The strange case of the disappearing rubber solution

[Gixxerman]

I was in the process of putting the MTB in the back of the car Saturday night ready for the BikeMania Challenge event the following day, when I noticed that the front tyre was flat. So I had obviously pick up a p***ture last weekend when I last rode it. Must have been near home as I didn't realise on the ride.
Anyway, tyre off and pucture found, and culprit thorn removed from the tyre.
Went to put the patch on. Opened the rubber solution tube, which quite full as I have only used it once before ages ago. Only to find that all it contained was air. I squeezed the whole tube out, but not a drop came out.
So where did it all go? The tube cap was on and tight and I have no reason to suspect that it wasn't air tight.
So I had been carrying round a tube of solution that was no use for ages now. Good job that I also carry a spare tube, else a p***ture in the middle of nowhere would have been disasterous.
I fitted a spare tube and completed the event.
So can rubber solution evaporate?
Should I replace the solution at regular intervals? If so how often?

 

[Ajax Bay]

Yes, glue eventually evaporates, even with the cap on and even with the 'new' seal intact. You often can't tell - which is a pain. Best practice is carry some self adhesives as well and replace the (small) tube of glue at least annually, with a newly bought tube or an opened one - that way you at least know that there was glue in there at the start (eg of the year). You're right: you don't want to find this out mid way through a ride. And you never know when the p fairy might strike twice.

 

[Gixxerman]

Thanks Ajax, that explains it. So I might save up a few p***ctured tubes and mend them all at once. Then buy a new tude of solution for the kit I carry, and leave the opened one at home. In the highly unlikely event that the p fairy doesn't visit me for a least a year, I will buy a new tube of solution as a matter of course.

 

[Ajax Bay]

Glue is for home (or if on tour - overnight) mending, not by the roadside imo. Self-adhesives work and you're not hanging around for the glue to dry.

 

[slowmotion]

Chemicals evaporating out of even un-opened containers is a very common problem. I once had to put some polyester resin anchors in a brick wall. Having drilled and cleaned out the hole, I squirted in the two part resin from an unopened cartridge and poked in the steel studding. Normally, they set solid in about five minutes, but these ones never did. One of the two components in the cartridge had migrated elsewhere and the resin was entirely useless. It's really important to look at the "Use By" date on the packaging.

 

[Tom B]

Glue is for home (or if on tour - overnight) mending, not by the roadside imo. Self-adhesives work and you're not hanging around for the glue to dry.

I take your point and use scabs at the roadside (and at home, and at work), but even with SA patches you do have to wait.
The adhesive still needs to set/cure/get to work the only time i have had issues with scabs is when I have been too impatient and not pressed them/left them for 2-3 mins before inflating.

The other thing with scabs I find is that they don't like moisture and work better when warm, so put them in your trousers whilst stripping the wheel and before using on cold days!

*my experience is limited to cheapo weldtite patches.