Winter finishing

[Tom Porter]

This may not be the best forum for this but it seems like both a workshop question and a finishing question. What do other do about finishing in the winter? I live in the mid-Atlantic, where it is currently mid-30s and will be for the foreseeable future. I have a few projects I'm finishing for the holidays that encompass a variety of finishes (spray paint, spray poly, brush on poly, etc). My shop is in a full unfinished basement, which has two small windows, a outside door and the gas furnace. I also have an attached garage. When the temperature is above 50, I try to do any volatile finishes either in the garage with the door open or possibly in the basement shop with a small fan in a window to move air. The problem is, at this time of year, its too cold in the garage (insulated but not heated) as it's usually below 50, which is usually at the bottom of the range on the instructions for most finishes. If I use the basement, keeping the windows and door open will be like trying to heat the outside to some degree but not opening them means poor ventilation and fumes getting into the house. Case in point, I used a contact cement in the basement a few years ago and thought I'd give my wife and myself brain damage from the odor.

Eventually, I'm going to do some degree of renovation to the shop and I may be able to isolate the furnace from the work area and add some degree of ventilation. I currently do not have a dedicated dust collection and air cleaning system but those are on the agenda, too. Any suggestions of how others deal with related issues?

[Zachary Hoyt]

I can't speak to your particular situation, as I only use Tru Oil anymore. We live in a converted barn and the old house next to it is only used for visitors during the warmer months, and I drain the pipes for the winter. There's a wood stove in there, so when the temperature goes below 50 or so I save up my finishing till I have enough instruments ready to make it worthwhile and then I take a day when I have time, usually a Sunday, and light a fire in the stove at 7 or 8 in the morning. By 11 it's warm enough in there to get going and I do 5 coats during the remainder of the day and evening, 2-3 hours apart. Then overnight I let the stove go out, and in the morning I go over and bring everything back to the heated shop. In the summertime I just do the finishing in an outbuilding, which is not heated and has some ventilation, and that seems to work fine too, though I have to space the coats out more. Solvents and chemicals in an unventilated living space can be quite unhealthy, so I wouldn't take chances with that.
Zach

[John TenEyck]

I work in a basement shop, just like you, but I have heat and keep it at 65F in the cold months. I use wipe on varnish; the fumes aren't much of an issue. I apply shellac and water based finishes by hand, too. Again, the fumes are minimal, at least to me. But I also spray a lot of shellac and water based finishes in a temporary spray booth that is vented with my 1200 cfm DC fan out a nearby window. Make-up air comes in through another window. I can spray for an hour w/o much effect on the temperature in my shop. The furnace comes on occasionally, but not like what you would think and I used to keep it completely off while I gained confidence that the DC wasn't pulling it's make-up down the chimney and the temp. only went down a couple of degrees. There's just so much mass in the walls and floor that it buffers the effect of the cold make-up air. I found that the open window provides all the make-up air the DC fan needs, so now I leave the furnace on and have had no issues for the 5+ years I've been doing this. I'm not advocating others copy what I do, only that I've found it safe for my purposes. Also note, I spray no solvent based finishes besides shellac, and I only did that after calculations with regards to my particular system convinced me it was safe to do.

John

[Mike Newell]

Hello,

I'm in Wisconsin. I have a heated basement shop. When i finish a project or use ca glue for pens, etc i use a 8” HF blower. I cut a piece of 1/2” ply to fit the window and attached a 8” metal piece of duct to the center of the ply to hold the blower hose. Then i attach the blower hose to the blower and metal duct and vent everything outside. Hope this makes sense and helps.

Mike

[Lee Schierer]

I live in northwester PA and have faced the same problem over the years. I have used Deft Clear wood finish for many 30+ years on my projects. I have successfully applied it at freezing temperatures (below 32 F) in an unheated garage with no issues. It cures slowly but it does cure over night. I apply it to one horizontal surface at a time, letting it set up before rotating the part. I also let the project cure at least 4-5 days after the last coat so that the finish has more time to set up. I rushed it once and the pores in the wood where the finish wasn't fully cured developed dozens of small bubbles on the surface.

This past spring I wanted to use MinWax polyurethane on some trim in our family room/office that I was remodeling. It was in late February and early March. I tried a sample piece by wiping on the poly and laying the piece horizontal in an unheated space. Once again curing seemed to take 24 hours, but the finish did cure. This was the regular fast drying poly.

Try a test in your unheated garage and see how it turns out.

[Doug Hepler]

Tom,

Brainstorming (random thoughts)

I don't know your details but perhaps you could apply finish in your garage, let it tack up overnight and then bring it into the house to finish curing.

You said that your garage is insulated but not heated. Is the door insulated? If not, you can add insulation to an overhead garage door fairly cheaply. That will help. My garage stays above 50 when the weather outside is in the 20's overnight. I can get it to 60 with the heat from incandescent lights. Also, consider running a small space heater to get the temp up to your minimum (60 deg?) Since it is connected to the house you can leave the connecting door open for a while before you apply finish to warm it.

Consider water based varnish like acrylic. It does not smell too bad compared to shellac and varnish and it dries fast.

If you are finishing smaller objects get/make a finishing box out of 1/4" ply, cardboard, etc and warm it with an incandescent light bulb.

Doug

[Wayne Lomman]

Monitor humidity, dew point and substrate temperature as well. You can get away with a lot if the substrate is warm even if the air is cold. Only work when the substrate temperature is more than 3C above the dew point to avoid unplanned milkiness or loss of gloss. Cheers