Poly cement expiration

[Guest]

Hello everybody, this is my first post here.

I've just started a new plastic model kit after a pause of several years (I'm a beginner), and I have a tube of Humbrol poly cement that I used back then. I suppose it's about 7 or 8 years old. I don't see any expiration date on the box or on the tube. Should I still use it or has its properties altered?

This is the kind of cement I am talking about:



Best regards

Dragos

[Guest]

so long as the tube is unused it should be ok... the active ingredient is the solvent, usually a MEK style solvent, this will if left open slowly evapourate away....

my recomendation is get some new cement or even some plasweld instead......

if you really cant bring yourself to throw this away do a test to see how effective the cement still is.... break off two parts of sprue ( the frame that holds the model parts) and bond them together with the cement.... you will then be able to see if its any good......

[wonwinglo]

Dragos,I have used really old tubes of poly cement and provided the seal has been tight then it should still be fine,as Guy has pointed out the main solvent can dry out leaving a somewhat thick gel in the tube,do a test piece first to see what happens on some sprue from a kit.

[Guest]

Thanks for the answers!

The tube was used but it is not dry. I glued several pieces and it works well, it only seems to dry faster once applied, than it used to.

[Guest]

If the poly cement still flows ok from the tube it sounds like the solvent hasn't evapourated so it should work fine.

On the subject of glues expiring - whats the best method of storing superglue? It irritated me when I purchased some Pacer Slo Zap and after about a month it's now unuseable as it's all stringy and thick!

I'd taken care to ensure the cap was seated properly and it also had an outside top which was fitted. I had the same problem with some Loctite Superglue too. For around £5 a bottle thats a bit irritating having to bin it after a couple of uses.

[Guest]

Alan,

Superglue life can be extended it it is kept in the fridge prior to use.

loctite seems to go off, (my experience is the same as yours), the cheaper small tubes eg 3 tube blister packs available from 'Pound Shops' seem to offer the best economy but the glues do differ considerably.

The best i find for keeping qualities are a brand called "Tufloc", come in three thickness's, set of three bottles for about £6.

J.

[wonwinglo]

Yes Alan I agree,I purchased some Starlock and that has now dried up after only a very short time,best not to buy the larger sizes for this very reason.

It does appear to have a short shelf life ?

[Guest]

I have bought a bottle of Model Master liquid cement for plastics, with a brush on attached to the lid. I have never used liquid cement till now. From what I have learned by searching modeling forums, this should be applied on joints when the parts are fitted together, or to strengthen the existing joints, by touching the brush along the edges. Is this the correct technique ?

[Guest]

I have bought a bottle of Model Master liquid cement for plastics, with a brush on attached to the lid. I have never used liquid cement till now. From what I have learned by searching modeling forums, this should be applied on joints when the parts are fitted together, or to strengthen the existing joints, by touching the brush along the edges. Is this the correct technique ?

Bunker made a thread on these forums about modeling basics and mentions the pro's and cons of liquid poly and poly cement:

http://www.scale-models.co.uk/showthread.php?t=2298&highlight=basics

The way I use the two - liquid poly is used where you have close fitting parts and is run along the joint after holding the item together, capillary action draws the poly into the gap. Poly Cement can be used to reinforce an assembly by running a bead the insides of a seam.

[Guest]

we also store cyano adhesives ... and sometimes upto 6 months, - we buy in bulk to get the best prices for the business, but the storage is important, we store it now in a cooler box in a chemicals store, in the shade..... the cooler box is an industrial style picnic type insulated box, we have in the past stored it in metal containers but if the sun shines ( and it does sometimes here in windsor) the cyano's would start to degrade, we once had 24 large bottles of black cyano 'cook' ( black as it had a rubber compouind in it to give it flex, and all 24 bottles were cooked in the warm temperatures.....) as a result we wrote off £400 worth of adhesive in one afternoons sunshine!

we find this little box about the size of a washing machine/ fridge allows us to store the cyano and the temperatures dont fluctuate greatly, also it contains any spills that may occur...

we store all our liquid cyano and our gel cyano in this box and since then we have never had one go off whilst in the box....

if you have a ' extra' fridge then its a good place to store it- but dont like like the idea of my cyano being in my 'main fridge' next to my beer or rump steak !