've mitigated it a bit by standing over it with a brush in hand catching any sags before the lacquer sets up, but it inevitably gets to a place where the lacquer skins over, but still wants to sag.

Which water based lacquer are you using?

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

I had the same problem when I was brushing varnish. I rotated the guitar until the varnish set, usually just a few minutes. I'd heard of builders using a rotiserrie for this problem and found one at a garage sale, but switched to FP shellac before I got around to setting it up.

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formerly known around here as burbank
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http://www.patfosterguitars.com

Brite-tone

That's kind of what I've settled on, it does help. Its just annoying that I have to babysit the guitar and can't really do anything else.

After posting yesterday I did try something a little different, I loaded my brush with much less product. I was always leery of putting too little on because a thin coat sets up and skins over so fast, and I've found I have to be extra careful about brush strokes. Also trying to catch a brush stroke that has already set up, I found its pretty easy to disturb the lacquer underneath. Anyway it seems like the right amount of product, moving swiftly and carefully it seems to work out well. I'll probably need to do at least twice as many coats as I was doing this way, but it's going on flat without having to deal with sags and heavy spots in between every application.

Your description in your original post sounds like the application may be too heavy. That's my interpretation if you are seeing sags and runs and you describe the finish as skinning over. Sounds like too much finish.

I haven't used Brite Tone, but I'm wondering if you need to use a retarder to increase the open time so you can brush on thin coats without them setting up too fast. I brush on EM6000 and for that using retarder is essential for it to work properly. Without retarder, the finish starts setting up almost immediately. For brushing on Enduro-var, it's also recommended to dilute it with water or a product called Extender to increase the open time. CrystaLac (Brite Tone) sells a retarder for use with their finishes, which for some reason I can't find on their website but is available on Amazon: https://www.amazon.com/CrystaLac-Viscosity-Retarder-Quart/dp/B002L347LW?ref_=ast_bbp_dp

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

I use Target EM6000. I usually spray, sanding halfway through the build and stopping around 12 coats. When I brush, I have found the secret is to use a very good brush—I have a 1” wide, flat sable hair brush—and to apply many very thin coats. Ideally, I load the brush lightly, brush in one direction, and don’t go back over it. Sometimes, an uneven application requires rebrushing, but since the coat is thin, reworking the surface doesn’t do much damage to he appearance when it’s dry. Every three coats or so, I level sand. The EM6000 burns into itself as it cures, so the many coats with level sanding still produces a uniform surface. If you see witness lines, you haven’t waited long enough for the cure. The secret is thin coats and patience.