With the understandable shipping delays, likely my MR1 won’t arrive in Canada until December or so. It’s already way below freezing here and I’m worried the epoxy product supplied to coat the concrete will be frozen solid. I’m told that if that happens, the product will not cure properly. Basically it will stay tacky and not harden. That will be a major problem. Anyone else worried about this?
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I am worried about this. But I do have a kiln in my garage that gets it up to 30C in short order. So long as it’s not minus 20 outside.
Likely some others will have to hold off on epoxy if they can’t find a heating solution for the 24 h or so.
I too am a little worried. What about freezing temperatures during shipping?
As it sits in trucks overnight somewhere, how will the epoxy be affected?
I don’t know if that is a problem before mixing.
Any thoughts there?
It’s not as sensitive to cold temps unmixed. I’ve had a tub of epoxy and hardener outside in the garage while it got fairly cold minus 2 or 3 degrees C outside and it was fine. It has a decent amount of thermal mass so cold night time temps will likely not freeze it. Also it’s not water so the freezing point is likely less than zero.
I wouldn’t worry too much. Worst case scenario we will order a new tub locally from plasticworld.
Mo
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I couldn’t find anything on the ProMarine web site that specifically addresses freezing prior to mixing, but it appears that most epoxies are fine if they freeze prior to mixing as long as they are brought back to the recommended temperature. Which is ~75 degrees F (~24 C) for the ProMarine epoxy supplied by LS.
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I do a fair amount of epoxy work (tables, inlays, etc) and can confirm that.
You may get crystallization even after bringing it up to room temp but immersing the containers in hot water for an hour or two should clear it.
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I called ProMarine and they said the same thing. Only thing to add is let it cool back down to ~75 degrees F (~24 C) after the hot water bath before mixing.
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Thanks for all that info! Good to know.
I’ve had other fluids freeze and they never seemed to set up right afterwards.
This is good news! It is 5 degrees F here this morning so I’m not going to be out in the shop yet anyway . . .
I am in San Diego and tried to do my epoxy pour on a sunny 68F day. The epoxy was cold from sitting in the garage over night (50 F) during the initial paint on phase. I did warm up parts A/B throughout the day for the final pour at 4pm. All went well but now after 3 days there are spots where it is still sticky. I know in colder weather it takes longer but not sure what to do at this point. Tried to air my garage out on the day of the pour and the day after. Any tricks to get the last weird spots to harden up or just wait longer? I did make a really good effort to mix it thoroughly by scraping all sides and bottom during the 3 minutes mix time. Thank you for your help.
Jeff
Get a space heater and have it direct hot air at the surface for several hours or you can create a tent of some kind and heat the tent with a space heater or heat gun, just want to keep the temps below 120-140 F or so. Some epoxies go much higher but I’m not sure about this one.
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I assume you mixed the epoxy really well? BTW your temps are balmy compared to what some of us are dealing with lol.
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Yes, I mixed it really well and had some left over so I wasn’t scraping the bottom or anything. I will throw a space heater in there for a while and try to get things warmed up. Thank you for the fast reply. I did just go to the pro marine website and see the 75 F, but I just don’t see how anyone could maintain that for the drying period especially with others already completing this step in much colder conditions than I have here.
yeah hard to say what couldve gone wrong but i would definately try to get it to 90+ for a couple hours to get those soft spots tacked up. Worse comes to worse you will need to sand/ scrape it off and repour the spot or for best looks sand everything and repour another coat on top.
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ohh, another San Diego person 
Ya, there is a bunch of us out here.
We’re expecting Sunny and 80 degrees for Christmas Day 
Marry Christmas everyone.
Bob
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Just an fyi. My first attempt at the epoxy pour failed. I was left with a sticky/tacky surface in some spots and a large part that was gummy. I too let the temp drop in my shop during the first 24 hrs. The majority of my problems (in hindsight) were due to improper mixing technique (i.e. used an intermediate measuring bucket). Anywho… after tearing up the first pour I did a second… also with a sticky surface… scraped and sanded it and did one last pour. This time had two space heaters and kept the temp above 75 degrees in my garage (approx 40 degrees outside) for the full 72 hours. Third time’s a charm… Epoxy looks great now. * Side note… I filled in the space created between the Y-axis stiffeners and the y axis uprights with some black foam core board. Kept the epoxy from draining into those areas and making low spots on the other wise level surface.
Foam core insert
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I had below optimal temps when I did my pour as well (50’s). I think the critical thing is to maintain the temperature of the concrete, not the ambient temp in the shop.
The concrete slab is too large of a thermal mass, and if not heated will suck the heat right out of the epoxy. I placed a propane space heater under the base and measured the surface temp of the concrete with an IR temp gun until I got into the mid to high 70’s (moving the heater around occasionally to prevent hot spots). After the pour, I maintained the temp of the concrete with the propane heater during the day as needed and electric space heater at night for 48 hours. The shop temp still got into the 50’s over night, but the concrete and epoxy maintained high 70’s to low 80’s.
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If the epoxy is mixed correctly temperature wont ruin it alone, it will just extend the cure sometimes indefinitely. Once heated it should have no problem curing given excessive moisture hasn’t accumulated.
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I flood coated yesterday and the day before. Temps dropped to 8° last night and we have a good cure today.
One of those particle board panels from the shipping crate, I set over the Y rails and had two space heaters blowing into the space.
My internet and cell service have been messed up all day, but this photo was taken at about noonish and 5pm would be 24 hours.
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Meanwhile I did something similar but poired epoxy to make a higher area inside that void under the Y-axis rails…