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Hey all,
I've been working on a side-by-side build with two guitars since September. They're finally ready for finish, but the weather in Minnesota isn't helping much.

After searching through the archives and the Target Coatings site, I've not been able to find good data on how cold is too cold to spray Water based lacquer. I've got a gallon of Target's USL waiting to go on these instruments and it is driving me nutz to just let them hang until the temps come up.

thanks to anyone with advice.


Dave

I don't know about Target specifically but I'd say you want it to be 60 degrees to spray any finish. I assume you'll be spraying either outside or in an unheated area. Maybe you could spray it when its cooler by heating the finish in the gun to 120F or so. My views aren't based on actual experience with cold finishing. I have access to a state of the art automotive spray booth so I've never sprayed in cold conditions.

Added: Try spraying some scrap wood and see how it works.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

Thanks woody.

I should have mentioned that I spray in a plastic bubble I constructed in my unheated garage.
(Fumes are vented via a squirrel cage I took off an old furnace)

Call the folks at Target. They're very friendly and helpful.

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Steve Smith
"Music is what feelings sound like"

I've sprayed nitro lacquer in cold conditions. One thing I will relate is do not spray if it gets below freezing. That was my break point.

62f per Target's spec if I recall correctly. this is a prety common min temp for waterborn coatings

I use a similar setup in the basement and find that the finish sprays well above 60 deg but when it is warmer the spray flows onto the surface better. Those old furnace squirrel cages work great as an exhaust fan if I start it well before I spray the odors of the lacquer are not even noticed up stairs, but the back yard sure does.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

You might consider investing in some kind of portable heater. Years ago I heater my (poorly insulated) 24' X 30' race car shop with a 65000 btu forced air kerosene heater. I could turn the heater on and have a comfortable shop in less than 1/2 hour. It's not super cold here in NC. I'm not sure what BTU you'd need up there. Google "portable forced air heater". They've available for kerosene, diesel or propane. Since you're using a water based finish the heater (which uses a flame) wouldn't be a problem. I wouldn't use this type heater with nitro or other solvent based finishes. I painted a few cars with nitro using it, and a couple box fans under the garage door but looking back I believe I was lucky I didn't have a fire or explosion.

_________________
I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

Knowing that the answer to life the universe and everything is 42, I would think it a good number to use.
It must be the minimum because I couldn't take it any longer and sprayed all day today and it only got to 55 in the garage.
I did keep everything in the house until the moment when everything was set and ready to go. Then I had the wife shuttle necks and bodies from the basement out to the spray gun. And when I was done with each session, the gun went in the house too.
It was probably overkill on being carefull, but I wanted it all to work out.

The five sessions all worked as well as I remembered USL laying down.

Now, we let things sit until wednesday when it is supposed to get back into the fifties.

Thanks for the replies and for helping me get through the tough times of waiting.

Dave

It's not just temperature-but humidity also !

A damp 55 degree place may have very high humidity !

I shoot only in 65 +and NO more then 45% humidity .
The warmer the better for finishes !

I actually warm the finish up to help it flow better !

This can be done in with putting in the sun (if you have any) orwarming on a stove or heater .

Mike

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Mike Collins