Heater inside the trailer for fiberglass work

[bartek]

I'm about to get to the point where I'd be applying epoxy/fiberglass on my trailer. Unfortunatelly I live in WA and it's quite cold outside atm.
After turning on all the heaters I own and opening the door between the house and the (poorly insulated) garage, I can barely get the temperature up to 60F.
I'm planning on using Raka 127 epoxy and their non-blush hardener, which states 60F as min temperature (and from what I read, more would be much better since I'm after clear woody finish)

Has anyone tried putting the electric heater inside the trailer? My thinking would be that I can get it to heat up the air inside quite well, and it should eventually transfer to the walls/roof warming up as well, but I don't know if the colder air temperature around it is going to be a problem.
I also don't know if I really get the outside of the walls to heat up enough, although I suppose that part will be easy to test

Alternatively, I can try to get one of the tube propane heaters, but I'd like to avoid buying this for one time use, and I also heard they increase moisture content in the air (and it's already wet enough here with constant rain )

[working on it]

from the thread
Re: How cold is too cold? http://www.tnttt.com/viewtopic.php?f=65&t=73183&hilit=+heater#p1269693

* I polyurethaned/painted my 4x8 at both extremes of the weather, at least for N.Texas...not Panhandle-type weather (it actually snows up there!). I used oil-based Min-Wax poly, mixed with thinner for my base coats, quickly followed with paint, at over 100 degrees in blazing sunlight, and also paint+thinner (no poly, except on the floor and along the bottom wall seams, since the exterior and both sides of the doors were already water-proofed with poly) between 80 and 45-40 degrees inside (even mixed with 25% thinner, it started to get thick below 40 degrees).

* I painted the interior in either Jan-Feb ?, using a small space heater to warm the interior up to 80 degrees or so (so the paint would adhere, and cure). I had to paint in stages, pulling the heater out while I was inside, and stopping the painting when the temperature dropped inside below 45-40 degrees. Then, I would re-heat until I could resume. Took me two days, over two colder weekends. I didn't mind the fumes (I used to build Military models in a small, closed room in the 50's-60's..."smells like Victory!"). But, a word of caution; don't wear your only good pair of glasses when painting a ceiling in a 4x8 trailer, only inches above your head. Dries quickly, and irremovable from plastic, coated lenses!

[Pmullen503]

An electric heater is what you want. As you correctly pointed out, propane tube heaters put a lot of moisture in the air. Any condensation at best will make the epoxy cure cloudy and at worst will make not cure well at all.

I use my foamy as a hot box for doing glass work on small projects with a small electric heater. You might be able to do the inside and tent the outside if you can get the temperature up high enough. I glassed a canoe under a tent decades ago using a dozen incandescent light bulbs(remember those) as a heat source.

[jgizzi]

We are from WA state as well, far NW corner in Ferndale ;-). We used the Raka epoxy, the 350 though, in our unheated garage when the outside temps dipped below 40 and didn't get above 55 during the day. We used two heat lamps and tented with a tarp and all worked great. This cold patch has me worried a bit as we are about to do the roof but I figure with two heat lamps inside we will transfer enough heat to cure.

I sounds like you have enough heat to not worry. 60 degrees should work fine. Good luck!

[Bezoar]

I'm in same boat - I have a detached shop here in WI, but the high yesterday was 2 degrees F. I have propane heat and usually keep the shop at 40 when not in it, bump it up to work in there. I want to do RAKA epoxy on the road side of my floor, but was wondering what temp I needed. I guess I'll set it at 65 while curing and give it a whirl. Maybe not ideal conditions for first time epoxy learning!

[Tom&Shelly]

I'm in same boat - I have a detached shop here in WI, but the high yesterday was 2 degrees F. I have propane heat and usually keep the shop at 40 when not in it, bump it up to work in there. I want to do RAKA epoxy on the road side of my floor, but was wondering what temp I needed. I guess I'll set it at 65 while curing and give it a whirl. Maybe not ideal conditions for first time epoxy learning!

I just did a small job with RAKA epoxy on Friday with the shop in the mid-60's, brought it upstairs on Saturday (and I appreciate that's not an option for your job) where it varied from low 60's at night to about 70 in the day, and it took three days for the left-over in the pot to cure hard. Just takes some patience.

I often run the electric heater overnight in the Winter when doing epoxy. Portable heaters and the old fashioned incandescent lights providing spot heat on the project also help. You may want to consider turning your propane heat up a notch. There is a big difference in cure time between the high 60's and low 70's.

Tom

[bartek]

It warmed up here a little bit last week, and I managed to get the garage up to 65F. No problems with the cure - comes out clear (and where it doesn't it seems like a technique problem) and seems well cured after 24h.

I borrowed two infrared dishes from a friend, and they seem great to heat up individual surface which is being worked on - in experiments, I can get the temperature of the teardrop wall to well over 75F.
I ended up not using it though, as it would force me to work in sections and I was also worried about the impact of potentially uneven temperature - these things seem to focus heat on a very specific spot, and I can't place them far enough to distribute the heat a little better.
If you had the option of moving them a little further from the wall and was ok doing one wall at a time, it seems like it would be a great and economical option though.

For what is worth, I threw a cup of leftover epoxy outside (40F or so) and it seemed to have cured fine too - I can't comment on the strength of the cure or whether the finish would be clear (the cup was full of bubbles, so it came out completely white as expected)

[Tom&Shelly]

For what is worth, I threw a cup of leftover epoxy outside (40F or so) and it seemed to have cured fine too - I can't comment on the strength of the cure or whether the finish would be clear (the cup was full of bubbles, so it came out completely white as expected)

It surprises me that that cured. We applied some epoxy to something in our 45-50 degree Winter shop a few years ago and it took a week or more to cure. We had three lights on it with 100 W incandescent bulbs. That's what convinced us to buy an electric heater for the shop; I was fine doing woodworking in a sweater in the Winter.

Tom

[OP827]

For what is worth, I threw a cup of leftover epoxy outside (40F or so) and it seemed to have cured fine too - I can't comment on the strength of the cure or whether the finish would be clear (the cup was full of bubbles, so it came out completely white as expected)

It surprises me that that cured. We applied some epoxy to something in our 45-50 degree Winter shop a few years ago and it took a week or more to cure. We had three lights on it with 100 W incandescent bulbs. That's what convinced us to buy an electric heater for the shop; I was fine doing woodworking in a sweater in the Winter.

Tom

I am late to this discussion, but I did a lot of gluing and epoxy works inside my trailer when it was too cold outside for epoxy or glue to cure, like freezing cold. A basic 120V electric heater raises inside temperature very quickly. I would avoid using propane heater as it will cause epoxy to blush due to moisture introduced in the air (propane burning reaction products are H2O and CO2) as already mentioned here.

As for a surprise with leftover cured while at low temperature, we all know that epoxy curing reaction creates heat and when small leftovers are left in a cup and not spread it will continue curing if the heat is not dissipated vs. a surface application for lamination.

[OP827]

It warmed up here a little bit last week, and I managed to get the garage up to 65F. No problems with the cure - comes out clear (and where it doesn't it seems like a technique problem) and seems well cured after 24h.

I borrowed two infrared dishes from a friend, and they seem great to heat up individual surface which is being worked on - in experiments, I can get the temperature of the teardrop wall to well over 75F.
I ended up not using it though, as it would force me to work in sections and I was also worried about the impact of potentially uneven temperature - these things seem to focus heat on a very specific spot, and I can't place them far enough to distribute the heat a little better.
If you had the option of moving them a little further from the wall and was ok doing one wall at a time, it seems like it would be a great and economical option though.

For what is worth, I threw a cup of leftover epoxy outside (40F or so) and it seemed to have cured fine too - I can't comment on the strength of the cure or whether the finish would be clear (the cup was full of bubbles, so it came out completely white as expected)

One lesson I learned is to apply heat before putting epoxy on the surface, not after especially avoid using infrared radiant heaters pointed on the surface after application. Area fan heater works safer. I did this mistake by applying radiant heat to a laminated surface after epoxy was applied and it caused the air inside wood and foam to expand from the heat and lift to the surface, creating small bubbles and even glass cloth to lift off in some places. Just sharing my learning experience here.

[Pmullen503]

+1 on prewarming the surface.

On infrared heaters. Epoxy has excellent absorption of IR energy. So they can be very useful for epoxy work in cold weather. But it's easy to get the wet surface too hot and get bubbles. A non contact thermometer gun is almost essential.

BTW, epoxy is has excellent absorption of microwave energy too. I have an old microwave in the shop for warming epoxy. As little as 10 seconds will raise the temp of a few ounces by 20 degrees.
But it doesn't penetrate very far. So blast it for a 5 or 10 seconds, stir and blast it again. Do that a few times and you can quickly get cold epoxy up to working temps.

[OP827]

+1 on prewarming the surface.

On infrared heaters. Epoxy has excellent absorption of IR energy. So they can be very useful for epoxy work in cold weather. But it's easy to get the wet surface too hot and get bubbles. A non contact thermometer gun is almost essential.

BTW, epoxy is has excellent absorption of microwave energy too. I have an old microwave in the shop for warming epoxy. As little as 10 seconds will raise the temp of a few ounces by 20 degrees.
But it doesn't penetrate very far. So blast it for a 5 or 10 seconds, stir and blast it again. Do that a few times and you can quickly get cold epoxy up to working temps.

I did not know that, Thanks!

[KCStudly]

Re: surplus pot curing in cold. According to Westsystem, in marginally cold weather they recommend a little more pot time to get the reaction to start before laying out thin (either in application or transferring to a tray to increase working time). Once the chemical reaction starts it won't stop, but if it doesn't start right away, or is never given enough heat, it will take longer. Perhaps much longer.

So by mixing in (just) suitable temperature conditions and leaving enough mass together for a while before moving it to cold, it probably didn't matter that it went from warm enough to too cold.