[4]

Preparing a shop for sub-zero temperatures

[3]
[10] Like what you see?
Click here to donate to this forum and upgrade your account!

ThinWoodsman

Newbie
Registered
Joined
Jul 8, 2018
Messages
10
Likes
2
#1
I know the how-do-I-heat-my-shop-in-winter topic has been done to death, so I'll try to keep this pretty limited in scope.

Recently, I reached the limitations of the shop in my basement with its benchtop equipment. There is a barn on my property with a concrete pad the size of a single car bay. To make a long story short, I built a shop on that pad, and acquired some full-sized machines (14" lathe, knee mill). The walls and ceiling of the shop are insulated (~R21 on the walls, ~R30 on the ceiliing), but the concrete pad is not. The shop is 12x28 ft, so 336 sq ft.

Winters here (NH) get cold, 2018 being a great example - about three months solid where it didn't get above freezing, with lows somewhere around -10, -15 degrees for a week or two at a time.

Ideally, I would heat the shop 24/7 to 35-40 deg (F), but that seems impractical for reasons others have mentioned. So I'm looking at some sort of as-needed heat: a kerosene/propane heater with the door (into the rest of the unheated, uninsulated barn) open, or an electric heater.

What I would like to know is: what are the drawbacks to leaving the shop unheated in such conditions? Specifically, do oils and solvents and the like need to be removed from the shop during winter? Do sensitive measuring instruments (dial indicators, micrometers, gage blocks/pins, etc) suffer from being stored so far from their operating range? Will repeatedly heating the room from well-below-freezing temperatures cause long-term problems in any of these?
 

JimDawson

Global Moderator
Staff member
H-M Platinum Supporter ($50)
Joined
Feb 8, 2014
Messages
7,048
Likes
5,247
#2
With the insulation that you have, I would say a small electric heater might be practical to leave on during the cold weather just to keep the shop above freezing. Maybe 1.5 KW or so. Then when you want to work in there about a 50K BTU propane heater would warm it up quick, maybe one of the radiant types that are designed to operate in a closed space.

We don't have weeks of really cold weather so I don't heat my shop (1200 sqft), and I'm not insulated near as well as your shop is, but when it's cold I fire up my 150K BTU propane torpedo heater and point it directly at the machines from about 10 feet away to get them warmed up before I run them. Maybe give it a couple of hours to warm the machines up until they are warm to the touch. If I'm going to be in the shop for extended periods, then I fire up the wood stove. I leave the computers & DROs on all the time.

Storing measuring tools at low temperatures won't hurt them, but don't try to use them when they are really cold. You could keep the tools in a tool box and bring them into the house. I keep some of my precision tools in the house during cold weather. At the temperatures you are talking about humidity is not going to be a problem.

Petroleum based oils & solvents won't be affected by cold weather, any water based solvents and cutting fluids could freeze or separate if cold enough.

The biggest problem we have here is an extended period of cold & dry, then a quick warm up with high humidity. Everything sweats, so when I know that it is going to warm up like that, I fire up the wood stove to dry out the shop.
 

ThinWoodsman

Newbie
Registered
Joined
Jul 8, 2018
Messages
10
Likes
2
#3
Yeah, I know all about humidity - left for a week in August and came back to not only rust, but mildew growing on the just-installed walls of the shop. Bought a dehumidifier that's plugged into a timer to run it for an hour in the afternoon and an hour in the early morning. Seems to have solved the humidity problems.

Re: petroleum-based products and measuring tools: that is what I suspected, but I'm hesitant to ruin a gallon jug of way or circulating oil. For the measuring tools I was worried about metal creep due to the repeated warming/cooling (if shop is not heated 24/7), but looking into it more it appears that would be due to the small size of the devices and the relatively low temperature they'd be raised to (~60F).

For the first winter, I think I'll leave some consumable (read: cheap) dial indicators in the shop, along with filled oil cans. The expensive instruments and the gallon jugs of oil can be stored in the house until I can verify, come spring, that nothing got ruined.

Good idea on doubling up the electric and the propane/kero heaters. I may give that a go.
 

Bob Korves

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Jul 2, 2014
Messages
5,499
Likes
5,820
#4
Flame heaters that run on hydrocarbon fuels (gasoline, oil, kerosene, propane, natural gas, etc.) react with oxygen in the air when they burn. The result is that large quantities of H2O (WATER) is produced along with with the heat. With an heater that is not externally vented, the shop will be dripping with moisture, especially when it cools down again. Opening a door or similar helps some, but by no means completely, and also lets your precious heat go out the door or window. If there is a way of installing a chimney, you will be much better off when burning fuels in your shop. Electricity works great in a closed room, no fumes, no cold air coming in to burn the fuel, and no energy going up the flue. Depending on costs in your area, the price of electricity can be quite high or pretty reasonable in comparison to burning fuels. Efficiency numbers and cost of installation and fuel must be factored in to figure out what is best for your situation.
 

T Bredehoft

Active User
H-M Supporter - Gold Member ($25)
Joined
Dec 27, 2014
Messages
2,663
Likes
2,053
#5
From personal experience, one may work comfortably in an indoor shop with the temperature near or above 45ºf. Sure, you gotta dress for it, but you don't start chattering. If you could maintain that temperature with an electric heater, You could go to work and turn up the heat for a warmer place after a while. Or, keep it at that temp.
 

Karl_T

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Oct 14, 2014
Messages
1,021
Likes
429
#6
Once that concrete floor freezes solid, its dam near impossible to get the shop warm. Been there done that in Minnesota. I suggest radiant heaters, either electric or propane, use them to keep you warm. Works pretty well if you are running the lathe or mill. Not so much if you need to move all around the shop. before I got my heated shop, I also just gave up for about six weeks in mid winter.
 

gi_984

Active User
H-M Supporter - Gold Member ($25)
Joined
Dec 13, 2012
Messages
429
Likes
101
#7
Been there done that. Second the problem with the block of ice called the concrete floor. If at all possible keep it at 40 to 45 degrees ambient inside the shop all the time. Tried to use the kerosene torpedo heaters and the high end Kero Sun kerosene radiant heaters. Fumes to choke you out and stink. Plus it took forever to get the temps up. The circulating oil in the machines was the consistency of molasses. The machines just stayed cold even when the air temperature in the shop warmed up enough to work comfortably. Rapidly became not worth the effort once it truly got cold. My only regret with going to a fully insulated shop and heat was waiting so long to do it.
 

Dabbler

Administrator Trainee
Staff member
H-M Supporter - Gold Member ($25)
Joined
Oct 11, 2016
Messages
524
Likes
387
#8
It is good to cover the entire floor in an insulating material. The 2' X 2' basement tiles that are OSB bonded to styro work very well. place them everywhere, and your heating bill will be lowered by more than the cost of the tiles.

I used to keep my shop heated to 5C (41F) but now I do it to 8C (47ishF). I can work on the machines after only a little heating of the air in the shop, and the condensation has gone waay down...
 

hman

Active User
H-M Platinum Supporter ($50)
Joined
Feb 17, 2013
Messages
1,749
Likes
1,364
#9
... and even when cold, such a floor will draw a HECK of a lot less heat from your feet!

[edit] - Don't have the problem myself here in Arizona, and we live in a well drained area, so the anticipated heavy rainfall from the remnants of Rosa will not be a problem. But I used to have a garage/shop in Oregon. Covered much of the floor with interlocking foam mats. I can certainly appreciate the value of your solution!
 

uncle harry

Active User
Registered
Joined
Aug 19, 2013
Messages
677
Likes
397
#10
From personal experience, one may work comfortably in an indoor shop with the temperature near or above 45ºf. Sure, you gotta dress for it, but you don't start chattering. If you could maintain that temperature with an electric heater, You could go to work and turn up the heat for a warmer place after a while. Or, keep it at that temp.
Latex gloves (thin ones) keep fingers warm by avoiding perspiration evaporation cooling. My assistant friend & I use small ceramic electric heaters to warm our feet when working in one spot while waiting for the furnace or wood stove to catch up depending on which shop we are in.
 

Janderso

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Mar 26, 2018
Messages
768
Likes
455
#11
Dang, I have never had to deal with temps that cold.
It seems like the infrared style gas people heaters would be the most efficient and affective.
That’s what we use at the dealership. Each stall has a people heater above their work area.
Cold to us is in the 30’s and 40’s though.
 

NortonDommi

Active Member
Registered
Joined
Nov 15, 2016
Messages
312
Likes
195
#12
Just spring here and I'm going to sound like a wimp since the coldest it gets is about 1 degree C [34F]maybe overnight but high humidity and those Southerlies are straight off the Alps. By next winter I intend to have a couple of the newer infrared heaters with variable output. The one I bought was an outdoor model and needed to much clearance so I gave it to a friend with 5500 square feet of shop. It is mounted high up and works on his workbench area. Very pleasant underneath and all the tools are warm like they were in the Sun so no cold fingers. I like these as they warm objects and then the objects radiate heat which stops condensation. There are a lot of waste oil burner designs around as well which blast heat out. I can't even imagine the temperatures that seem normal to some of you.
 

magicniner

H-M Supporter - Silver Member
H-M Supporter - Silver Member ($10)
Joined
Oct 21, 2017
Messages
415
Likes
377
#13
Put insulating floor matting down to cover all areas not occupied by heavy machinery and run a dehumidifier, use a timer for On/Off periods as necessary.
That will keep the temperature up and remove the water you add to the shop.
 

CluelessNewB

Active Resistor
H-M Supporter - Gold Member ($25)
Joined
Mar 3, 2013
Messages
1,106
Likes
612
#14
I have an externally vented Modine "Hot Dawg" for my shop. It costs a bit more than a portable but doesn't add additional humidity and there is no need to keep a door or window open. My last shop had a wood stove which worked ok also. The propane is a bit more convenient and allows me to keep it heated for a few days unattended if required for things like paint drying. I do miss the wood stove at times.

https://www.modinehvac.com/web/prod...-heaters-hotdawg/hot-dawg-power-vented-hd.htm
 

magicniner

H-M Supporter - Silver Member
H-M Supporter - Silver Member ($10)
Joined
Oct 21, 2017
Messages
415
Likes
377
#15
There's no point having externally exhausted gas heaters in a shop where you allow humans to breathe out ;-)
 

Dabbler

Administrator Trainee
Staff member
H-M Supporter - Gold Member ($25)
Joined
Oct 11, 2016
Messages
524
Likes
387
#16
I have a gas heater in my shop that is ceiling mounted, much like a Hot Dawg; It keeps things quite dry and cool, but not too cold. I have a 50,000 BTU unit for a 650 Sq Ft garage. I insulated it to R12 in the bad old days; now I am reconsidering putting much more in.

My shop floor is only partially insulated as well, something that will get fixed this winter!
 

NortonDommi

Active Member
Registered
Joined
Nov 15, 2016
Messages
312
Likes
195
#17
Put insulating floor matting down to cover all areas not occupied by heavy machinery
That friend I gave the heater to I also delivered several truck loads of off-cuts from a wood supply company. These were 4" x 2" of assorted small lengths when timber was cut to length and any blemishes removed. I thought I was supplying firewood but he used them to lay down a Parquet floor over the concrete slab, all except for an area where stuff like bulldozers or other vehicles go to be worked on. Glue was the only cost and it is great insulation, very hard wearing too.
 

hman

Active User
H-M Platinum Supporter ($50)
Joined
Feb 17, 2013
Messages
1,749
Likes
1,364
#18
Just spring here and I'm going to sound like a wimp since the coldest it gets is about 1 degree C [34F]maybe overnight but high humidity and those Southerlies are straight off the Alps.
OK. Now please educate this geographical ignoramus. Which Alps are you talking about? Surely not the Swiss Alps (which are on the far side of the Equator)????
 

NortonDommi

Active Member
Registered
Joined
Nov 15, 2016
Messages
312
Likes
195
#19
Hi hman,
Southern Alps which run up South Island. Some days in Winter the wind comes up from Antarctica and travels up along the Alps, across the straight then hits a couple more mountains and goes through my bones like an ultrasonic razor-blade. One of those lazy winds that goes through you not around you. Here's a You Tube of a helicopter flight from a station to Milford. Good hunting grounds.
 

ThinWoodsman

Newbie
Registered
Joined
Jul 8, 2018
Messages
10
Likes
2
#20
Yeah, I've had plenty of suggestions from neighbors on heating the space - most of them just went all-in and installed a vented heating system for their detached workshops.

For now, I'm okay with abandoning the shop during sub-zero temps, as I still have a basement shop to work in, and that stays above freezing.

I'm more worried about damage to machines/instruments/materials caused by exposure to these temps, but as Jim Dawson mentioned this is likely to be negligible. Cold storage it is, then.

EDIT: I did purchase a small electric oil-filled (radiant) heater and will be using that to keep the space above freezing until it can no longer keep up. I'll try to remember to update this with how it worked out in around Feb.

Thanks, all.
 

Boswell

Hobby Machinist since 2010
H-M Platinum Supporter ($50)
Joined
Feb 27, 2014
Messages
619
Likes
278
#21
I did purchase a small electric oil-filled (radiant) heater and will be using that to keep the space above freezing until it can no longer keep up. I'll try to remember to update this with how it worked out in around Feb.
I also use a oil-filled radiant heater. I have an insulated shop with exposed concrete floors. I put the heater on the floor behind my lathe and it does not take up any otherwise usable floor space. Keeps the shop very comfortable in the winter.
But of course I am in Central Texas and while we do get a some days each year below freezing it is rarely very many so this work to keep the shop comfortable. The exposed concrete is so it will help keep the shop cooler in the summer which is much more of a concern.
 

ThinWoodsman

Newbie
Registered
Joined
Jul 8, 2018
Messages
10
Likes
2
#22
"For optimal storage, maintain product at a
temperature between 8°C (46°F) to 21°C (70°F). Storage
below 8°C (46°F) or greater than 28°C (82°F) can adversely
affect product properties. Cyanoacrylate products must be
stored under refrigerated conditions at 2°C (36°F) to 8°C
(46°F). Storage below 2°C (36°F) or greater than 8°C (46°F)
can adversely affect product properties."

Looks like the Loctite will get kept in the house.
 

Karl_T

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Oct 14, 2014
Messages
1,021
Likes
429
#23
...

I'm more worried about damage to machines/instruments/materials caused by exposure to these temps, but as Jim Dawson mentioned this is likely to be negligible. Cold storage it is, then...
I suggest you get a Sureshot sprayer. Fill it with motor oil thinned with diesel. Spray all the metal surfaces. Stops rust and is quick to apply.
 

eugene13

Active Member
Registered
Joined
Nov 19, 2014
Messages
298
Likes
287
#24
Mobilmet soluable oil should not be allowed to freeze.
 

ThinWoodsman

Newbie
Registered
Joined
Jul 8, 2018
Messages
10
Likes
2
#25
I suggest you get a Sureshot sprayer. Fill it with motor oil thinned with diesel. Spray all the metal surfaces. Stops rust and is quick to apply.
Yup! Been doing that since the problems with humidity this summer. Beats the pants off using a brush - those sureshots are great. Gave it a go applying way oil to the lathe after its first real cleaning - results were a bit mixed (ways oiled very quickly, but with too much oil).
 

ThinWoodsman

Newbie
Registered
Joined
Jul 8, 2018
Messages
10
Likes
2
#26
Mobilmet soluable oil should not be allowed to freeze.
Thanks for mentioning that - I don't use S-122, but it reminded me to check up on the cutting fluids I use. The Oatey dark cutting oil is fine, of course, but the SDS for Tap Magic (Aqueous) lists its freezing point as 32F and includes "do not freeze" on the storage requirements.

Between that and the Loc-tite, it looks like an evening of downloading SDS PDFs is in order. Only way to be sure.
 

Downunder Bob

H-M Supporter - Sustaining Member
Staff member
H-M Platinum Supporter ($50)
Joined
May 16, 2016
Messages
956
Likes
384
#27
I don't know how you people live in those below zero temps. A pity you didn't put some hydronic water pipes in the concrete slab when it was poured. I imagine your barn has quite a high roof, so you could raise the floor level and put some pipes in as you do it, then set a thermostat at say 5c for standby and just add some extra heat when you're in the shop, A flued propane or wood burner, or electric whatever suits.

Even in Australia where I live the midwinter min is rarely ever below about 5c my garage shop is heated to 15c by a hydronics setup running of a wood burner, that heats the whole house to around 22c. So condensation is never a problem, and I can work in the shop with only a light jacket over house clothes.
 

eugene13

Active Member
Registered
Joined
Nov 19, 2014
Messages
298
Likes
287
#29
I did, and I heat with Coal, both the house and shop. We have a humidifier in the house but my shop is dry, no problem with condensation or cold.
I don't know how you people live in those below zero temps. A pity you didn't put some hydronic water pipes in the concrete slab when it was poured.
 

Downunder Bob

H-M Supporter - Sustaining Member
Staff member
H-M Platinum Supporter ($50)
Joined
May 16, 2016
Messages
956
Likes
384
#30
We haven't been allowed to use coal here for as long as I can remember, but we do use wood, mostly red gum, also known as Red River gum, Eucalyptus camaldulensis about the best firewood you can get. It's an Australian native, but now grown all over the world, mostly for firewood. I've even read that in Brazil they use it for smelting steel.
 
[6]
[5] [7]
Top