Interzone (Epoxy)

[Hitch]

We do a job from time to time that gets sprayed in Interzone, (number escapes me)

Always onto bare steel.
Air temperature, not baked.
Now and then we seem to get a few issues. Sometimes the colour seems to go pale, i read on the data sheet that happens if it gets wet before its cured. So quite possible damp air causes that.

Other one seems to be the paint drying, touch dry, but not hardening off, even after a week.

Anyone know what the shelf life of previously opened tins of it tends to be?

Either that, or not being thorough enough with the mixing.?

On the couple of times i have used it, i havnt had a drying issue.

 

[Welderpaul]

2 part? Incorrect proportions?

 

[steveo3002]

check the tins are not old out of date stuff

 

[Hitch]

2 parts, yes.
4:1 mix, surely no one could mess that up?

Last one had been opened about 4 months, actual tin date, ill have a look, but i was thinking if they have been exposed to air then closed and left...?

 

[steveo3002]

id not expect it to be gone off after being open 4 months , but im saying it might be years out of date

 

[Hitch]

I doubt it, but will check the next tin, i believe the colour is special order, so made to order.

 

[Welderpaul]

Get the Interzone technical rep out? Let him take a bit back for testing.
Once your sure your doing your bit right of course...

We use Leighs paints for most stuff that is important, had a bad batch once, 25x 20L tins. Sorted within a flash. We get them to come out to site FOC to do DFT testing. (Dry Film Thickness)

Mixing by proportion could be a cause? If you have part tins have people been guessing the quantities rather than just a full tin of hardener tipped into a full tin of paint?

 

[Chipper]

Temperature? Used PPG epoxy and it wouldn't cure well without a serious cooking. Back to Lechler, better all round and less fussy.

 

[Hitch]

Had it the other day, temp must have been about 25degrees,
It gives drying times from about 5degs up from memory, so that shouldn't be a problem either.

The mixing of these things, does it need to be very accurate?
I always use a mixing stick (when I can find one), or old aluminium rule.

 

[Chipper]

Guess it varies with makes, but the Lechler doesn't seem too worried, I've done it by teaspoons for little bits. Any road up you'd think the margin of error would be well taken care of mixing a decent amount like a half litre. 25C sounds warm enough too, if the stuff was in that temps for long enough.

 

[steveo3002]

are you mixing it in a tub with straight sides ...tapered cup will ruin the mixture ratios , but tbh you can often be fairly slap dash and it still works