Storing West System Epoxy

[JayStPeter]

On a recent project I used West System epoxy. Now I have 3 cans with the dispensing pumps installed. Can I store it that way (probably for months between uses) or do I need to remove the pumps and put the caps on?

[Wade Lippman]

I've had it that way for about 3 years now. I use a ounce or two every now and then, and it works just fine; if a bit darkly.

[Dell Littlefield]

I agree it can be stored with the pumps installed. Just be aware that the catalyst will darken with age. I learned that the hard way halfway through a canoe build.

[Mike Malott]

I've had an open can with pump since '04 and it remains fine.

Mike

[JayStPeter]

Thanks, that answers that. I guess I'll have to deal with the darkening when it happens. Good to know that a trip to the local marine supply store might be necessary if I need it clear.

Jay

[Ted Jay]

Thanks, that answers that. I guess I'll have to deal with the darkening when it happens. Good to know that a trip to the local marine supply store might be necessary if I need it clear.

Jay

This is what the website has on storage/shelf life:

Shelf life

If the containers are kept sealed when not in use WEST SYSTEM resins and hardeners should remain usable for many years. Over time, 105 Resin will thicken slightly and will therefore require extra care when mixing. Hardeners may darken with age, but physical properties are not affected by color. Mini Pumps may be left in containers during storage. It is a good idea, after a long storage to verify the metering accuracy of the pumps and mix a test batch to assure proper curing before applying epoxy to your project.

[Cliff Rohrabacher]

Refrigerate it and you'll keep it longer.

The stuff has a long shelf life but it's not for ever.
You'll see it going bad slowly It won't change overnight.