Is there a shelf life for modelers glue?

[McColm]

Hi Guys,
Does the glue/cement that you buy in tubes or blue/yellow plastic squeeze containers ever loose their adhesion?
I know once opened they do, but is there a shelf life?

[Hobbes]

In my experience, no. I'm still using the same bottle of Uhu Plast I bought 10 years ago. CA glue does harden over time; I had to throw out two bottles that were about 4 years old, so these days I buy Bison squeeze containers, their shelf life is long enough that I can empty the container before it goes bad.

[PR19_Kit]

I use Revell Contacta in the blue containers with the needle type applicators as far as I can see that lasts for ever. Liquid glue, like Slaters Mekpak and Humbrol Liquid, does tend to evaporate over time, but you know when it's reached its shelf life because it's vanished..... 

[JayBee]

While I do not know the exact percentages, but most liquid "glues" are in fact mostly solvent.
Mekpak is the one exception in that it is pure solvent, and if you leave the lid of the bottle overnight it will have evaporated by morning. (Unless you are in a very cold climate).
Humbrol Liquid Polly has a small amount of plastic in it's make up.
Revel Contacta has a greater amount.
The more the plastic, the slower the deterioration of the "glue".
Tube glues are thicker as they have more plastic in them.
The more the plastic in the formulation, the slower the solvent will dissolve.

Hope that helps.

Jim

[McColm]

Thanks.

[Gondor]

Slightly off topic, but what is the best method for keeping the Revell Contacta clue nozzle clear? The one's I have always appear to be blocked 

Gondor

[major]

Slightly off topic, but what is the best method for keeping the Revell Contacta clue nozzle clear? The one's I have always appear to be blocked 

Gondor

I have that problem to. The only way i've found to clear it is to take the needle out, hold it in a pliers, and heat it over a naked flame till it glows red!
Reckon i don't get enough modeling time during the week and thats why it clogs.

[PR19_Kit]

I dip the tip of the blocked needle in some liquid cement  and then poke a short length of 5 amp fuse wire down it. That usually does the job.

[rickshaw]

Piece of wire works for me.

[Hobbes]

yep, I use a piece of wire as well. It also helps to hold the container upright and squeeze out the last of the glue when you're done.

[Old Wombat]

I use Humbrol poly cement (as well as Tamiya liquid poly, CA, 2-part epoxy &, occasionally, construction adhesive), which comes with a long cap over the metal dispensing tube, but I can't remember if Contacta uses the same system.

For me:

I find that a thin piece of wire (I generally use a partially stripped piece of plastic-coated tie wire) clears the tube nicely but, to prevent clogging whilst in storage, I keep the bottle capped tightly with the tube angled down, this way the solvents in the liquid prevent glue drying in the tube & clogging it.

[Mossie]

I have another method.  If you have a gas hob, take the nozzle out of the bottle and using tweezers, hold it over the flame.  The blockage burns off quickly, then run it under a tap or in a cup of water to cool it down before handling.

[zenrat]

0.5mm wrapping wire (that I use as 1/25 spark plug wire) is the perfect size to shove down the tube to clear blockages.

And of course the tube will remain clear and unblocked all day and then clagg up just as you've only got one free hand because you're holding a tricky assemblage together with the other one...

[NARSES2]

I'm another one who uses the hold in a gas flame method on the few occasions a Contacta tube has become blocked

[Gondor]

I shall try the gas flame method again tonight as I believe I have tried it before. No harm in trying once more though!

Gondor