Polyurethane Glue Shelf Life

[Jerry Rhoads]

Hi All,
I have not had much experience with the polyurethane glues. I have a bottle that is well past it's use date. It has not been opened.
I assume that it is still good. Is this correct?

How long of a shelf life does it have after it has been opened?

Thanks in advance
Jerry

[Steve Vaughan]

I think you're gonna be alright...just as long as it hasn't foamed up.

[Jason Roehl]

I've successfully used bottles that have laid around for several years. I've even had to poke a few holes in a crust that had formed to get the usable glue out of the bottle. Whatever you do, don't follow the instructions on the bottle--don't wet the wood you are gluing. That will cause it to foam too much and lead to a weak joint because it's been pushed apart by the foam (or the glue is pushed out of the joint by the foaming action). Let the moisture in the wood and the ambient humidity be sufficient for curing. To see the difference, put a drop of water on a piece of paper, then a drop of glue on top of that. Put another drop of glue on a dry spot of the paper a couple inches away and let them sit overnight. Once they're hard, pop them off the paper and bend the two drops of hardened glue.

[Larry Browning]

My experience has been that it does not have a very long shelf life even unopened. I had a new unopened bottle get hard as a brick after less than a year. I try to avoid the stuff unless I have a specific application that requires it. I have used it to glue pvc pipe to wood in making a DC blast gate and it worked well for that. Also, I would wait to buy it until I was going to use it and only buy in small quantities, just enough for the project.

[Bill White]

I'm with Larry. Just threw away an unopened bottle this week. Oh well....another contribution to the land fill.
Bill

[Brian Brown]

I keep hearing people say 1 year, but I get about 2. I think it depends on the humidity level where you are. I live in the desert.

[Eric Gourieux]

If the bottle is unopened and not hard as a rock, you should be ok. After opening, it usually gets hard and unusable within a few months. My current bottle suggests storing it upside down and squeezing excess air out of the bottle for storage. We'll see if that helps. I think the bottom line, in my experience, is that if it is not hard and flows ok out of the spout, it should be ok.

[Larry Browning]

I still say the best advice is to purchase just enough to do your current project right at the time you are going to use it, then throw the remainder away. Of course, I would also look for an alternative glue before using the stuff in the 1st place:rolleyes:

[Clint Baxter]

If the glue gets stiff, you can loosen it up by heating it prior to using it. I use the microwave for a short bit and it flows even better than new glue. I tend to only use it when gluing PVC or some type of dissimilar materials. Fine woodworking did a review, and in their report, this is where the polyurethane glues worked best.

Clint