Epoxy in cold weather (ie now in the UK)

[wombat88]

I need to use some epoxy to glue in plugs over recessed screws and a couple of small patches of tissue over dodgy areas of my boat.

I'd rather the patches of tissue did not go milky (is this called blooming?)

How low can the temperature be? I have heard 10 degrees C mentioned...

 

[Poignard]

Advice I had from Wessex resins was that if the work area is warm enough that you'd be comfortable in a T-shirt (plus trousers) then it's OK for epoxying. If not, you need extra heat.

 

[dankilb]

This is a tricky issue and I'm intrigued to hear the responses - probably ranging from 'no problem - go for it' to 'don't even bother'! My few thoughts would include:

1) It depends which epoxy. West 105/205 (fast hardener) provides data down to 5 degrees (but in reality, you might struggle at that sort of temp). Other brands I've used state clearly not to go below much higher temps (10 or even 15 degrees) - but I can personally attest to experience of getting them to cure successfully significantly below those sort of temps...

2) It isn't just about temperature. I've only encountered the sorts of blooming you mention that actually prevented the work curing once or twice - but this was at temperatures comfortably above the minimum (say around 10 degrees) but when there was a lot humidity in the air (think those dank December days). On one occasion, I tried again the next day - which was colder, but drier - and the same repair cured successfully.

3) Use heat! You can use halogen or infrared heat lamps to warm the area. That's what the do in many UK boatyards. You can also heat the resin - which I routinely do in colder temps, just to improve workability. But be careful, there are various risks of setting your boat on fire doing this!

I'm 3 years into a refit requiring very extensive epoxy-based glasswork (to the tune of dozens of gallons now consumed) and have so far succeeded in getting all required jobs to cure, when I was desperate, in some pretty grotty UK conditions. But you do have to accept this is very far from ideal and can easily fail. It's not the end of the world - clean up, re-assess and start again. But expect some posts below to categorically tell you 'it won't work!' and heed those as probably based on painful (disappointing, messy, expensive!) experience. But where there's a will...!

 

[SvenH]

I've used standard 15 degree epoxy in mildly freezing conditions, heating the area with a 300 watt halogen worklight.
It was too close at around 40 cm, epoxy started releasing smoke....

 

[dankilb]

Advice I had from Wessex resins was that if the work area is warm enough that you'd be comfortable in a T-shirt (plus trousers) then it's OK for epoxying. If not, you need extra heat.

I finished the last big (large format / structural / expensive!) epoxy-glass job of this year just a couple of weeks ago. It was definitely colder than t-shirt weather, despite the unseasonal temperatures (NW England). I did need to heat the resin (otherwise it would've been a nightmare to wet out) but not the work area (lazarette locker so essentially 'outside'). All work cured perfectly with little more amine blush than usual/summer conditions (and no 'cure preventing' blooming at all).

I've used standard 15 degree epoxy in mildly freezing conditions, heating the area with a 300 watt halogen worklight.
It was too close at around 40 cm, epoxy started releasing smoke....

Great point this! The only times I've 'cooked' epoxy in recent memory were in the depths of winter using a heat lamp.

 

[srm]

Depends on the epoxy and the type of hardener. West System have two or three different hardeners for different temperature ranges and I used the 10C plus hardener in the far north of Scotland.

"If in doubt read the instructions"

 

[dankilb]

(Like everything he does...!) This recent video from Andy in the US was very informative on cold weather glass/resin work and mirrors my experience exactly. He focuses a lot on the risks of overheating the work area. It isn't just focused on epoxy, but the same tricks/considerations apply. His conclusion = with care, it's entirely possible!

 

[vyv_cox]

Many times in North Wales in winterI have built simple boxes from polyurethane or polystyrene foam, heated with a 60 watt light bulb. Epoxy goes off nicely inside.

 

[Keith 66]

Years ago i bought a 1.5Kw Red Rad infra red lamp, It is a powerful beast & must be treated with respect, I have fibreglassed outside at Halcons yard in a snowstorm in February & the resin cured perfectly.
I rarely use it these days but bought a 250w Poultry lamp last year, available on amazon for under 40 quid, it has high & low heat settings & is adequate for small jobs or when space is limited.
I would not attempt to use epoxy in weather like we have at the moment without it.

 

[Daverw]

I heat the resin before mixing and then warm the area, seems to work as long as it’s not also blowing a gale or going to go low to a frost

 

[Stemar]

205 Fast Hardener
Minimum recommended temperature: 40°F (4°C)

205 Fast Hardener

Just don't try and use it for a big job in the summer!

 

[wombat88]

So...heat is needed.

General consensus is that fast hardener works down to around 4-5c but as you say is not much use in the summer.

My conclusion is that if I am worried about it wait for warmer weather. Epoxy and hardener are far from cheap and nor is electricity this winter.

I have ended up with a sticky mess before and don't want to repeat the experience.

Thanks all.

 

[Stemar]

Not necessarily.

205 Fast Hardener
Minimum recommended temperature: 40°F (4°C)

205 Fast Hardener

Just don't try and use it for a big job in the summer!

I used this last winter and it does work - though, obviously not if it's really cold

 

[neilf39]

I have successfully epoxied between 5 and 10 degrees C using medium and fast hardener. Keep free of moisture/condensation.