Backyard paint booth
I've painted at least 10 cars in either the driveway or my garage, and here's what i have learned.
The prep work is very important. If you can see a lump or dent in primer you damn well are going to see it in paint.
clean, clean, clean... start by blowing everything in the garage off with the air gun - shelves benches rafters, wherever you see dirt or dust. let it settle, then vacuum everywhere you can with a shop vac. don't sweep, it will stir the dust back up.
Get a roll of large plastic sheeting that they use under concrete slabs and hang it on your garage walls from floor to ceiling. this will keep the dirt out and let you hose the spray area. Allow overlap where you stop or have doors. Keep the plastic where the overhead door is so you can roll it up and secure it with a bungee or some wire to get the car in & out. Now hose down the whole thing and sweep the excess water out the door. that should take care of the spray booth.
You will need to move air through the spray booth. the paint overspray will fall out of the air into your paint and be just like dust. I use a box fan on one side to suck the fumes out, and rig a large AC filter on the opposite end to let clean air in.
The next most important thing is to have a good water separator. Water in the air line will ruin a paint job in a heartbeat. Drain the compressor tank as well.
Air pressure will vary with the type of gun you're using and the paint you are applying. if you have an old hood or body panel, practice laying down some smooth strokes that overlap about 3". I usually spray a medium wet coat first, then wait about 15 min. and spray a full wet coat next. Metallic is much harder to lay down and get the color even.
Blow the car off with the airgun outside the booth before you are going to paint. make sure you get all the nooks & crannys. Use a tack rag to wipe the car down before you spray. Hose and sweep the water out of the booth again right before you roll the car in to spray.
Now say a prayer and make a burnt offering cause you're gonna need all the help you can get.
Good Luck! :thumblef: