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Cold Shop Tips?

Mark Durrenberger

Mark Durrenberger

Joined
Jun 4, 2021
Messages
23
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311
Location
Hudson, MA
Website
www.instagram.com
I recently moved. My new shop is in an unheated basement. Lately it's been running about 50 - 53 degrees F (10-12C).
The dust makers (lathe, bandsaw) are in a nice, well insulated space and can be brought up to temp quickly with a 1,200 watt heater. But the area where I want to do finishing (not dusty) can't be enclosed. So it's cold all the time. I've discovered that finishing a piece at ~50 degrees is suboptimal. Any recommendations?

I was thinking about building an insulated box with a thermostat controlled heater (not unlike a wood drying cabinet). And keeping the box at about 70F (21C). Will that work? Is a lower temp OK (65?) My preferred finish is wipe on polyurethane. Also, should I keep the finishes in "warm" storage?


Thanks
 
I think a portable propane heater, or even a kerosene heater would work. However I would get the room heated and switch off the heater before applying finish.
 
Hello @Mark Durrenberger. Yes, I have an idea, but it is a full-on, no-holds-barred, damn the torpedoes, money is no object proposition.

Insulation of the entire foundation and the floor joist/rim joist area above the foundation, and modification to the building HVAC system to provide a source of conditioned air into your workshop.

I'd talk to your municipal building inspector to discuss your local energy and building code requirements to cover all your bases. And electrical requirements while you're at it.

And as a side note, machine-specific dust collection is going to be a very serious matter to make sure your HVAC system isn't sucking in your wood dust, contaminating the hot and cold heat exchange surfaces, contaminating open burner systems, and making a mess of ductwork. Covering the return air duct openings from your basement area with their own pleated furnace filters (MERV 10-11 rated filters might do the trick, and they will be oversized for the duct opening) will go far to keep wood dust out of ducts/furnace/air conditioner. Replace the filters monthly.

Sorry, Wyatt, in my state (MN), "Unvented room heaters and unvented decorative appliances shall not be installed in any dwelling or occupancy." (This is a MN code amendment to the International Fuel Gas Code.) It may be legal under certain circumstances in other states, but dead is dead, and it's a bad idea everywhere, legal or not.

Be comfortable, be safe, and enjoy your craft!
 
I used an old fridge with a 25W light bulb to keep my finishes warm when we lived up north. I like your idea of a thermostat controlled heat source and it may be your most affordable option.
 
Mark Durrenberger said:
I was thinking about building an insulated box with a thermostat controlled heater (not unlike a wood drying cabinet). And keeping the box at about 70F (21C). Will that work? Is a lower temp OK (65?) My preferred finish is wipe on polyurethane. Also, should I keep the finishes in "warm" storage?
Click to expand...

I think that would work, as long as there was enough ventilation to let the finishes dry/cure.
There are plenty of temperature controllers on Amazon, for example. I bought two, one for a small fridge to temporarily store peafowl/guinea/chicken eggs at the optimum temperature for hatching. Another to control the temperature of a brooder heater for little chicks. Easy to use - put the temperature probe in the enclosure, set the temperature, plug in the fridge or heater.

JKJ
 
I keep one of those oil filled heaters that look like a radiator on all the time. It heats surprisingly well and I don't worry about open flames.
 
The hvac for the floors above are heat pumps. The water heater is gas. But that’s not subject to dust from my tools since they are in an enclosed space. Yes the basement walls need insulation. But the rim joists are done and the floor above is mostly done (1” of spray foam installed for air sealing and 6” of fiberglass batts coming soon, almost half of the basement concrete wall is above grade so the walls are cold. )
 
Two to four inches of rigid foam insulation on the walls with good air sealing and filling the rim joist cavities with spray foam will make a world of difference. We also have foam under the concrete slab, but it's probably too late for that in the new place! The zoned heat in our basement has never, to my knowledge, turned on with the thermostat set at 64 degrees despite some exposed wall (not as much as you have). No good reason for a basement to get that cold.

My shop is 64-65 during the day in winter, dropping to mid 50's overnight and I haven't had any issues with oil based poly drying. It takes a little longer than when it's warmer but still gets there. Some of the WB finishes call for higher temperatures so I crank the thermostat up a couple degrees when finishing a larger project and keep the heat on overnight. When I needed to speed up a tung oil finish on some small pieces I made a drying box by putting a light bulb in a big cooler with a temperature controller; that let me keep them at 85 for several days. A violin building friend used a big freezer in a similar fashion for curing the varnish on her instruments; they needed an elevated temperature for a week or two between coats because of the kind of varnish she used. An insulated purpose built box would also work fine.
 
Insulation!

Strap the walls, fit foamboard or rockwool between, cover with drywall, osb or similar, paint and enjoy. The thicker the better. Do the same on the floors if you can (not drywall- Adventech or exterior grade plywood)

Unvented heater in a basement is a terrible idea, adds CO and H20 in a poorly ventilated space. For that matter, using solvent based finishes without adequate venting will catch up to you as well.
 
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It looks like I didn't fully understand your question. I thought you were talking about a drafty outbuilding. In the case of your concrete basement, ideally good insulation and proper central heating system is your solution.
 
Portable electric space heaters are an easy and inexpensive solution. Another solution is to use a finish that will cure at the temperature of your shop in winter.
 
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