Can I use poly resin when it's cold out?

[tmh]

I'm replacing my boat floor and will be coating it with poly resin (yeah, i know epoxy is better, but I HAVE a lot of poly resin so i'm going to use it). I had researched Epoxy Resin and it seems there are different formulas for warm and cool (nothing for cold as best I saw). Is it the same for poly resin?

I just saw a different thread where someone recommended a tarp with a heater when doing various work, but it wasn't specific to poly resin. Also, I'm not going to do this work now when it's 30 and below out, but when spring peaks out here by Lake Ontario I'd like to get started - maybe 45-55 deg. Is THAT OK for working with poly resin?

Also, what should I use as filler to make a more putty like resin for certain parts of the job?

What would I use to make a thinner resin if I want it to penetrate a bit more?

Thanks.

 

[croSSed]

Re: Can I use poly resin when it's cold out?

Yes, you can work with poly when its colder. 55 would be okay I think, but 45 is getting down there. Store your resin inside where it's warm so that at least you start with room temperature resin. Same with the catalyst. If you can somehow heat the parts you are working on, that would help. For instance, if you are going to be glassing a floor section, bring it inside until you glass it.

Also, mix the MEKP catalyst at about twice the ratio as you would if you were working with it at room temperature, i.e., if the directions for your resin say mix at a ratio of 1% catalyst, mix it at 2%.

As for thickening, it depends on what you are going to use the thickened resin for. I've found using micropheres to work really well. If I want the bond strength to be higher I mix in some milled fibers. I've been making my own by cutting up by hand left over remnants of cloth I have laying around. 1.5 oz. mat works well for this.

I don't think you'll need to worry about thinning the resin. It will penetrate fine. If you're worried about it penetrating an area, just give it 2 or three coats. Wait about an hour between coats and you should be good.

TG

 

[klos]

Re: Can I use poly resin when it's cold out?

I don't like to let it get below 60 in my shop when working with polyester. But I guess 55 would not be that much different. Just catalize a little more.
resin is still curing for quite a long time after it is hard. At lower temps I would post cure with halogen lamps (after the resin has hardened for a couple of hours).
Home depot has nice 500w halogen lamps for $14 right now.
Put a thermometer in front of what ever you are trying to post cure, don't let it get over 75deg or so.

 

[tmh]

Re: Can I use poly resin when it's cold out?

OK, thanks. One more question:

When I mix up a batch of resin/catalyst, about how long can I work with that batch? I guess I'd want to "group" parts of a job so i can hit as much with each "batch" as i can before it starts to harden, right?

I may try the halogen lamp idea. A safe way to heat a bit, i assume.

 

[Chris1956]

Re: Can I use poly resin when it's cold out?

tmh, The "pot life" of the resin is mainly based upon temperature, and the amount of cataylst you have added. If you catalyse for 70 degrees and are working at 50 degrees, you will have a long pot life.

I have found that if you catalyse for a 70 degree day (on a 70 degree day) and do not let the sun's warmth get to the resin, it will last at least 15 min. In the current cold weather, the resin may not get more than firm and sticky, without some heat.

 

[Frank Acampora]

Re: Can I use poly resin when it's cold out?

There is no set time--It's an exothermic reaction (generates heat) so the bigger the batch the faster it cures in the pot. And of course, the more catalyst the less open time. You need to experiment.

BTW, there are different resins made for different open times.

 

[klos]

Re: Can I use poly resin when it's cold out?

Once it start to "kick", when you start to see it gel up or get lumpy, it's no good. Throw it out and immediately clean with acetone anything you don't want encased in plastic.

 

[Saskatoon2005]

Re: Can I use poly resin when it's cold out?

.....then you will have to mix up a brand new batch... and if this happens make sure you remember what amounts you mixed and how long it was useable. Then make appropriate adjustments for future batches.

 

[croSSed]

Re: Can I use poly resin when it's cold out?

What I do is I get all my cloth and other materials ready that I'm going to use in a section. Have the cloth all laid out like it will go when I apply resin; have all my tools and other equipment right there. Then I mix a batch of resin. Unless the job is really small, I mix a pint. If it is really small I mix a cup. Then start slopping it on there. Running out of resin is better than having to throw resin out 'cause it's expensive. Once you run out and you see how much further you have to go to finish that part of the project, you'll know how much more resin to brew up. You have to move quickly to get the next batch ready though so the previously applied resin doesn't completely harden, and you ruin your paint brush (if you are using one). BTW, I've discovered that to do one side of a 4' floor section using one sheet of 1.5 oz mat takes at least a quart of resin.

TG

 

[Saskatoon2005]

Re: Can I use poly resin when it's cold out?

Useful information,

I will be doing my boat in the spring and all this inforamtion I will keep in my notes to know when I do it to my boat. Thanks for the key notes....LOL!

 

[iwombat]

Re: Can I use poly resin when it's cold out?

At 50-degrees you may never get poly to kick properly. Poly cures in the absence of air. Kicking brings the wax to the surface to provide a barrier. If you can't get it to kick properly, you can cover it with a variety of barriers from release agent to saran wrap, and it will cure properly.

Adding more catalyst works to a point, but anything less than 60-degrees is pretty problematic no matter how much you add. Heating the mix in the pot before applying can help, as can heat lamps. Best of luck.

 

[croSSed]

Re: Can I use poly resin when it's cold out?

At 50-degrees you may never get poly to kick properly. Poly cures in the absence of air. Kicking brings the wax to the surface to provide a barrier. If you can't get it to kick properly, you can cover it with a variety of barriers from release agent to saran wrap, and it will cure properly.

Adding more catalyst works to a point, but anything less than 60-degrees is pretty problematic no matter how much you add. Heating the mix in the pot before applying can help, as can heat lamps. Best of luck.

I think it depends on the resin. The poly resin I'm currently using gives directions for adding 2% MEKP when it is 50-55 deg. Also, I don't use resin with a release agent (wax). Adds extra work (sanding) when I come back to the project the next day. Now I just wipe down with acetone and start applying new glass/resin.

TG

 

[iwombat]

Re: Can I use poly resin when it's cold out?

If you don't need to heat out the release agent you can work with colder temperatures for sure.

 

[Terrulle]

Re: Can I use poly resin when it's cold out?

A good way to get your catalyst level right is to use the following:
Ideal catalyst level should be 1.8% at 77degrees F. Increase ideal level .07 for each degree below 77degrees. 60degreesF should be the minimum temp used at a maximum catalyst level of 3%.
For instance: Temperature of resin is 70 degrees
7 X .07 = .49 + 1.8% = 2.3%

 

[Terrulle]

Re: Can I use poly resin when it's cold out?

I have used resin at 45-50degrees with no problems but I did try to bring everything up to temperature and keep some warmth on what I was doing until it set up.

 

[iwombat]

Re: Can I use poly resin when it's cold out?

I've had nothing but problems in that temp range. When it gets that cold, I just use epoxy and save myself the grief.

 

[Terrulle]

Re: Can I use poly resin when it's cold out?

I think that 55degrees should be the coolest that you should try to glass anything. Especially on anything big, such as transoms, floors etc. too much of a risk. That's a lot of $$$ if resin doesn't kick. It's not a big deal if it's a small repair. you can then focus on the one area and not be moving lights, heaters, etc...., all over the place.

 

[tmh]

Re: Can I use poly resin when it's cold out?

OK, looks like I'll wait for a warm spring day for the floor job. However, I want to make sure it only has to be warm for a while. If it's say in the 60s when I do the job during mid-day, then drops into the 40s at night (as it will in spring here) is that OK? I don't want to screw around wit heat lamps, etc. unless I need to.

 

[iwombat]

Re: Can I use poly resin when it's cold out?

While I've never used it, there's also UV cure polyester resin. UV light starts the kick process and from what I can tell it's not temp sensitive.

Just a thought.