Air temp to paint gun?

[svr]

Its getting cold now, in the 20's at night. I can heat my shop enough to get paint booth and body panels in the mid 60's to 70 or so without much trouble. Problem is my compressor is in another building that is unheated. Very likely that air temp in that building will be in the 20-30 degree range. I know the compressor will heat the air some but it runs 50-60 feet to my shop and will probably cool a fair amount. Question what will happen spraying 2k urethane bccc on 65 degree panels and ambient air temp with cold air? Booth will have 65 degree air moving through it but will cold spray gun air cool things off to much? Any suggestions or thoughts appreciated. May have to do a test panel or 2. Thank you

[Foot Stomper]

Air temp won't make any difference, so long as your product in the pot and metal temp is 70.

65 is a bigger issue. Room temp and metal temp need to be higher because 2K urethane need heat to cure. They don't dry, they cure. If metal temp is too low, they cool the urethane down to stall. When stalled from curing, they die and will dry, but not cure...even if warmed up later.

Metal temp is always cooler than room temp, and it's the most important one to measure. 65 can become 60 or less very easily so be very careful at 65 because you're at the low end of acceptable range. The TDS will surely tell you what the temp range is. Maybe the product you've chosen has a lower temp range?

I like your idea of test panels. Watch for solvent pop and thumb printing. The reducers are going to be slow to flash and the urethane may not completely cure.

[svr]

Thanks, data sheet says 60 is minimum, been experimenting with different ways to heat the booth, i can get the air in the upper end of the booth into the mid 70's and the upper end metal about 70 without much trouble, the metal temp on the far side near the floor is in the low 60's. May have to put a fan in the booth to help even out the temps before i shoot it, turn it off while i shoot and then turn it back on after the fumes exit. Also working on a way to heat the incoming air in the booth which may solve the problem.

[Foot Stomper]

Sounds like you have it figured out.

For the sake of anyone reading this post, please always use proper PPE and take all safety precautions when working with these chemicals.

[Macdaddy1]

Foot stomper

Just wanted to say that your insight and advice is most valuable and has helped me on several levels with my project, equipment and set up. So a real big thanks for all of your contributions.

Pat

[Foot Stomper]

Originally Posted by Macdaddy1

Foot stomper

Just wanted to say that your insight and advice is most valuable and has helped me on several levels with my project, equipment and set up. So a real big thanks for all of your contributions.

Pat

Thanks Pat. There's a few fellow members on here that know a lot more than me, so there's a deep pool of knowledge and help on this site for sure!

[svr]

Did some test panels this morning and had something interesting happen. I have an old trailer fender i was using as a test panel, i wanted to split it down the middle and do 1 half 1 color of my combo and do the other half the other. I taped it yesterday afternoon with green frog tape to mask the 1 side off. After I shot the base coat I waited about 30 min and started to pull the tape. It looked like the solvent from the urethane paint had melted through the green frog tape and left the sticky from the tape on the fender. I was in a panic until i found i could rub the glue it left with my finger and roll it up into a ball. I waited the required hour for the color to be tape safe and used 3M blue tape on the fresh paint to do the other side and shot the other color. I pulled that tape as soon as I had given the gun a quick cleaning and all was good, no glue residue at all and no pulled paint from the first color. Not really sure what happened but will stick with 3M blue tape going forward unless somebody can explain what happened. Shot some clear coat on top of it all and so far all is good.

[Foot Stomper]

The urethane solvents likely attacked the frog tape as it's not made for automotive. The 3M is made for automotive paints.

[Indian113]

Here is a Tip from a Buddy of mine that painted Motorcycle tanks and Fenders. In the winter he wrapped them in old electric blankets. Then they were warm all the way through. I am going to paint my truck in pieces so I might do the same thing. I am going to try and save on the Gas Bill this winter.