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Is anyone spraying nitro outdoors with any success? I have yet to spray any finish and am getting tired of brushing. I’ve been thinking about getting set up to spray waterbornes but am toying with the idea of spraying nitro instead. With my current facilities the only way I could do that is to spray outdoors.

Does anyone else spray nitro outdoors? If so, what challenges have you encountered? Do you just spray in the open or use some kind of enclosure? I live in a relatively dry climate so humidity is not typically an issue. I know wind can be a problem while spraying but since nitro skins over pretty quickly I’m hoping I would be OK if I spray mornings and evenings.

I would appreciate any thoughts, tips, experiences, etc. Thanks.

When I did this outdoors I learned a few things and will pass this on
Direct sunlight can over heat and bubble things. Bugs LOVE lacquer and I swear every tree , shrub and bush will emit pollen the moment you hit the spray .
Go to walmart and get a plastic hanging wardrobe . They are not that expensive . The one I used had a nice plastic zipper. I would hang this off the wash line. I could hang my body in it . I had it so I could turn it. To avoid wind gusts from making things unsecured cut 2 cardboard squares that can keep things from touching the guitar. Spray. zipper closed then respray . I used them for about 3 guitars.
If it is sunny and warm you may want to cut a vent hole , I did that between the card board and the top. This allowed the hot air out so it wouldn't bubble the finish.
Some heat up to about 125 F is actually ok

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I used to shoot nitro outside, too. I would just open the door, walk out and spray, then duck back inside and hang the instrument. It worked fine, but....!! The freshly sprayed instruments keep off-gassing for weeks, and this is how I became sensitized to nitro lacquer. If you have a small fan in your workshop, hang the parts near it, and keep it running at least for the first full day, and a 1/2 hour a day for the next week if it's a closed space. If you build in your home, forgetabout it; the risks are too serious.

Bottom line, you can spray outdoors, but you shouldn't be "curing" the lacquered pieces in your home. If you have a shed, garage, anything, hang it in there, and you'll be fine. Maybe something like John says, or even a dog house.... Anything but your home!

Edit to add, the bugs and dust really weren't a problem for me. The surface skins-over so quickly that even the bugs that did get caught in the finish weren't dug-in so deeply that they ruined it; they'd sand right off in the leveling stages. I have always shot nitro in many "dry" coats, meaning, thin, quick coats, instead of a few heavy wet coats.

I spray outdoors all the time. John's advice is spot on, however, I do without the wardrobe. I hang my bodies and necks off of the frame for a wooden swing that hangs in my yard. I make certain it is out in the open, away from too many trees. The nitro skims over fast enough that usually anything that hits it doesn't stick very often. If it does and it is small, you can carefully remove it and then just continue to spray over it. I've leveled the finish after all the coats are laid down and it has cured for 4 or 5 weeks, and the defects have all dissappeared.
If it's something large, like a big bug, wait a few days, sand the defect out, and start laying down finish again. Them's the breaks when spraying outdoors.
One other thing I do is keep a close watch on the coats until they stop being tacky. If you catch whatever it is while the coat is still wet, I've often had the lacquer flow out and the defect dissappear on it's own.
Also, at least here in Virginia, it has been my experience that spraying late in the evening is the worst time for blush. I usually stop spraying when it begins to cool down(6-6:30). Don't know about mornings, as I never start before 9 a.m.
As far as spraying in the sun, I do it a lot, and have for the past 4-5 years. I've had no issues with bubbling of the finish, but I lay on very thin coats. 3 thin passes for me is 1 coat. That may have something to do with it. I also at this point use aerosol lacquer, which I warm in hot water before spraying, which may mitigate that as well. I plan to purchase a compressor and proper spray equipment this year.
This was shot outdoors using aerosol lacquer.



This was shot outside with automotive lacquer.




spraying outside can work well. I say go for it.
P.S. : Grumpy is right. Nitro fumes are highly toxic. If you value the health of yourself and your family, do not let it cure in your home. I hang mine in the shed out back for a minimum of 4 weeks.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

Now it all makes sense! I wish you guys would stop spraying outdoors. The pollen is killing my allergies!

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http://www.CostaGuitars.com
PMoMC

Spraying outdoors will work - watch for the bugs and any windborne crud.
It's much better than where I started back in the 70's.... in the milking stall of a dirt-floored barn!

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"Act your age, not your shoe size" - Prince

As long as the air is still perhaps, personally I find nothing more annoying and counter productive than trying to spray a nice coating in a variable and changing cross wind, and then there is the dirt........ Though John's wardrobe thing sounds like a good cure for some of that. Painted a car or two over the years in a big tent and a few motorcycle sets hanging on my washline, not any of my best work.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Not to mention a flash rainstorm....

Thanks to everyone for the replies! I'm encouraged.

John - the hanging wardrobe and cardboard sounds great. Thanks for the suggestion.

Mike - that is some fine looking work! Rattle cans, eh? Who'd of thunk...

Mario - thanks for the warnings about curing in the house. I'll have to come up with a protected place to hang my work well away from the house.

Tony - I will try to hold off on spraying outdoors until summertime when the pollen counts are much lower.

Would still appreciate any other advice, wisdom or tried and tested methods....

One way is to spray the work "flat" on a table and cover it with a large cardboard box. To do this place supports in the bridge area and the fingerboard extension area. Spray the top heavy and the sides lightly, allow the lacquer to flash off, then flip the guitar over on to the supports. Then spray the back heavy and the sides lightly again and allow to dry. Two light coats on the sides for every heavy coat on the top and bottom seems to give about the same build.

Clay – that’s a great idea for preventing runs. How long do you let it flash off before flipping and spraying the other side (and sides again)?

Todd – I know you use a drying box – is yours inside our outside? Thinking of building one but mine would have to be outside. Thanks for the squirrel warning - we have a lot of them here.

Thanks guys!

I work in my garage with the overhead door open. Depending on the wind I spray nitro just inside the garage or out front. If there is any question of blush I try to get the guitar slightly warm. The sun works for this, also a big dual halogen work light as long as I am very careful to not overheat the guitar. When it is really cold out I have the guitar inside by a furnace vent while I get the gun loaded outside. As soon as I bring the guitar out I start spraying. I've had no problems down to the mid thirties, once I learned to shine a work light on the gun itself starting ten minutes before I put the lacquer in it, then let the light warm the lacquer in the gun gently. Gibson (and furniture factories) used to lay down just one coat of hot lacquer with almost no thinner.
Incidentally, the open sky bouncing off a flat guitar surface to you eyes makes it easy to see when you are laying down a good gloss.
Don't leave a guitar in the sun until the lacquer stops being smelly (1-3 days). It can bubble up!

Leonard – thanks for the ideas on heating the gun, lacquer and guitar. The idea of laying down fewer but thicker coats on horizontal surfaces is appealing. Is there any danger of solvent pop or other maladies with laying down thick coats like that?

Good thought on the reflection of the sky in the horizontal surfaces, too.

I sprayed nitro in effect 'outside' for about 15 years, and I only recently got a proper spray booth (what a relief). It was actually a shed next to my garage, where I would open the doors when I sprayed, and leave the instruments hanging until the lacquer had cured. The biggest problems in this part of the world was the orange peel effect in the winter, and blushing from trapped moisture during humid conditions in the summer. I would avoid too thick layers, as it would make both these problems worse.

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Rian Gitar og Mandolin

I often hang guitars on the porch to out-gas. The problem here is swallows. The youngsters will rip across the creek, into the soundhole, tumble turn and back out again without touching the guitar. I've even had one fly into the workshop and do the same thing. A feat of aerobatics that not even Todd could pull off...

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

I made a quick wood frame and threw one of those blue tarps over it. It is fully open on each end and closed on the sides. It seems to keep most of the junk off.

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Michael F Smith
Goat Rock Ukulele
http://goatrockukulele.com

Hi Charlie,
Flashing off can be anywhere from 10 minutes to 1/2 an hour depending on how much the lacquer is thinned and the environmental conditions.
I've been spraying unthinned Mohawk lacquer for the most part and my "heavy coat " is about the same as I would do on a horizontal surface for a cabinet. A good "wet" looking surface, but nothing that would run and puddle. The sides are sprayed much as you would for "double coating" that some finishers do - spraying a light coat, allowing it to flash off a bit ,then spraying another light coat. Allowing the quickly evaporating diluting solvents (xylene, toluene, etc.) to leave, then spraying a second light coat reduces the solvent ratio in the (double)coat and allows the lacquer to "hang" better. The diluting solvents are used just to "thin" the lacquer to make it spray nice. The (for the most part)slower drying dissolving solvents remain longer to help the lacquer level out better (reducing "orange peel")

A friend of mine suggest this to me and I think it is actually a great idea.

A large refrigerator box makes a great outdoor spray booth.. The key is to protect the fish surface from contamination.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Thanks for the info, guys. Much appreciated.