Alumilite going bad?

[McBryde]

Well, I boutght some Alumilite from Hobby Lobby the other day to try out and experiment with some, and i'm wondering if it had gone bad, or it was just my rookieness. The first mold poured, the blanks flaked apart, and were very brittle. The second mold took a while to harden (30 minutes), and it was pretty brittle on the edges, but eh center was ok, and it was not flaking like the other one and breaking with only a little pressure. The 3rd pour, was a thicker pour, but it has been in the mold for about 4 hours now, and it has not hardened completely. It has spots on the bottom where the blank feels mushy inside of it. It has also depressed, or almost collapsed in the middle on the botom.

Can Alumilite go bad? I don't know how old this was, or how you would even tell, but I was just wondering. Or is there something that I may have done wrong?

Thanks,

Emerson

 

[1080Wayne]

If all three casts were the same mix of ingredients , the slow setting ones were probably not well enough mixed . On a clear pour , the components must be stirred until the blend is water clear , which usually takes about a minute . If pigment has been added , you can`t see this , so I would give it another half minute or more . Volume of pour also affects stirring time required . Pigments and the amount of them can also influence setup . Moisture is an absolute no-no . Did you pressure cast ?

Brittle is not an Alumilite problem that I know how to create . Mushy spots leave me thinking of air entrapment or inadequate mixing . A cast will normally be thumbnail indentable for several hours . I would prefer to leave one for two days before turning it . I have cast one dry material that usually take two weeks to harden .

 

[kronewi]

When I mix up Alumilite it have to stir it for about 30 seconds. It becomes clear, no haziness in it. I use clear cups so I can see when it is mixed. If I add a mica or coloring I add it to Part A first, then mix in part B. Either way it requires a good 30 seconds of constant stirring.

Another point on the stirring, don't make it a fast stir. Just a constant gentle stir, scraping the sides and bottom will suffice. The harder you stir it the more likely you will add unwanted bubbles in your mix.

Kevin

 

[TomW]

Do exactly what Curtis says here.

If you still have a failure, I'd suspect bad product (but I'll bet you dont have a failure after this).

Tom

 

[McBryde]

This was the tan one, not the clear. It also had dye mixed in with it, so seeing it was not an option. I don't know how long it had been sitting on a shelf, but the crubleness of the one cast was conscerning. I have used it all up, and have no good blanks to claim from the $30 in resin. Not good!

E

 

[PTsideshow]

I knew I just read the answer some were.

What is the shelf life for Alumilite's casting resins?
1 year, however as long as the resin has been kept free from moisture, it may still be good to use for much longer periods of time. Resin that has been as old as 4 and 5 years old works with no problems as long as it has been sealed and free from moisture.

Here is their web site the FAQ section
And for the usual disclaimer the link is for informational purposes only not advertising!
:clown: