Epoxy work in colder weather

[ktm_2000]

Hi All,

Life has been getting in my way for the last several weeks and I haven't got much done on my project, crazy work, family events, sick kids, me sick from taking care of sick kids, etc. I'd love to keep on working on it but am afraid of doing poor quality work due to cold weather only to have to rip it all out and do it over again. I've got my transom core in but not glassed, bulkheads cut out needing to be permanently installed etc. All work to be done with glass and epoxy.

I have my boat shrink wrapped and can get electricity out there and was planning a few tactics like switching to fast cure hardener, warming resin, heating the boat for a few hours prior to work, partitioning off a section of the boat with tarps to reduce the sq. feet the electric heater has to heat.

I'd like to know what strategies folks have used in the past, which ones worked and which ones didn't?

[CamB25]

Thoughts:
- follow the mfg recommendations
- keep your materials warm until immediately ready to use
- fast cure hardeners can help.
- cold cure epoxy - https://www.systemthree.com/products/co ... ther-epoxy
- Work on pieces/parts in a heated shop. I built "modules" in my heated garage over the winter months - forward seating, transom seating, center console, seat base, wood stuff, etc.

Cam

[John F.]

I do most or almost all of my boat/epoxy work in the winter. I live in MD so our winters aren't as cold as yours. Like Cam mentioned, when I can, I build and lay up component pieces in the garage. When I do stuff in the winter on the boat, I try to pick warmer days/nights, and use heat lamps for the cure. I pretty much always use fast-cure epoxy. I think West will cure down to 45 degrees. I try to stay away from electric heaters if I'm going to be away from the boat. Whether I'm doing work in the garage (still cold, but I heat with a kerosene heater and use heat lamps), or down at the boat, I move the resin and hardener into the house the night before so its at room temp when I want to mix. If you forget, you can put the resin and hardener under heat lamps to get them warmed up so they can be mixed. If for some reason you miscalculate the weather, and its colder than you thought it would be, the epoxy will stick kick if you get a heat lamp on it. Don't go crazy with the heat lamps though, and be careful with them. If they tip over, they can cause a fire almost as easy as an electric heater. Good luck.

[Bruce]

My dad's first boat was a 27 chris craft wood. First winter in Philly he had it parked in the driveway, built an A frame structure around it, cover with heavy plastic and used a kerosene heater to heat it. Did a bunch of rotten wood/epoxy work.
He sprayed something on the outside he got from his development lab so the snow wouldn't stick.

[Tony Meola]

When we repowered, the Fiberglass shop that did some of the glass work for me, worked outside and did glass work in January. The boat was tented with shrink wrap. I don't remember him using heaters.

When I asked about curing he said it is all in the mix and that it would kick and not be an issue. It is now 10 years later and it looks like the day he did that portion of the work.

Not sure how he mixed it and unfortunately he passed away so I can't ask. Check with the fiberglass supplier. If they supply glass shops they should know how to make it work.

[ktm_2000]

several of you have expressed concerns with electric heaters, what is the concern? is it the extension cord? and getting power out there cleanly and not tripping breakers. Or is it the heater?

I have a outlet in the garage and have @35' run to the boat so I need a 50' cord. I went to HD bought a small 1500 watt electric heater which has a thermostat and followed their chart on extension cords and got one size up from what they said would do 15 amps for 50' I think it was #12 wire, pretty expensive...

for the transom core I did a 500 watt halogen a couple feet off the wood. I left it on for 3 days with no issues. It was 60 during the day and 45 at night. I could feel the warmth of the setup by touching the outside of the transom. I'm a little concerned that it was fine for the temps that I was at but won't cut it as it gets colder.
https://photos.app.goo.gl/tLmKKHsdGj8x8RLq5

[John F.]

Tony

I'm pretty sure you can vary the mix of polyester, and get it to kick in colder temps by adding mek. With epoxy, the mix is the mix.

John

[Tony Meola]

John

I would still think if epoxy is laid up correctly it will still kick when the weather warms up. But then again just goes to show you what I know about glass work.

[Tony Meola]

https://www.clcboats.com/modules/shopti ... ld_weather

https://www.westsystem.com/instruction- ... e-bonding/

Looks like the answers are just an internet search away. Here are two links, hope they help.

[Pete Fallon]

ktm2000,
When I was building the 34 Legend we never did any glass work below 50 degrees we were in Hobe Sound and right on the freeze line on the East Coast of South Florida. Our building was a steel open sided 75 x150 with drop curtains for rain. If your using epoxy or FRP, all the parts should be above 50 for at least 2 to 3 days to get a good bond and electric heaters have a tendency to create hot spots and also if the power goes off your work will be ruined.
I would try and find a kerosene heater and keep a constant eye on any fire hazards near the kerosene heat source. I would wait to do any large areas until the weather warms in the spring. Small epoxy jobs under a well heated tent would be okay. But wait to do the transom.
Pete Fallon

[ktm_2000]

Pete,

While I don't like your answer because it will stretch out the timeline of my project, I agree with you that it is the right answer and need to wait.

The links that Tony Meola put up from west system cautions states that I probably could do the work in the temps that are around right now but if done wrong I'd probably be doing the work over again.

"One of the dangers in using epoxy in cold weather is that epoxy that has not cured completely will be more flexible. Testing clearly demonstrates that increased flexibility seriously reduces an adhesive’s ability to resist fatigue and creep-rupture. Information about fatigue, fatigue testing, and the how flexibility affects the fatigue life of epoxy, can be found in Fatigue Aspects of Epoxy and Wood/Epoxy Composite Materials (pdf)."

It also cautions on the use of kerosene heaters as well

"Avoid unvented open-flame heaters that burn kerosene or fuel oil. Unburned hydrocarbons have been known to contaminate bonding surfaces, and elevated moisture and CO2 levels may inhibit epoxy’s cure. Catalytic heaters do not appear to pose a problem unless they’re used in a confined space such as a curing tent or box."

I'm an amateur at this and don't want to push my (BAD) luck and would rather extend my project and get it done right.