Shop Heat and Finishing Quality

There are important reasons to keep your spraying area warm in winter. April 27, 2007

We're building a new finishing room. Our shop is in the Northwest with average winter temps of 40-50 deg F. I am trying to decide on a heated air makeup unit or to just blow in outside air and put IR heaters on the wood. IR would be a lot cheaper on the gas bill, but would it do the job? We make chairs and finish with Becker Acroma pre-cat lacquer.

Forum Responses
(Finishing Forum)
From contributor L:
I don't think an IR unit would comply with OSHA standards in a spray area. The surface of the element is too hot and is a possible ignition source for the lacquer. If you are using WB, it should be fine. You will have to determine the optimal distance between the heater and the objects curing. If you cure it too fast you may get solvent pop. The distance will change as the temp changes in the room; could be tricky.

From contributor J:
BST, board surface temperature, is just as important to maintain as oven temperature for stain drying or varnish curing. You really need to keep the minimum temp in the finish department no lower than 65 F. All viscosities are based at ambient temps, which is 77 F. The colder the paint, the thicker the material. Even your parts finished need to be at least 65 F. Colder parts retard dry, cause bleed back of stain, blisters and orange peel. What you're trying to obtain is consistency in your paint temp, BST, and ambient temp. Any one of these being way off will cause you problems.

From contributor I:
I.R. can be tricky, especially going from cold substrate and cold coating to that kind of intensity. Natural gas heat is 1/3 the cost of electricity. You could buy a boiler and make a convection tunnel. This is the most economical way to go, and the most idiot-proof.