Minimum Temp for Spaying Nitro Lacquer

[Mark Crenshaw]

Question: What is the minimum temp for spraying nitro lacquer?

I have my temp spray both set up in a very large shop, vetilation taken care of. But todays weather is causing me concern. I have had the heaters fired up for an hour or so and the temp in the shop is 55F with humidity of 45%, outdoor temp is 35F according to my digital weather station. I have all the pieces acclimated to the room, retarder on hand.

Will I be OK spraying today. I thought I had read threads of folks spraying down to 40F or so...maybe I'm confusing my facts.

Any help very much appreciated. I really want to get these guitars sprayed today...last day of the year and all. It's a goal to get them done this year but not if it means making a mess of them.


Peace,
Mark

[Howard Acheson]

NC lacquer is an evaporative finish. Basically, temperature has no affect on evaporation. You can spray at almost any reasonable temperature. I've sprayed NC lacquer at below freezing with no real change is drying speed.

[Tony Bilello]

I generally dont like to spray at less than 55*. I'm not sure of the recommended min. temps. I cant sem to find a Product Data Sheet (PDS) on line. I am out of town and all my PDS and MSDS sheets are in my shop.
Anyway, the real problem with lacquer is humidity. Anything above about 85% is prone to blushing. It looks like a fog on the surface of the finish. It can be reduced or eliminated with the addition of 'retarder'. Above 90% humidity, blush is almost guaranteed and most people would never spray at that humidity level.

[Phil Phelps]

Spray away. What really affects the lacquer is humidity. It causes blushing which can be delt with using a retarder. I don't think it'll bother you today.

[David Christopher]

Mark, I use nitro lacquer most of the time and like others said humidity is the enemy but at 45% that will be great....I have sprayed at 85% and had good luck

[Mark Crenshaw]

Thanks for all the info.

I sprayed the first coats and it went fine. I'm using Behlen pre-thinned instrument lacquer and I added 2 capfuls of retarder to my large cup and it laid down very nicely and flowed out smoothly. I got 2 bodies and 2 necks sprayed today. I'm going back this evening to put another coat on aveything. I'm not even going to bother with trying to cycle the heaters as long as the shop stays around 50F.

Thanks again,
Mark

[Tony Bilello]

Great going Mark.
Even though retarder is not necessary at lower humidity levels, I always add it to the whole batch when I open the can. Although not needed at times, it helps the flow characteristics. I also add several drops of fisheye eliminator to the batch. This is normally not needed on new wood, but I also do refinishing.
Also notice that the lacquer will get thicker with the lower temps. Dont be afraid to add a little thinner. A little goes a very long way. I use anything I got handy for a quick test piece to see how fan looks and to check flow. It could be anything from a piece of plywood to a piece of cardboard. One pass will show you what you got.
I assume you are using a cup gun or gravity feed cup, so if you add to much thinner and the mix is too thin, just dump the whole cup into the 1 gal can with the other lacquer. It will mix in and the batch will be ever so slightly thinner and then just pour another cup of lacquer from the can and try again. Lacquer is wonderful stuff.

[Tony Bilello]

....... I really want to get these guitars sprayed today...last day of the year and all. It's a goal to get them done this year but not if it means making a mess of them.
Peace,
Mark

Mark

In cooler weather, you can put on a coat about every 30 minutes. When shop gets up to about 65*, you can recoat about every 15 to 20 minutes. At 70* and above, I recoat every 10 minutes.
Three coats is usually sufficient.
As you get used to lacquer, which is very quickly, you will find yourself handling and moving things around after only about 5 to 10 minutes.

[Phil Phelps]

Question: What is the minimum temp for spraying nitro lacquer?

Any help very much appreciated. I really want to get these guitars sprayed today...last day of the year and all. It's a goal to get them done this year but not if it means making a mess of them.
Peace,
Mark

Mark, I missed the "guitar" part. I doubt, very seriously, that a couple of coats will do the trick. It's not unusual to put 20, 30, maybe 40 coats of lacquer to get a great finish on a guitar. The Strat is about 30 or so. I did it last year. Many hours of wet sanding.

[Harvey Pascoe]

Mark

In cooler weather, you can put on a coat about every 30 minutes. When shop gets up to about 65*, you can recoat about every 15 to 20 minutes. At 70* and above, I recoat every 10 minutes.
Three coats is usually sufficient.
As you get used to lacquer, which is very quickly, you will find yourself handling and moving things around after only about 5 to 10 minutes.

I'll lay out 10 or 15 parts on my spray bench and go right down the line one after the other so that each gets three or four HEAVY coats every 5 minutes (touch dry at my temps), then I give it a rest for the day, and repeat the next day after sanding until I got 16 coats. More than that it takes to long to cure for sanding between coats. Don't want gummed up sand paper, ya know!

Before going for the 4th coat, I wait an hour or so and then test with my finger nail to see how soft it is. If very soft, I won't do the 4th since that extends the cure time for sanding to more than overnight.

My working temp range is 60-90 and humidity is always high. Most of my blushing disappears after a day or two. If humidity over 80 and temp under 60, I hold off.

[Mark Crenshaw]

Hi folks. Thanks for all the replies. I appreciate the good info. I have a gallon of Target EM6000 on the way and I'm wondering if I need special equipment to spray it. I have an HVLP production gun with 1.4 and 1.8 tips. My touch up gun, also HVLP has a 1,0 tip. My compressor keeps up fine with either gun shooting nitro lacquer.

Also, I tried to find the info on their site, but couldn't...are there any explosion concerns with the EM6000?

Peace,
Mark

[Jim Becker]

No...zero...explosion concerns with the EM6000. You'll see on the label that it has a zero for flamability. Use a respirator to keep particulates out of your lungs, but there is almost no odor, too. I run my air cleaner to just clear out the particulates.

As to the gun, "out of the can" the Target Products spray well with my #2 projector set on my Wagner gun. I don't recall the size, but it's the same one I'd use for NC lacquer if I ever chose to use it. (which will not happen)

Note that EM6000, despite the name is not a "lacquer", but Jeff Weis formulated it (and it's predicessors) to have lacquer-like properties. Like all water borne products, it's an acrylic. I think you'll really like it. Do be careful with your coating thickness. Go moderately and use as many coats as you need to build your finish, just as you would with lacquer. If you use any oil, etc., to pop your grain, be sure to use a thin barrier coat of de-waxed shellac or Targets water borne shellac product (I prefer the real stuff myself) as a barrier layer. I also like to seal with shellac after water soluble dyes. It cover both the sealing and makes grain-raise/nib removal quick and easy with 400 grit abrasive...a few quick swipes and then clean it off thoroughly.

[Mark Crenshaw]

No...zero...explosion concerns with the EM6000. You'll see on the label that it has a zero for flamability. Use a respirator to keep particulates out of your lungs, but there is almost no odor, too. I run my air cleaner to just clear out the particulates.

As to the gun, "out of the can" the Target Products spray well with my #2 projector set on my Wagner gun. I don't recall the size, but it's the same one I'd use for NC lacquer if I ever chose to use it. (which will not happen)

Note that EM6000, despite the name is not a "lacquer", but Jeff Weis formulated it (and it's predicessors) to have lacquer-like properties. Like all water borne products, it's an acrylic. I think you'll really like it. Do be careful with your coating thickness. Go moderately and use as many coats as you need to build your finish, just as you would with lacquer. If you use any oil, etc., to pop your grain, be sure to use a thin barrier coat of de-waxed shellac or Targets water borne shellac product (I prefer the real stuff myself) as a barrier layer. I also like to seal with shellac after water soluble dyes. It cover both the sealing and makes grain-raise/nib removal quick and easy with 400 grit abrasive...a few quick swipes and then clean it off thoroughly.

Thanks Jim! This is great info. With regard to the sealer coat, my guitars already have a couple of coats of nitro on them...one was dyed direct on the wood, then sealed with nitro, the other was sprayed with nitro shader coats to get the color and then with an overall nitro clear coat. Is this enough of a barrier or do I still need to use something else? I had read that water based acrylics would spray over and burn into nitro without issue...is this correct?

Peace,
Mark

[Larry Fox]

Agree with everything Jim said about EM6000. However, since this thread started out as one discussing min temp, you can't spray the EM6000 in cooler temps like you can shellac or NC. Definitely pay attention to the recomendations on the can.

[Mark Crenshaw]

Agree with everything Jim said about EM6000. However, since this thread started out as one discussing min temp, you can't spray the EM6000 in cooler temps like you can shellac or NC. Definitely pay attention to the recomendations on the can.

Also great info. Thanks Larry!

Peace,
Mark