Work areas for spray painters...

James_in_MD

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for those of you that choose spray not roll, how/where do you set up work areas? Do you hang drop cloths too or just lay them on the floor? How much collateral damage can the spray cause? I'm considering spraying in a somewhat empty single bay 2 car garage, but I will have all kinds of crap along the walls of the garage. It will not be practical to cover everything, so I imagine I would need to hang tarps to create a wall around the cab I was painting. I do have a respirator. Does this sound reasonable? I do not want to paint outside due to bugs, etc.

Also, can a small compressor be used for this kind of job? My compressor is around a 4 Gal capacity.
 
It might be easier and more comfortable to wheel it out onto the driveway, that way you wont risk painting your knick knacks and the fumes & vapor will dissipate safely.
 
I paint most of my games outside as I have no room in my garage. I just can't paint in bad weather, including breezy days. When I did have space in the garage I set up something like you describe. Basically made a makeshift paint booth. You definitely need the respirator and good lighting. The spray will fill the booth pretty good. I still have a section on the ceiling of my garage that has a paint mark in the shape of the booth I made. Keep your compressor out of the booth and the garage door open so you can exit the booth to a well ventilated area easily. Make sure the area in the booth is big enough to easily move around all sides of the cab. Personally I used a clear plastic material rather than a common blue tarp. This allowed me to place my lighting outside the booth area.
 
I made a temporary paint booth in the back patio of our house.
Like Dan stated you need a respirator and good lighting.
I also used clear visqueen for the walls of the booth.
If you spray with an HVLP then the 4 gallon compressor will not be nearly big enough.
Spray guns use a lot of cfm.
You need at least a 20 gallon min. tank.
I used a 33 gallon tank and it worked pretty good.
 
If you paint in your driveway make sure your vehicle is upwind ...I ended up with some blue specks on my front bumper one time..luckily I noticed it and removed it with a little water...:rolleyes:
 
[FONT=Verdana,Arial,Helvetica,sans-serif]Here's a good explanation of CFM and atomization. You can't go by tank size, you need to know the cfm of the gun, and compressor.

An HVLP gun requires more VOLUME of air to operate (the V in HVLP, High Volume Low Pressure). Now you may notice that your HVLP gun is adjusted at maybe the same PSI as an old conventional gun, around 50 lbs at the gun (many HVLP guns are set at much lower though) so where is the "Low" in PSI they are talking about? It is at the actual air cap where the air and paint come out. An HVLP gun has only 10 lbs at the cap while a conventional has upwards of 50! So the VOLUME of air (CFM -- Cubic Feet per Minute) is the key to proper atomization with an HVLP.

If you have a gun that requires 15 CFM you will need a compressor and plumbing that will produce that at a very minimum. There are HVLP guns that need as little as 7.5 CFM so you can get good results even from a smaller compressor. Air supply is a complete subject by itself, so let's assume that you have the air supply needed and move on to gun setup.

So atomization is the key, but why? Why can't you just lay it out wet and let it "flow", as an old painter will say. Picture a jar full of bb's; they will represent small, atomized droplets of PSPC. The gaps in between the bb's is solvent. Now picture a jar filled with marbles, they will represent large, poorly atomized droplets of PSPC. The gaps in between are, you guessed it, solvent.

If you apply your PSPC in large poorly atomized droplets, what you will have is a film full of solvent. This can and will cause slow curing, shrinkage and dieback (the loss of gloss in the hours and days after application).

So, now that we have learned the need for gun setup, how do we do it? Let's start with the fluid tip choice. The newer high-solids low-VOC PSPC products need to be broken up more, so a smaller fluid tip is needed.

Basically you want the smallest fluid tip that will still allow you to PSPC the particular part you are PSPC'ing, keeping the entire thing wet and in a fair amount of time. In other words, a 1.0 tip would be beautiful for clearing one fender, but would be lousy to paint a complete. The application would be way too slow, and the first panel would be way too flashed by the time you got back around to it. So you need to compromise -- a 1.3 is a great all-around tip, while a 1.5, though getting a little big, can get you by. If you read the tech sheet on the particular product you are shooting, it will have a recommendation for fluid tip size.

There are needs for other tips. For instance, when shooting polyester primer you may need as big as a 2.3, but for urethanes and epoxies, the 1.3 or 1.4 will work great.

As an example of the use of a 1.3 tip, I did a test once that proved the point well. I shot two panels of metal with a medium solids urethane primer. One was shot with a 1.3 super high atomizing top of the line topcoat gun. The other was shot with a 1.5 (or a 1.7 I can't remember) "hoser" primer gun. Three coats were applied and after a full cure (the one shot with the larger gun took MUCH longer to flash and cure by the way) the film thickness was measured. The one shot with the 1.3 tip was 2 tenths of a mil thicker! The larger gun laid out the marble sized droplets full of solvent, and when the solvent flashed the film shrank.
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