Does damp and rainy weather effect hardening time for resin?

I have noticed that during damp and rainy weather, the hardening time for my resin takes much longer than a day when it is dry (using the same amount of catylast, resin and same temp. Does this seem right, or am I screwing up?

thats right - part of the resin curing process is the styrene evaporation. If the humidity is high (misty or rainy), the air is saturated so evaporating is more difficult. Sometimes if it is really hunid, it takes forever for even a really hot batch to go completely off.

Agree, here in the east, resin setting outdoors (under cover) in humid or rainy weather or late evening/overnight summer are almost impossible. I almost always end up bringing the board inside overnight to set up.

A good alternative to dealing with humidity, temperature or simple impatience is to look into the UV catalyst which can be used in any clear polyester surfboard resin. I was constantly having to deal with temperature swings of 20+ degrees where I live plus the high humidity. It would seem that elimination of MEK catalyst in the lamination process alone might outweigh all reasons to look for a change. Check out www.surfsource.net for more info on the powdered UV catalyst- SunCure. (Swaylock’s archive have lots of info on this topic) Tom S.

Howdy Tom ol Buddy.I am now of the opinion that Suncure is the only way to go no matter what the weather looks like.Glosses suck though.Any luck on this?? R.B.

Cleanlines… I’ve been mixing a fair amount of styrene, surfacing agent and a little catalyst, running it through a filter cone, brushing it on, letting it set awhile and taking it outside. Still need to wet/dry and buff but seems OK. In fact, I’ve had fewer problems with rail run off and drips.

Roger: I gave up on the finish coats with UV cure. I suppose it can be done, but after walking outside to flash cure it and have a wind gust blow fresh tree bloom pollen or other crap all over my gloss I got discouraged. When I was using a lot of the UV resin I did my lamintions with it then follwed with a MEK cured hotcoat and gloss coat. Hey I talked to Bill last night and exchanged e-mails with Matt too. Give you a call today sometime. You got DSL?? Tom S.

Howzit Mr. Clean, After using UV for the last 3 years I’m also a big fan. But when it comes to hot coats and glosses, catalyst is the only way to go. Aloha, Kokua

Thats what I figured,I tried it every whichaway and came to the same conclusions.My friend Harry Balzac likes to kick the hotcoats (after the wax rises)in the sun and they look fine.They are harder to sand because the hotcoat is 100% cured.I like that two day window of semi cured resin for sanding and polishing.Am I lazy or smart?Beats me.Tom I just got my computer fired up today on DSL…been on a borrowed one for six months.Later. R.B.

Howzit Mr. Clean, My vote says smart since I too like to sand when it’s still a little soft. Aloha, Kokua