epoxy problem

Welcome to the new Bear Mountain Builders Forum - an interactive internet service we provide to encourage communication between canoe and kayak builders
Post Reply
podunk
Posts: 36
Joined: Mon Jan 26, 2009 6:04 pm
Location: indiana

epoxy problem

Post by podunk »

Does epoxy go bad with age? Recently made a paddle and a portage yoke and covered both with US Composites 635 thin. I glassed one side of the paddle blade for strength and coated the entire yoke. Problem is the yoke got gooey and won't set up. Did both at the same time, in the garage (heated temporarily), left sit overnight. brought both in the house for 7-10 days. Problem was when I took them back into the cold garage, yoke clouded up and got gooey and still is 2 weeks later. Both were covered from the same mix of epoxy so I don't think it was improperly mixed. Epoxy is almost 2 years old but is stored in the house. Is there a shelf life for epoxy?
User avatar
Patricks Dad
Posts: 1476
Joined: Wed Oct 13, 2004 1:11 pm
Location: Warrenville, Illinois

Post by Patricks Dad »

I'm not familar with that brand of epoxy but in general, the shelf life is very very long. Hardner will typically turn yellow or redish with age but otherwise still useable. If only the yoke "went bad" but not the paddle, I doubt it is a shelf-life problem (they both were done at the same time with the same batch, right?).

I don't have experience with cloudy epoxy but to try to get rid of the gooey aspect, I'd experiment with heating it with a hair dryer or some other source of (nearly) excessive heat to see if that works. I doubt it will cure the cloudiness. In the end, I'd guess you will need to sand the yoke down and recoat. Leave the yoke in a warm environment for the entire time the epoxy should take to cure.

Sorry I'm not much help. Good luck!
Randy Pfeifer
(847) 341-0618
Randy.Pfeifer1@gmail.com
podunk
Posts: 36
Joined: Mon Jan 26, 2009 6:04 pm
Location: indiana

Post by podunk »

It didn't really turn cloudy, just gooey and wet, still hasn't set up, yet it wasn't like that til I took it back into the cold weather. Very strange. The hardener was a yellowish color when new and has been stored in the house. Haven't had any previous problems with this epoxy. I used the same kit on my canoe but I'm kinda leary of using it on anything else. Oh well.
willo
Posts: 156
Joined: Sun Jul 15, 2007 12:48 pm
Location: Echo Bay ON.

Post by willo »

Did you wipe down the yoke with something different then the paddle? If the epoxy was the same for both there must be something else that has interfered with the hardening.
sedges
Posts: 325
Joined: Fri Jul 09, 2004 5:37 pm
Location: georgia

focus on the yoke

Post by sedges »

If both items were coated with the epoxy from one mix and one set up fine and the other didn't the problem is with the yoke. What kind of wood is it? Has it ever been coated with anything before like sanding sealer or oil? Was anything added to the mix before the yoke was coated like a thickener?

I've used epoxy much older than that with fine results. It sometimes gets discolored. The hardener will turn purple over time, but it still cured. I use old stuff for gluing up laminated stems and other things that are never seen.
podunk
Posts: 36
Joined: Mon Jan 26, 2009 6:04 pm
Location: indiana

Post by podunk »

The yoke had been epoxied before but it was sanded down . There was some color left in the wood from the first coat but I believe most of the first coat had been removed. The yoke is cherry. My concern is using this epoxy on my decks and gunwales which are installed but haven't been coated with anything yet.
CatFaber
Posts: 20
Joined: Wed Nov 03, 2010 4:55 pm

Post by CatFaber »

When I made my second canoe I used epoxy left over from my first, built four years previously. The hardener had turned a bit yellow, which slightly affected the final color of the cured epoxy, but aside from that it worked fine.

I did once have a batch of epoxy fail in the manner you describe--it never set up. It was epoxy I bought from the hardware store to do a couple of small gluing jobs--"five minute epoxy." In that case the epoxy came in one of those double syringes--I had broken off the detachable double cap, mixed a little of the epoxy, and put the cap back on, only I put it on backwards by mistake, mixing a little epoxy in the hardener and a little hardener in the epoxy.

The *second* glue job I did with it I had to cut some of the nozzle off to get rid of the hardened epoxy. I made the mistake of using the rest, which seemed okay, and *that* was the stuff that never set up properly.

Is it at all possible that something similar adulterated your hardener or epoxy?

I have also heard of epoxy not working on certain woods--oak is supposed to be notorious for this--but I never heard of anyone having trouble with cherry.
User avatar
Glen Smith
Posts: 3719
Joined: Sat May 08, 2004 9:08 am
Location: Baie-St-Paul, Quebec, Canada

Post by Glen Smith »

To repeat Willo's question: did you wipe the items with anything before applying epoxy? Anything at all?
Are you certain the mix ratio is correct and it was well stirred?

If the items are placed in a cold/humid place before the epoxy has set, it can absorb moisture and become cloudy.

I have never worked with that brand of epoxy but some epoxy products can produce "amine blush" on the surface as it hardens. This makes it feel gooey, oily or waxy. It can be removed by wiping with a cloth and warm water. Do not use anything but water to remove amine blush. Wipe dry with paper towels. Set aside for a day or two and see if the surface is dry and hard. If yes, the problem was blush.

If still sticky, scrape off, sand, clean and apply epoxy again after testing it on a smaller piece of scrap. Respect all use and application conditions outlined by the manufacturer.
Post Reply