HLVP Spraying in the winter

[Andrew Seemann]

Hi,

For you fellow folks in the frozen north, how do you do your HLVP spraying in the winter?

I'm using water base, so no need to worry about flammability, and I have the materials to do the insulation board/box fan spray booth set up. I want to exhaust outside, as I don't want the VOCs or overspray in the shop. I'm wondering how to do a setup that exhausts outside, with the outside temp being likely somewhere between 0F - 20F. If it is much colder than that, I probably would wait to finish.

I could just open the swinging barn doors and put the insulation board, fan, and filters between them and open a window for makeup air, but I think I would cool the shop down pretty quickly, even with the unit heater and stove going. The shop is about 670 sq ft in size with 9 1/2' ceilings. I would likely be doing only one or two furniture items at a time, no mass production things, at least none planned

Any ideas?

[Jim Becker]

Both the finish and the environment that the finishing will be done in must be within the temperature range that the finish manufacturer specifies...that's typically north of 65º or so at the lowest point. I only use waterborne finishes; my shop has heat and I do not exhaust outside. I wear a proper respirator and eye protection and run my air cleaner to grab suspended particulate from the air. I spray in a particular area of the shop and stop all other work for the duration of the finishing process. Ideal? No...having a formal spray booth with exhaust and a proper air exchanger would be the best. But that's not possible in his particular shop.

[John TenEyck]

I put up a temporary spray booth in my heated basement shop, with exhaust out a nearby window and make up air from another across the shop. There is so much mass in my shop between the concrete walls/flor and contents of my shop that the temperature hardly changes even when I spray for an hour straight. As Jim said, you need to maintain the minimum application and curing temperature when using WB finishes. Beyond that, keeping dust and overspray from falling on the fresh sprayed work are about the only must haves.

John

[Patrick Kane]

I spray in an unheated garage that is tucked into the hillside. Typical winter temps are usually in the low 40s. This will almost guarantee an orange peel finish when spraying waterbourne finishes like GF endurovar. What i do to a certain level of success is keep the workpiece in my conditioned shop up until the last possible second im going to spray. I then wheel in a portable electric radiator heater that blows warm air onto the workpiece. Finally, i warm the finish in the fuji cup with a heat gun. I dont want it blazing hot, but i go until i have the quart of finish to about 70°, since my shop is usually 55ish during the winter. Finally, i tuck the actual HVLP turbine behind the mandoor into my shop, so its sucking in 55° air to my gun and not 40° from the garage. With the heater on the workpiece and warm finish, i rarely have curing issues through the winter. Not as ideal to spray with the garage door shut and run the risk of the finish not leveling as nicely, but its what i have. I routinely used to finish with oil-based varnishes years ago without supplemental heat and those were fine at or below 40. Takes forever to cure, but they leveled fine and cured.