Adhesives, Long Term No Dryout - Page 1
Forum section: electronics / general

author: MrAl
author_rank: Super Contributor
timestamp: May 20, 2016, 07:46:02 pm
content: Hello there,Glue and epoxy is an important part of many fixes and builds for various electronic and non electronic products so i always have some of each around, in fact, a lot of that around. The problem WAS that over the years i find that i dont use each type of glue or epoxy that much, using some more than others, so some of it sits on the shelf for years without using after being opened for that first use. When i needed one of those products i would expect to go to the cabinet and pull out a tube or bottle and, well, use it to glue something. Too many times this didnt work because the contents were always dried, many times hard as a rock. I set out to find out what was going on.What i eventually found out was the main cause of the dryout was because of the top of the container. The top was the main problem as the side walls usually would not allow air inside. The top never seals completely, even when it is tightly screwed on or whatever.There was one exception, Elmer's Glue. The only people that seem to know how to make an air tight top. Everything else dried out over one to about three years. Elmer's Glue uses a top that sticks up through a hole or a tongue that sticks up though a slot in the top. The tongue type keeps the glue liquid for years, maybe as long as 10 years, while the tiny tip type works good too as long as the tip does not get damaged. I dont have any life data on the tip type though only the tongue type, which keeps the glue liquid for maybe 10 years.My goal was 5 years for any type. What i got i think reaches that goal, and the solution was very simple: make a new top.That sounds difficult because tops are not that easy to make, and if you really do want to make one you'll have to design it like the Elmer's Glue tops or something like that, but i found a simpler solution. It's not as convenient as having a quick seal top, but it works very, very well.The trick is to make a new top out of hot glue. The hot glue is applied over the tip of the glue spout, and making sure it contacts all areas around the tip it prevents air from getting into the tube or bottle. I've had silicone caulking last for years like this, when without it it would dry up after one year, or at least clog up the nozzle very badly making it hard to reuse.There is an alternative however, to make it a little easier, and this is actually what prompted me to make this post today. I opened a tube of silicone caulk today and found it was perfectly intact, ready to use, with not a hint of dryness anywhere in the tube including right under the cap.The alternative is to make a hot glue gasket. By applying a small amount of hot glue right under the area of the tube where the cap fits on, then screwing on the cap and letting it dry. The small gasket keeps it air free for years. The tube i tested today was sitting in a drawer for about two or three years, and no hint of drying whatsoever. The gasket can be reused, so you dont have to keep pulling out the glue gun.Note that this tube did not have a long spout like some of them have, just the screw on cap. If it has a spout you'll have to experiment with that yourself as i could not test every possibility.What else i have not tested yet is the push tube type epoxy. That has possible air leaks at the tip and at the gasket where the plunger seals, so that might not work, but the squeeze type tube will probably work out good.Good luck, and if you have any experiences with this in the future please post your results here and the product type and container type so we know what it worked on. I suspect that it works on any product that has a good enough outer container to begin with, just a problem with the cap air seal.

author: nukie
author_rank: Frequent Contributor
timestamp: May 25, 2016, 04:53:56 am
content: I find metal squeeze tube with screw cap type epoxy last a longer time. Pop it in the fridge you can go almost forever.