Kevin Corrigan and I were having lunch at Emma’s Grill where she makes a fine rib-eye steak sandwich. She poured us glasses of water and more coffee and Kevin said, “Thanks for the help with the layout of my painting operation. It is working just fine. Paint finishes are almost always perfect and they require almost no buffing. That Shamrock paint booth you told me about was exactly what I needed. I bought one and put it in the inside hangar slot.
“My business has really grown now that this booth is operating and my finishes are bringing me more new business than I thought I would get. I’m making good money on every plane and word is spreading. I get calls from all over the tri-state area. People have seen the finishes and want their planes painted that way. I am even taking away business from that guy in Springfield.
“But I have two complaints,” Kevin said as he took a sip of his coffee. “The first is that when I sand and prep a plane, the sanded dust gets into the paint finish when I start painting. I sweep up between paintings, but the dust is still hiding there. The second problem is that I have more business than I can service with just this one Shamrock booth.”
I could see where this was going. He needed another paint booth or a better way to do his prep, sanding, and masking at least. Our sandwiches arrived and Emma poured some more coffee. I asked Kevin if he had another hangar. Kevin was munching on his steak sandwich but stopped long enough to say, “Yes, we do have a hangar next to the paint booth and I have tried to prep, sand, and mask in there, but conditions are not right. There is very little airflow and the lighting is poor.”
“I also do a little prepping outside. The light is good, but weather is a problem around here. When it is sunny, it is too bright, then the clouds come and it rains and damages my prep job. In the winter, I just can’t do it out on the tarmac.”
“Kevin, we have to talk,” I said as I made a few notes. “How do you process these planes? Do you strip, sand, tape, spot prime, or touch-up?”
Kevin looked up and said, “I don’t like to strip in the aircraft paint booth. It messes up the floor and makes for a sloppy workplace. But we sand, tape, and touch-up in the paint booth. The visibility is very good and the accuracy of taping is very precise. It is also easy to see the progress of the sanding.”
I was thinking of ways to help him solve his problem and get more aircraft through his shop. The only thing I could think was using a separate enclosure for everything but painting. Tying up the paint booth while masking, sanding, and stripping was slowing him down and causing contamination. It was also costing a lot of energy to heat the high volume of air a paint booth requires.
I asked Emma if she had any pie and while she went for the tray, I said, “I see several areas of improvement that you could make. The first is to solve your productivity problem by adding another system. The second system could be a purpose built prep booth. The airflow would not have to be as much as with a paint booth. If the airflow is reduced to half that of a paint booth, you have adequate ventilation for doing your taping, masking, sanding, etc, and your energy costs are lower.
“The exhaust chamber should be sized to give good removal of dust and dirt while prepping and sanding. Control of dust is a big factor in keeping dust contamination out of the paint booth. Lighting should be near the same lighting levels as the paint booth.”
I picked a nice piece of blueberry pie from Emma and Kevin chose the lemon pie. We each took a bite of our pie and looked up. I could see that he was considering my proposal, but he had a few doubts.
I said, “In the automotive refinishing business, they do this stuff all the time. They have a special booth designed for this lighter duty operation that allows for higher productivity. Your production would be less than a day in the sand/prep booth and another day in the paint/markings booth. But where it took you two days before in a single booth, now you double your productivity and do a plane a day.”
A look at crossdraft and downdraft paint booths By Rich Thelen From top: Crossdraft with forced draft plenum doors. Downdraft showing filter house. Fighter booth. It goes...