Epoxy problem

BlueLancer

BlueLancer

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I bought 5ltr of epoxy resin and hardner for use on the boat. It will not go off. no heat generated when resin and hardener mixed together. I assume its because I have stupidly allowed it to live in my works shop at below 18c. I have now placed it in my boiler room to warm through , will it now work, or have I made a very expensive error?
 
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The instructions for West say it can get cold (can't remember exactly how cold, but certainly less than 5º) without any problem as long as it's rewarmed again before use.

Pete
 
Unlikely to be down to the temp. It would cure eventually. Too little hardener and it will cure eventually. Too much hardener and it may never cure.
 
I would suggest purchasing a set of digital scales and mix by weight. Pumps are a bit inaccurate. I have a jewellers set that measures up to about 200 grams and a kitchen set for up to 5 kilos. Sometimes you may only want a teaspoon full of mixed epoxy. The most expensive of the scales was $7. Very easy to get the perfect ratio.
 
It important to get the proportions of resin and hardener correct with epoxy as it cures by reaction between the two as opposed to polyester where the hardener is only a catalyst.
 
I was doing some glassing in the boat yard and a bloke walks up says "I used epoxy on me boat on Thursday and it's still not set, any ideas"

I asked him what method did he use to mix the epoxy and hardener, he replied "well I used the pumps because it's to expensive to get it wrong".

Then he continued, "it has to be mixed at 5 to 1 so that what I used".

I asked if that is what he did, you may have guessed by now what the problem was.

He was mixing 5 pump strokes of resin to one stroke of hardener.:eek:

It actually took me some time to convince him that a single stroke on each pump was one small batch.:)
 
oldsaltoz said:
He was mixing 5 pump strokes of resin to one stroke of hardener.:eek:
Click to expand...

Some brands that's correct, as they use the same sized pumps. Others, as you know, it's one stroke each with different sized pumps. That's why I asked the OP what make of epoxy he's using.

Pete
 
oldsaltoz said:
I was doing some glassing in the boat yard and a bloke walks up says "I used epoxy on me boat on Thursday and it's still not set, any ideas"

I asked him what method did he use to mix the epoxy and hardener, he replied "well I used the pumps because it's to expensive to get it wrong".

Then he continued, "it has to be mixed at 5 to 1 so that what I used".

I asked if that is what he did, you may have guessed by now what the problem was.

He was mixing 5 pump strokes of resin to one stroke of hardener.:eek:

It actually took me some time to convince him that a single stroke on each pump was one small batch.:)
Click to expand...

many years ago, this was my mistake when first using the International epoxy system. four pumps on the resin and one on the hardener. Should have been one pump of each (pumps differnet sizes). Made a right mess of the job. I use calibrated syringes instead now.
 
I use good old measuring.
I mix in the bottom of a milk container and use a big lolly stick (spatula) I mark the resin and hardener levels on the stick (2:1 for mine) and just fill to each level, then stir.
Works fine.
I've left mine in the cold many times. You do need to warm it right through (gently for a day) before mixing though.
 
I only use FGI, its 5:1. Place small plastic container on scales, zero it, pour resin to amount needed. Add 1/5 the weight in hardener and mix. No syringes or pumps to clog up and perfect all the time. Small mental calculation required only.
 
Fortunately I had no such problems with the Epoxy Mastic I use.
(from rust.co.uk).
The boat is steel and this stuff is an epoxy with much filler in it.
Its brushable, retains some flxibility and doesn't flow out (its designed not to as its meant to maintain its thickness on corners and edges.) and is easy to sand.

I used it down to 5c mixed 'about' 1:1 using a measuring spoon - I didn't measure it very precisely after the first batch set okay.
I'd recommend it to any steel boat owner.

The unpainted test areas of it exposed to the elements for 12months are still intact.
I
 
I had no problem getting my epoxy to go off recently. My 1st time use of 2 part epoxy - was supplied in 2 tins - 1 was 5L tin with 3.75Ltr base and the 2nd tin 1.25 ltr hardner - mixing ration was 3:1 so simply poured hardner into base and mixed

1st roller tray fine
2nd roller tray - mix had a bit of skin - another stir and was fine
went back for the 3rd roller tray -and the ruddy tin was smoking.. too hot to touch and the contents rock hard!

I freely admit that I can sometimes be a complete muppet and have now learnt my lesson!!
 
Thanks for the various replies. To answer the questions:

1. Its the West System.bought from East Coast Fibreglass Suppllies

2. I bought the pumps from them,so I can only assume they are the correct ones, said so on the packet.

3. I have read the distructions till I am blue in the face. Note I will read again.

4. Ratio is quoted as 5 parts resin to 1 part hardener.
 
I've just used some very old West epoxy and 205 hardner, it worked fine.
There were some crytals formed in the epoxy container due to the long storage.
I followed Wests instructions and immersed the container in hot water. The crystals soon dissolved.
I actually mixed by volume after calculating the values from the quoted specific gravities ( more like 4.5 to 1 ) Using a small marked glass to measure the hardner.
You will be able to tell by inspection that your quantities are roughly right ( gross error check) and those pumps are quite reliable.
Have you just made up one batch as yet? you could always test another small amount.
Mine got to the 'tacky' stage in 2.5 hours at 18 C and was rock hard after 5 hours.
Which hardner are you using?
 
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I have maltreated epoxy in every possible way, including letting it get below freezing.
It still has always worked after warming.

My bet is on wrong mix as suggested by others. The pumps already dividing by five and then you dividing by five again, getting 25 to one not 5 to 1.
 
You didn't say what quantity you'd mixed, and how or if you had applied it.

I do know that some epoxies won't cure near some other chemicals. Pledge for instance. Glued some laminations together around a wooden jig (coated with Pledge as release agent) and it turned into a sugary mush.

Mixing a small quantity on a magazine cover, same thing.

Dunno if that helps, but worth bearing in mind.
 
BlueLancer said:
1. Its the West System.bought from East Coast Fibreglass Suppllies
2. I bought the pumps from them,so I can only assume they are the correct ones, said so on the packet.
Click to expand...

And just to confirm, you are using equal numbers of pump strokes, ie one of resin and one of hardener? Apologies if that's egg-sucking, but your answers so far don't make it clear.

Pete
 
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