cold weather epoxy question

Buckeyedude

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I'm looking at using a 4-1 epoxy to seal my transom. Us composite recommends using the 4-1 over the 2-1 or 3-1 in colder temps. I know that warmer is better, and colder increases cure time, but how cold is too cold? Does anyone have any experience using epoxy during the colder months? Thanks
 

Auger01

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Re: cold weather epoxy question

I'm looking at using a 4-1 epoxy to seal my transom. Us composite recommends using the 4-1 over the 2-1 or 3-1 in colder temps. I know that warmer is better, and colder increases cure time, but how cold is too cold? Does anyone have any experience using epoxy during the colder months? Thanks


Most expoy will specify a minium tempature required for complete cure. West system specifies 60 degrees for the slow hardner and 35 for the fast hardner. For big layups I still use the slow hardner in the winter to allow for longer working time. Keep in mind that if you buy the epoxy intended for cold temps, it will be virtually unusuale in the warmer months ahead.

US comp. should have all the information about minimum temps for each of the epoxies that they sell.
 

a1964rn

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Re: cold weather epoxy question

From US Composites Epoxy FAQ:
"The 4:1 Fast hardener is also an excellent hardener. You can use this hardener down to 45 degrees. Caution should be taken when working with large batches."

faq_epoxy2
 

Woodonglass

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Re: cold weather epoxy question

Unless you HAVE experience, I'd recommend NOT using the 4-1. It can/will "Flash" off on you very quickly if you make to big of a batch. Even if the temps are 45?. When it goes...It GOES! You could end up Wasting a lot of expensive resin. I'd stay with the 3-1 and Wait for temps of 60? or higher. JMHO
 

a1964rn

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Re: cold weather epoxy question

The pot life of the 4:1 is 15 min. at 80 degrees. This time increases as the temp drops. Just have your transom ready, mix up a batch, pour it on, and roll it on. After it's poured on the transom, you'll have plenty of time to roll it.
I used the 3:1 epoxy. I kept a brooder lamp on it and let it cure overnight. You can use a heater to keep it warm. Epoxy fumes are not flammable, so a heater blowing on it will work fine. Use a heat gun to warm up the transom prior to applying the epoxy will help as well.
 

bradleymc

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Re: cold weather epoxy question

I have tried regular Epoxy in the winter and it did not cure properly. I used US composite 4:1 three days ago to seal my new deck. The temperature here in NY has been about 40-45 during the day and about 30 degrees at night. It's been about 72 hours since I applied and I'm not seeing any issues. I would rather have waited for warm weather but striper season isn't too far away for me. If you're using it on a transom, and it's possible to wait for warmer weather, I would wait. If you end up using the 4:1 I would suggest making sure it is warm before you mix it (in other words don't store it in the garage if it's 40 degrees).
 

Yacht Dr.

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Re: cold weather epoxy question

I'm looking at using a 4-1 epoxy to seal my transom. Us composite recommends using the 4-1 over the 2-1 or 3-1 in colder temps.

What do you mean by "seal the transom" ?

Sometimes its best just to pick a day thats warm enough.

I mean .. you can preheat the substrate .. and apply .. and have variables .. .. but is it worth an hour job in the correct heat/temp rate VS. heat guns and 4hrs of babysitting this job ?

What are you trying to do ?

YD.
 

Buckeyedude

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Re: cold weather epoxy question

Thanks for input.
YD, Im in the middle of a restore and need to pull my old transom and make a new one. The epoxy is for sealing the arauco plywood.
 

Yacht Dr.

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Re: cold weather epoxy question

I wouild say buy your time at this point .. Its close that the weather will break for a few days.

Get all your stuff ready to go for that Perfect day and then Go for it.

Unless your some die hard that has to have your cake baked NOW ..

It will save you alot of hassle IMO doing things when things are done when they should be done ..

Try to rush it to the next step might bring you back two steps ..

YD.
 

Woodonglass

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Re: cold weather epoxy question

Well then, You have several options for your transom wood. Epoxy is one, Poly and CSM another, Marine Varnish and Paint another, Marine varnish only. Lots of choices. Depending on how you Store and care for your boat should dictate the method you use. If she's covered and out of the weather then I'd just varnish it and be done with it. If you don't want the look of natural wood then put 2-3 coats of Rustoleum or any other good quality Oil/Alkyd based paint on it and if you always predrill and coat any fasteners with 5 min epoxy, that ole' transom will last for decades. But hey, I'm just an..
OldDumbOkie.jpg
so what do I know!!!!;)
 

jigngrub

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Re: cold weather epoxy question

4:1 and you're good to go bucky, you have a small area to cover and will be mixing small batches.

The warmer you keep the work area the less time between coats.
 

pauloman

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Re: cold weather epoxy question

use Basic No Blush marine epoxy with winter cure in temps 35-45 or so, Use Basic No blush regular cure for temps from about 50-80 and use their summer cure for temps over about 80 degrees

paul
 

Yacht Dr.

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Re: cold weather epoxy question

Preheat Everything before you start when your working in cold weather ..

Not too much but try to get everything the same temp.

It works much better. :) ..

YD.
 

Buckeyedude

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Re: cold weather epoxy question

Thanks, it got 64 here today! Wish I had everything ready prior to this:facepalm:
 

Buckeyedude

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Re: cold weather epoxy question

ordered 3-1 epoxy yesterday, i will just make sure it is warm when i try to make it happen!
 

F14CRAZY

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Re: cold weather epoxy question

I emailed US composites a while back about the same thing:

Phillip,

Do not attempt to use 3-1 hardener below 55 degrees F. Our 4-1 fast hardener will cure as low as 45 degrees F. Nothing works below that.



Thank you,



Steve
 

ctswf

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Aug 7, 2012
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Re: cold weather epoxy question

hi guys, im about to coat a new transom also, how bad are the fumes? Is it out of the question to do the work indoors in your basement? Or will I get high over night in my sleep
 

F14CRAZY

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Re: cold weather epoxy question

Epoxy: no problem. Polyester: baaaaad fumes
 
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