Strange Glue Behavior

[waaytoomuchintothis]

I hope this post stays on the new posts list longer than 2 hours, which is how long mine have been up there lately. Some things stay for days without traffic, lately most of mine just vanish from the new posts list in no time.

Anyway, for those who actually get to see this one, I have a strange report. I use Loctite gel superglue, and toward the end of a bottle, it will grip so fast I don't have time to position stuff, and a minute later, the next thing I glue seems to take forever to get a tack grip. The materials are always clean and dry, the materials are very similar (all plastic), and yet this oddball thing happens at the end of a bottle.

Is there any use in shaking superglue?

[Modlerbob]

As far as shaking superglue my answer would be not that I know of. I rarely get to the end of a bottle of any type of superglue as it always ends up hardening to a solid or gets so thick it won't flow.

[goosenapper]

I'm with Bob on this one. Regular super glue always dries up before I reach the end of the tube.

I've switched to Gorilla Glue super glue for this reason. Their bottles all have a metal pin built in to the cap that keeps the spout clear, and their glue tends to have more give in crashes. I've never had a piece break off since switching to Gorilla Glue, and that's saying something considering the crazy speeds and impacts that occur in the digital races I'm involved with. But more relevant to your topic, the bottles don't dry out and last until empty.

[Fitzy]

How super glue works

The main ingredient in super glue is a chemical called cyanoacrylate, an acrylic resin that forms a bond (cures) almost instantly
The only trigger it requires are the hydroxyl ions found in water
Traces of water are found on almost everything and in the surrounding air, which causes the glue to become sticky
It works best in moist conditions, although it is not advised to start gluing on a soaking wet surface

[waaytoomuchintothis]

So, your theory is that somehow the thing I glue first is somehow more moist without being wet, Fitzy?

I will say, this never happens in reverse. It does actually too well the first time, then it acts like water for long enough for old fashioned model airplane glue did to get a tack grip the second time on another piece, maybe 30 seconds later. The end result is the same. Same grip, same strength. It just seems weird.

[Fitzy]

After you open a new tube / bottle of super glue it gets moisture from the air so the longer it's around the quicker it dries in the summer time here we have a lot of humid days and the super glue dries on contact in the winter time here from the dry heat indoors I use accelerator to get it to cure I have always found that the original super glue that comes in the green & white round cylinder last till the end I think it's because it gets sealed in that tube and wont collect moisture

[Abarth Mike]

I'm also with Bob on this. :angry-tappingfoot:

What we here in the tropics have discovered? We have small 25 ml white bottles of superglue. For the princely sum of 60 cents.

We do not use the nozzle. We unscrew the complete cap and dip a toothpick into the glue and then apply a drop of glue from the toothpick. Afterwards, we replace the cap.

This makes the glue last longer and mostly prevents the whole lot going solid as we are not relying on the "nozzle cap" to seal the bottle we are always using the screw cap.

Of course this sometimes results in knocking the glue over :roll:
:idea: So better if the bottle is stuck to the desk with BluTack

[waaytoomuchintothis]

Now I get you, fitzy. That makes a lot of sense, as does Mike's and Bob's practice. Where I notice the difference the most is when I telescope one size of plastic tube in another to make a screw post. Recently, I did the front post, set it aside, then did the two rear posts, and one of them stuck before it was all the way telescoped, all within 20 seconds or so, and each one was done one at a time, not having any real difference in air exposure. So when I squeezed the grips on the bottle, it is completely reasonable that an area of the glue that had contacted moisture in the air could have come out first, then the next two might be fast or slow, depending on which part of the glue pool inside got to the nozzle first. (if that sentence confused you, imagine what it did to me writing it!) But I think that solves the mystery. Thanks, guys.

I have to say, I miss real model airplane glue. If idiots want to kill them selves with something, they will find something else to do it with. Meanwhile, we have to go through a lot of inferior substitutes to keep the idiots from getting their hands on our glue, blast it. And yet my son with cerebral palsy can't have medical marijuana that is impossible to get high on. Grrr.

[Kemtronracer]

I use the same glue all the time. Try storing the bottle upside down.

[waaytoomuchintothis]

Another good idea. Thanks Kentron. I've been around this stuff forever (I remember those huge Kemtron motors), and I keep learning new stuff, good ideas just keep coming in this hobby.

[Abarth Mike]

[waaytoomuchintothis]

I use plastic tubing that is a tight fit, so the resulting screw post is good and stiff when it sets up. I use the gel type because I'm old, and I tend to make a mess with the watery stuff that will slip into little spaces. Although using your toothpick idea with the watery stuff might work for me.