Epoxy issue

[Riverjohn]

Hello,
I have an issue with the epoxy not setting up. I used West Coast 207 Epoxy and Hardner. A few weeks ago I successfully Applied the outer Fiberglass and epoxy to the Canoe I am building. after fairing the inside and prepping the canoe I applied the glass and epoxy to the inside and followed the instructions as before mixing it the same. It's been a week and the epoxy is still very tacky to the touch and appears not to be getting hard. a lot of bubbles keep appearing and it looks as if the fiberglass is lifting up to the surface. what are my options at this point? i am thinking of removing the fiberglass and using acetone to remove the epoxy so I can start over. anyone got any advice? The temperature inside the shop was 68* when I started and 74* when i finished the second coat. makes no sense to me as why the outer setup but the inside didn't. any commits would be greatly appreciated.

[Cruiser]

One suggestion, although it won't fix this issue, but does add some assurance going forward. Save the containers you mix the epoxy in each time, check them in the morning to make sure the epoxy has set hard. It's a ritual for me now, when I use epoxy, I set the containers aside (there is always a little left ) and check in the morning that they set hard ... let's me know all went well.

If the epoxy hasn't setup right, then you really have little choice but to pull it all off and start over. I wouldn't use acetone or any solvents, as soon as you apply they start to dissolve the bad epoxy and carry it deep into the wood ... that is something you want to avoid. Instead consider modifying a couple of paint scrapers and scrape the interior again to get rid of most of the residual epoxy, then you can lightly resand to prep.

I reshaped a couple of old paint scrapers to do the interior, they look like this, needed to b sharpened often, but they did work well



The two main reasons epoxy doesn't setup is 1) improper mixing 2) improper ratios used ...... as a builder either one is easy to accomplish, we all try and do it perfect every time, but sometimes it gets messed up.

My last build blog was done in detail just to use for reference purposes and starting at post#97, at this link, I discuss epoxy issues and some simple things to do to prevent setting issues.

https://www.canoetripping.net/threads/l ... 054/page-5

Pulling epoxy back off is a lot of work and mess, it is worth a few steps to ensure success ..... although I use pumps for epoxy, I also weigh for any larger jobs, such as a canoe glass job .... pumps are prone to delivery issues through "burps" and user error, the weight gives a final check.

I wish you good luck with the correction, don't get discouraged, just take your time to get the removal done well. I would also do a single batch of epoxy to double check it is good. Also, make up a process that works for you, to make sure you mix the epoxy thoroughly, whether that is a timer, number of stirs, whatever keeps you mixing for the few minutes it takes.


Brian

[Stephen]

Brian

My last build blog was done in detail just to use for reference purposes and starting at post#97, at this link

I thought I'd share a trick I learned just in the last year or so. If you click on the number #97 in your post, or on the date of the post, the post will jump to the top of the browser window, and more importantly, the browser address/ search bar will now contain a URL that points to that specific post in the thread. https://www.canoetripping.net/threads/ ... ost-107377

This trick seems to work in a lot of the forums I visit. The Wooden Canoe Heritage Association forum uses the same method if you click on the date. If you click on the little post number it opens a window with a permalink to the post, but does not jump that post to the top of the page. In the Bear Mountain forum you either click on the blue title of the post, or on the tiny grey box to the left of the poster's name just below the title.

Stephen

[Cruiser]

Thanks Stephen, that is a very useful tip


Brian

[Stephen]

I'm glad you liked it.

I've been poking around some more on canoetripping.net and found out there's an even easier way than what I said before. Hover but don't click over the share symbol to the left of #97 to bring up the "Share this post" window, then click the symbol to the left of the URL to copy it directly to the clipboard. Easy peasy.

There are also options to share to Facebook, Twitter etc. if you're so inclined. I always thought the little share symbol applied to social media only; I didn't realize it also had the copy to clipboard feature. Live and learn I guess.

Stephen

[Cruiser]

I looked and you are right, the board just migrated to this software, my understanding is that it is a lot more up to date than the previous version .... so those sorts of functions make sense ... thanks again

[Traveler]

Riverjohn, just a shot in the dark, but was the temperature maintained at 74 degrees or so for at least a day or two after you applied the interior epoxy? If not, then before stripping the inside stuff off it might be worthwhile to apply a good long period of elevated warmth, if you haven’t done this already - maybe invert your canoe onto a couple of saw horses and get one of those cheap little 120 volt heaters underneath for at least a day. The inverted canoe will trap a lot of the heat, which would greatly accelerate the curing if that was the problem. Just a thought …

[Jim Dodd]

I agree with Cruiser.

Mix ratio, could be off. Did you use pumps ? Or improper mixing, basically not long enough. Betting the mix ratio is the problem.

The Fix ? If you can pull the cloth ? I'd pull it. Scrape as much of the resin out as possible. Hit it with Acetone ( Wear a Filtered mask, made to be used around varnish ). 3M makes a reasonable priced one. Use it !

After a Acetone wash, wait a week, and check for any tack to the inside.

I helped a guy that failed to mix the resin very long on his seal coat. Acetone and a good sanding had him back in business .

Good luck, and share your results !

Jim

[Riverjohn]

Thanks for all the helpful info on this from you guys! just to give an update and answer some of the thoughts and questions you guys had, yes the temp. in the shop was maintained from around 70* to 85* before and after applying the epoxy for a couple of days. after about 6 days I carried the canoe outside and set it in the sun (on sawhorses) for the afternoon. it became more tacky to the touch. I left it out overnight as the temp only got down in the 50's.The next morning it appeared to stiffen up but when the sun warmed it up it went right back to being Tacky. I carried it back inside the shop and hadn't touched it other than to feel the inside now and then for the past few days. Still tacky but just a little firmer in a couple of places but again I set it outside and it went right back to the tacky feel. Today after letting it set outside (temp was 66*) it was just as tacky so with nothing to loose i started to peel the fiberglass off. I was able to remove every bit of it with some pulling and prying. It did not pull any of the wood off with the glass which tells me it never bonded to the wood. pulling it off was like pulling peel ply off. i do have a lot of sticky resin left on the inside. it was a relief getting the glass off as i had not been looking forward to removing it, I thought I was going to have to use a butt load of sanding disks and make a scraper like Cruiser told about to get it off.
I am in agreement with you guys about the mixing issue. I used pumps to mix. I had my helper mix up some just as he had did when we glassed the inside, the next day it was still loose in the cup. this reaffirmed that the mixture was incorrect when applied. I will make sure when the time comes to re glass the inside the mixture it correct! only issue I have left to resolve is getting the inside ready to re apply the glass, I think removing the sticky epoxy is going to take a few days. not sure on the best way to get it off.
This is my first canoe, I cut the Cedar trees 2 years ago here on the farm, sawed them up and waited till the wood dried enough to get started. It's been an enjoyable project so far with very few setbacks. Just got to get on to trimming it out, as spring is near and the river is calling.
Thanks once again,
John

[Cruiser]

Good luck in your re work, please consider posting a few pics and let us know how you are getting on with the build ... for those of us between builds, it is nice to see a build in progress



Brian

[Traveler]

Great news that you were able to get the cloth off so easily. You are definitely back in business without it turning into a major pain. Jim’s point about scraping the remaining sticky epoxy as much as possible followed by acetone sounds like solid advice (don’t use a petroleum product like paint thinner or turpentine etc., since it will leave residues in the wood that could mess up your second shot at the inside coat). All the best with it, and updates appreciated.