Epoxy hints for hot weather?

[riverron]

I was doing some clear coats with unthickened epoxy last weekend and the temperature in my garage was around 80 with fans. The epoxy looked to cure very quickly and caused a mess. I wound up having to sand some of it.

I am using MAS epoxy and the cure tables they provide say somewhere between 17 to 23 minutes for pot life in the 77-87 temp range, but it seemed much faster.

1) I have read use smaller batches, but I didn't think mine was very large. I use the big red cups and it was barely 1/4 full.

2) I also read pour into a shallow dish. Anyone doing this and what did you use?

3) portable air conditioner? Anyone using these? Recommend models?

4) move to Maine ?

Any hints for using epoxy in warmer temps would be appreciated.


Thanks

[chaertl]

Work fast. Just kidding. Try keeping the epoxy cool by putting the mixing cup in a shallow tray of ice water when you're not holding it.

Chris

[craig]

Your epoxy should be in the cup only as long as it takes to mix. After that, pour as much as you can onto the surface you are coating and do a quick-and-dirty initial spread. Go back later to smooth it out. Spreading the epoxy over a large surface will lower the temperature and prevent the exothermic reaction from increasing the temperature. I used the medium hardener and was able to work in 90-100 degree heat with no issues in my garage in Nashville (no air conditioning). The great thing about high temperatures is that the epoxy cures so fast! You can work very efficiently by wetting out the epoxy and doing all fill coats in one day (separating your coats by just a few hours). I was using a blushing epoxy, so this paid double dividends for me because I didn't have to wash away any amine blush between coats. Finally, the epoxy is stronger when applied to a not-fully-cured undercoat.

[Shudoman]

Are you using the slow hardener? I don't think you mentioned it.

I built the PocketShip in FL and I don't think my un-aircondition garage was ever below 80. Using the techniques already discussed in this post I was able to deal with it. However, I can't say it was never a problem. I did suspend or put off some of my epoxy work until 2am just so I wasn't sweating into the stir pot.

Anyway if you don't have the slow hardener I would recommend getting enough of it to get you through the summer.

Bill

[riverron]

Thanks for the hints and I am using slow hardener. Sounds like I just need to get my process figured out/adjusted. Just another learning opportunity.

Additional information, I was doing clear coats on the small floor supports 3,4,5 and 6, so I really couldn't pour epoxy on them too good. I was holding the cup in my hand and brushing it on both sides. So I think it just heated up in my hands. Pot life at 80 degrees is pretty short. I think I will try Chris's suggestion on putting the cup in ice water and just doing 1 side and mixing smaller batches.

Craig, I will/have been following your suggestion on the larger pieces. I am getting ready to do the large 16' side panels with fiber glass.

thanks as always for the expertise!

[riverron]

I tried the suggestions and everything turned out fine this time! I used a bucket with ice to hold the cup of epoxy and I also poured the clear epoxy on the boards and used a roller to spread it out. It didn't thicken up this time and it was about the same temperature. Thanks for the help!