West epoxy winter time

Rhylsailer99

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Having a nightmare as i need to epoxy fill and cloth some areas outside . When the daytime temps are great the night temps are usually low . Do i eally need to wait for high night temps if I epoxy in the morning when the day time temps are OK.
 

wombat88

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I think you do need a steady, honest 5 degrees and at that temp curing is quite long. At this time of year moisture might make it go milky too
 

Babylon

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I'd say you'd be fine if you waited until mid-morning when things have warmed up a bit (and dried off any remaining condensation from the night), as you'll have a good six hours or so before temperatures drop towards dusk.

But if you're worried, why not just do a test-run beforehand.

Going to have some quite nice weather over the next few days! ?
 

Boathook

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I have found that epoxy's seem to stop curing when to cold and then start up again as the temperature rises. If you are able to warm the area before hand plus keep warm overnight it does help a lot imho.
 

Poignard

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A tip I was given by a WEST/Wessex Resins adviser was the T-shirt test.

If it's warm enough to be comfortable with just a T-shirt on your upper body, it's warm enough to apply epoxy.
 

Rhylsailer99

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A tip I was given by a WEST/Wessex Resins adviser was the T-shirt test.

If it's warm enough to be comfortable with just a T-shirt on your upper body, it's warm enough to apply epoxy.
If that's true I guess I'll be waiting for a warm spell in April, I'll just do everything I need to do and make it the very last job.
 

TernVI

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As well as curing faster, heating the epoxy thins it, so it penetrates and sticks better.
Personally, I heat the work with a hot air gun, which also ensures the surface is dry.
Once the work is under way, keep it warm with whatever heater is available, halogen, fan, whatever.
I've seen a poly bag full of hot water used to good effect, to apply heat and pressure.
Overnight temperature does not matter much, because if it's not set hard in 3 hours, you are doing it wrong.

Pre-warm the epoxy before mixing by standing the cans in water at maybe 25 degC, or store in the house overnight.

Obviously big laminating jobs with slow hardener are a different game, but they need to be indoors anyway.
 

dankilb

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Yup - too soon for outside. You mustn't let it go below 5 degrees as the risk of not curing (and a sticky mess to clean up) is pretty well guaranteed.

Otherwise, yes, the warmer the better. But sticking within the temp ranges as a minimum (for the required time) will at least ensure it will cure - although it might be more viscous, harder to apply, etc.

Just the way it is, unfortunately. Unless you'd consider tenting and heating the area.
 

Daydream believer

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When I was sheathing the outside of my Stella hull with 300grm cloth & West epoxy resin the stuff was going off in 30 mins.It had to as the stuff was being applied on the underside of a clinker hull. I could have used a faster resin for cold weather. Are you sure that you are using the correct resin for fast curing in cold weather. I admit that it was not super cold, but the speed it went off would not have not been affected by evening temp. So an enclosure with a short term heater would be more than sufficient. Sometimes the heat from the curing epoxy melted the polythene container if I mixed too much at a time.
 

Rhylsailer99

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When I was sheathing the outside of my Stella hull with 300grm cloth & West epoxy resin the stuff was going off in 30 mins.It had to as the stuff was being applied on the underside of a clinker hull. I could have used a faster resin for cold weather. Are you sure that you are using the correct resin for fast curing in cold weather. I admit that it was not super cold, but the speed it went off would not have not been affected by evening temp. So an enclosure with a short term heater would be more than sufficient. Sometimes the heat from the curing epoxy melted the polythene container if I mixed too much at a time.
Yes fast cure. I'm sure it would go off in the day time but I read it needs a few days to reach full hardness and I just want to be 100% sure that would happen, with the current cold night time temps.
 

Rhylsailer99

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Yes fast cure. I'm sure it would go off in the day time but I read it needs a few days to reach full hardness and I just want to be 100% sure that would happen, with the current cold night time temps.
I'll just wait a few weeks as I don't think I am allowed out yet because Rhyl harbour you get stuck behind a bridge that needs lifting.
 

Rappey

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I did a lot of work on the exterior of my boat between November and March some 5 years ago. The boat did have a tarp over it.
I used fibreglass, epoxy , 2 pack contact adhesive ,various glues and paint and it was often only a few degrees. Didn't really have any problems but drying times were longer and paint was a little less fluid.
Less than ideal conditions but none of it has fallen off yet.
 

lloydlloyd

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If your desperate you could use duck tape and a cardboard box and tape it over the area. and place a a small heater in side to keep the temperature up.
Im not sure how large an area you need to work on is. or even if you have access to electricity.
maybe you can tape loads of boxes together or use a tarpaulin and a few more heaters.
But if their is a will their is normally a way.
Just depends on how far your willing to go for it.
Because we had to split are work shop into two to keep the temperature up when building the hull over winter.
We used a tarpaulin and loads of old mattresses we found on the side of the road to insulate the area.
and it worked great, and we where able to keep temp at 25 and above through the coldest nights this year.
we did have like 5 heaters in their.
 

thinwater

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All of this is good in theroy. In practice, pushing temperature limits increases the odds of all sorts of things going wrong. You gotta either wait or warm the area (in the cabin, for example) enough that it is mostly cured before you leave. But sometimes you can also warm the deck or hull by heating the inside the boat really warm , like 85F.
 

Mark-1

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Yup - too soon for outside. You mustn't let it go below 5 degrees as the risk of not curing (and a sticky mess to clean up) is pretty well guaranteed.

Otherwise, yes, the warmer the better. But sticking within the temp ranges as a minimum (for the required time) will at least ensure it will cure - although it might be more viscous, harder to apply, etc.

Just the way it is, unfortunately. Unless you'd consider tenting and heating the area.

I have a similar problem to the OP.

So is 5 degrees the magic number? I've got a few hours of 7 degrees today, and could potentially aim a heater at it but can't guarantee that.

And is the consequence of getting this wrong simply that it won't cure and I have to wipe it off and start again? (Which wouldn't be a drama.)

Cosmetics are not a concern here.
 

Birdseye

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Having a nightmare as i need to epoxy fill and cloth some areas outside . When the daytime temps are great the night temps are usually low . Do i eally need to wait for high night temps if I epoxy in the morning when the day time temps are OK.
I once changed a boat from outboard engine to inboard. That involved a lot of glassing, mostly internal, but all done with west. It was in January and at times freezing. The epoxy all cured well - eventually.
 
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