Humidity, how much is to much

[CGHbuilder86]

I am about to start spraying nitro lacquer on my latest project and I would just like to know how much humidity is to much. I always add a little retarder to my lacquers so that they dry slower and spray a little better. I am already familiar with how the temps need to be, I was just needing to no about humidity.

[AlGeeEater]

I think that 60% humidity is the limit for me. Even if it is 60 percent i aint going to spray becuase the paint seems to mess up. I really wait till its around 40 percent or 30.

Just a little guidline

Edited September 18, 2004 by AlGeeEater

[unclej]

what AlGeeEater said...50% is what i look for to insure no clouding and that the paint will lay down properly.

[CGHbuilder86]

Thanks guys, I won’t spray if its over 50%

[AlGeeEater]

If you get 0% humidity you better drop everythign and start spraying.

[johnsilver]

How much does humidity matter if you are spraying water base lacquer?

[Mickguard]

I'm bringing this one back up rather than starting a whole new thread.

I converted part of my office into a spray booth (i.e., I hung a bunch of plastic sheeting in one area-- obviously I'm not working in there for the duration!). I'm keeping the place heated for the while.

I started spraying a couple of days ago, using nitro in aerosol cans --so far I've done the sealer coats and the first round of clear coats (4 coats so far). I have to say this stuff is great, much easier to work with than the acrylic automotive cans I'd been using. I have another day of shooting --I'm planning on another 4-6 coats, in order to keep the finish pretty thin.

Problem is--it's raining today. And since this is the west of France, there's no telling when the rain will end--could go on for a week, or a month. I'd like to be able to work in there again before the end of the week (the guitar will be hung to dry somewhere else).

My question: since I'm spraying inside, and it's dry inside, can I still spray with no issues from the outdoor humidity?

[AlGeeEater]

I think your best bet is to get a little indoor humidity gauge (I think they're called Hygrometers?) at let it sit in the office for an hour. They're pretty accurate, but i'd say you shouldn't have any problems from outside humidity.

Chris

[Mickguard]

I think your best bet is to get a little indoor humidity gauge (I think they're called Hygrometers?) at let it sit in the office for an hour. They're pretty accurate, but i'd say you shouldn't have any problems from outside humidity.

Chris

Well I got lucky today...sun came out nice and strong, everything was dried up by noon, so I had no problems spraying.

[menaceg]

I started spraying a couple of days ago, using nitro in aerosol cans --so far I've done the sealer coats and the first round of clear coats (4 coats so far). I have to say this stuff is great, much easier to work with than the acrylic automotive cans I'd been using.

Easyer in what way? I am using acrylic lac and from a gun. I am always looking for a better way. IS the dry time different?

[Mickguard]

I started spraying a couple of days ago, using nitro in aerosol cans --so far I've done the sealer coats and the first round of clear coats (4 coats so far). I have to say this stuff is great, much easier to work with than the acrylic automotive cans I'd been using.

Easyer in what way? I am using acrylic lac and from a gun. I am always looking for a better way. IS the dry time different?

Part of it is in the quality of the aerosol--the stuff I found seems to have a much more consistent pressure coming out, so it just sprays more evenly. Could be that there's a better nozzle on the can too?

But mostly it's just the way the solvents in the nitro react with the existing coats--the new coat seems to blend in pretty almost instantly, without even coming close to giving me a run or sag or drip. With the automotive acyrlic I used, it seemed like there was more of a lag time for when the solvent would break into the existing coats, and I had more trouble with getting things consistent.

Also, even though there's still some orange peel with the nitro (I gather that's to be expected from using spray cans) it's very fine, much finer than I had with the acrylic cans.

I think the nitro is nastier to work with though-- I have a respirator, but I resorted to wearing a diving mask AND swim goggles while spraying too.

We'll see what it's like wet-sanding and polishing...right now the body's hanging up in a heated bathroom.

Still, once I've used up this supply of cans (I have enough for another guitar), I think I'll pick up a compressor and spray gun finally.