Can I Spray Ext. Latex ?

[LampLighter]

I am making some shutters. I oil primed them tonite. I want to use exterior latex paint. Can I put latex paint into an automobile sprayer, and spray it ? Will it come out of the nozzle ? What air pressure to set my regulator at ?
Probably use a cheap Harbor Freight gun, not a good Devilbus or Binks.

[Bill Gunn]

I've done it with an airless, but I'd be suprised if it went well with an air sprayer. I found this on the net...

Latex paint is viscous and very opaque so an ordinary spray gun found at your local hardware store will not work well. To spray latex please look at a gun with a larger orifice size. 1.5-1.6 for pressure feed. 2.0-2.5 for gravity feed. Siphon feed not recommended. The WB is a terrific choice for spraying latex paint. Also look at the finishline III latex gun.

[Sidekick]

I've done it. I used my old Devilbiss (I ain't got no cheap paintgun) siphon feed. I thinned it with water and used the same for cleanup. Use about 40 psi or so for spraying. You'll have to play with it a little bit until you get the viscosity right but it works fine. Hot soapy water works good for cleanup. Don't try paint thinner with latex, you won't be happy. Heck you might even be able to clean the thing in the dishwasher but you'd probably better ask first. Read the can. If it says to thin with water then thats what you need to use to clean it too.
One other thought. Air compressor. If it's a small job like shutters a small 20 gallon garage compressor will probably work but you'll have to wait on it. There's no such thing as too much air. I have 20 cfm of free air at the valve in my shop and sometimes it's not enough.

[Bayrat]

Yes you can.

I've done it many times with an old Binks 27 when we had to paint complex shapes for museum displays. Even had to do 100 full sized mannequins once for a display on antique clothing !

The newer HVLP guns meant for heavy bodied auto paints and primers are even better for latex than the old non-HVLP's.

You don't need much water - about 10 % should put you in the range. May need a bit more if it's very hot and dry where the spraying is being done and the paint is drying before it flows out (leaves pin head sized lumps). Use less if it's damp and cool. But which ever, don't put anymore water in it than is needed, it can quickly get runny.

Test the air pressure for the type gun your using to get best atomization of the paint.

And you may have to use one more coat than recommended to get the same film thickness coverage.

Another thing about it. Adding water and spraying it on usually makes latex the next level of shine. Flat becomes low gloss, and low gloss becomes gloss, etc.

And never put a spray gun in a dish washer if you want to use it again. Automatic dish detergent is extreamly harsh, some have lye in them and it will do a job on any aluminum, the valves and seals.

Bayrat

[Sidekick]

My dishwasher remark was meant to be tongue in cheek. I don't recomend that you do that. I did actually put a carburetor from a 1950 John Deere in mine once. It seemed like a good idea at the time.:eek: I painted aircraft for 5 years during my bluesuiter days and you are right an HVLP gun can be a sweet tool if you understand how to adjust the gun and the material for optimum results. I'd probably look at a gravity feed instead of siphon but if all you are ever going to do with it is small odd jobs every 5 years it probably doesn't matter. Buy something cheap. Speaking of painting, I just finished wet sanding a motorcycle helmet. Probably try to shoot it tomorrow.

[Bayrat]

Sidekick,

I figured that, ;) ...... but ya never know who doesn't have the level of experiance to understand that. It's one thing to trash a $25.00 Harbor Freight Tiawan knock-off, but I'd hate to hear of someone trashing a good Binks, Devilbiss, or Sharp. :(

But ....... maybe I should fix my dishwasher ....... at the rate solvent prices are going up, that may be the only choice left to us !! I just paid over $68.00 for a 5 gallon drum of cheap wash lacquer thinner.:eek: It was $34.00 only last December.

My painting has been in marine repair, then 9 years as a museum exhibits tech, and the last 26 years in restoring classic era cars for private collectors.

Bayrat.

[Sidekick]

Restoring classic cars eh? That's pretty cool. I don't do anything like that but I have put a new shine on a "few" antique tractors. I've been fortunate to do a lot of work for family members. It's something I really enjoy. Here's a pic of my Great Uncles '51 G John Deere. It was already very very straight to begin with so it was a pretty straight forward job. That old man took better care of his equipment than he did himself.:confused: Speaking of ruining a good paintgun, in my Air Force days someone who was never identified tried to "clean" a Binks Mach 1 in our cabinet bead blaster. It looked like it had been shot with a shotgun and then drug down a gravel road. Pretty dumb. I pretty well knew who did it but they wouldn't admit it. Check out that shine!