Nitrocellulose Clear Coat Cloudy

[brokebymonday]

I'm having a strange thing happen as I'm spraying the nitro clear.  It's becoming cloudy and splotchy.  Has anyone encountered this before? :rock-on:

 

[bagman67]

Sounds like what they call "blush" in the industry.  If you spray when it's humid, the moisture in the air will sometimes condense in your spray cloud, and end up trapped in your clearcoat.


If you're working out of rattle-cans, you cannot do anything with the product you're spraying.  If you are mixing your own, you can add retarder to your mix to slow down the lacquer's curing, and improve the chances that the moisture will evaporate off the surface.  In either case, you can also shoot the coated surface with something called "blush remover," which essentially melts the finish again so the moisture can evaporate.  If you want to go super-ghetto, you can also just try shooting the surface with a mist of lacquer thinner to flow the coating enough to maybe make it release the moisture.


http://www.woodcraft.com/Product/811454/(H)-Jet-Spray-Blush-Eraser.aspx?gclid=Cj0KEQjwvJqvBRCL77m2-uKczsIBEiQAkx8VjFkV_EgoWP3V8FK7kbQXQ2FywjXFWVbqVajvHLORq-kaAtYe8P8HAQ

 

[Cagey]

If you want to go super-ghetto, you can also just try shooting the surface with a mist of lacquer thinner to flow the coating enough to maybe make it release the moisture.

Yep. Blush. Too humid.

However, unless there's some trick I'm not aware of, shooting straight acetone at a lacquer finish changes its name to "Paint Remover".

 

[bagman67]

Yeah, well, that's why it's "super ghetto."  It may be worse than the original problem you set out to solve.

 

[Cagey]

Indeed.

I did it once, thinking I could flow out some orange peel. It was like watching a time-lapse film of a rotting corpse. It went from relatively smooth to all wrinkled, blistered, snotty mess with layers sliding off in less than a minute. Talk about ugly.

On the plus side, I found out how easy it is to strip lacquer-finished guitars. Unfortunately, few guitars are lacquer finished these days - most OEMs shoot poly. You can shoot acetone at poly all day long and it just laughs at you.

 

[dmraco]

I had a case of blush once.  I sanded most of it out, then strayed the next few layers of nitro with a little EXTRA thinner. 

Spray the coast thin to avoid runs.

They do sell "blush remover" but i have never used it.

How long have you let it dry?

 

[brokebymonday]

When it first happened, i thought it was all because of the color.  I sanded it back to primer coat, then sprayed more color.  I'm following the stew-mac book on finishing, so i'm putting the clear on thin, letting it dry for 30 min then another coat. 4 coats per day.  It's blushing bad so i figured it was the clear.... i'm hoping it'll polish out after a wet sand

 

[Tonar8352]

Your finish is flashing off to fast, acetone is way to hot meaning it flashes of a soon as it hits the surface, forget using that stuff.

I do not know what lacquer you are using but the best cure for the lacquers I use is to thin it with additional lacquer retarder. It allows the surface to stay open longer and then the moister will be able to escape before it gets locked in.

 

[brokebymonday]

i think i've fixed the problem, supremely thin coats, working out well.

 

[brokebymonday]

every photo i took was shaky, i'll post the feeneesh product soon

 

[Tonar8352]

Looks good so far!

 

[pabloman]

Do you have a water separator on your air lines?

 

[dmraco]

I do not know what lacquer you are using but the best cure for the lacquers I use is to thin it with additional lacquer retarder. It allows the surface to stay open longer and then the moister will be able to escape before it gets locked in.

what do you use and in what ratio??

 

[brokebymonday]

i just used the canned aerosol.

 

[brokebymonday]

not wet sanded, not polished. clear coat on and lets see if this thang works ccasion14:

 

[brokebymonday]

Lemme know what you guys think

 

[Cagey]

It's tough to tell anything about the finish due to the poor quality of the photos, but it's certainly an attractive color.

If those were shot by an iPhone or something, you should be aware that most cellphone sensor sensitivity is less than ideal by a long shot. You need really good light to get good shots. Even a cloudy day is better than indoor light or flashes.

 

[brokebymonday]

rookie photo taker

 

[dmraco]

so far I like what you have put together.  Color is cool.