Not All Silicone Cups Seem To Be Equal

[Jig Man]

Several days ago I posted asking about them. I decided to go to the local Bed Bath and Beyond because they had 2 listed. When I got there the "good" ones had to be ordered. The card said they could withstand like 560° and had a built in green non slip section.

They came and I tried them out yesterday morning.

I heated new plastisol for 1 minute then stirred it and put it in for 30 seconds. During that 30 seconds I heard a small explosion in the micro. I pulled out the cup and there were bulges on both sices and some of the cup had come apart and was in the plastisol.

I poured that out into the other new cup and gave it a 30 second heat up. It blew up just like the first one. So I guess I'll go to Ebay and see about some of the other recommended cups.

[mark poulson]

I'd sure take them back to Bed Bath and Beyond. That stinks.

[TBaits]

I would too. They will take back ANYTHING, I used to work there.

[mark poulson]

Check the NorPro cups at this link:

http://www.norprowebstore.com/Search.aspx?SearchTerm=silicone+measuring+cups

They hold up fine for melting plastisol

[bobv]

Check the NorPro cups at this link: http://www.norprowebstore.com/Search.aspx?SearchTerm=silicone+measuring+cups They hold up fine for melting plastisol

Those are the ones I got from Amazon, they do work good. Those others must not have been 100% silicon. Perhaps the non-slip section was something else or had air trapped in it?

[Jig Man]

Check the NorPro cups at this link:

http://www.norproweb...+measuring+cups

They hold up fine for melting plastisol

Thanks Mark. I ordered some of them today. I'm looking forward to getting them and quitting the glass.

[mark poulson]

Good for you. I hope you like them.

The cup does get hot when it's heated, but not as hot as the pyrex, so it hold heat much longer.

When I pour, I wear a leather glove on my left hand, which supports the cup, and hold the top of the cup pinched with a big bag clip-type paper clip, to form a smaller pouring spout.

I use a folded over metal clothes hanger for a stir stick, and leave it in the cup when I'm pouring, behind the clip, so I can stir my plastic as I pour.

I guide the spout with my right hand, and also stir with it.

Just go slow, until you get the feel for it, and never leave the metal stir stick in the cup when you reheat the plastic.

Having several cups makes pouring laminates in top pour molds easy.

If you want to top pour laminates, stagger your heating, so the plastic in the first pour can cool a little (maybe a minute or so) before you add the second, or they will mix too much. Waiting time will vary according to how hot you pour (I try to pour at 340) and how deep and thick your first pour is. For my larger swimbaits, I wait a little longer.

Good luck.

[pigdestroyer]

Just curious. Why are these silicone cups better than the glass? I have been using the glass for years with no issues.

[Jig Man]

I'm getting them because the guys say they cool a lot slower than glass. I want to cut down on reheats.

[SHK]

Ever set a hot pyrex full of plastic on the cold metal table of your drill press?

I can see the allure of silicone.

nope but i do set it on a cold stainless bench daily no issues yet, going like this for a couple years

[smallmouthaholic]

http://www.soapdisharchives.com/forum/index.php?showtopic=57949

Two years ago I removed a hot Pyrex container of plastisol from the micro wave and was stirring it @ waist height when it exploded like a hand grenade. I will NEVER use a Pyrex cup again in the microwave w/ plastisol. I use borosilicate lab -grade,measuring cups from the Container Store

[mark poulson]

I'm guessing the sst table is just covered with sheet metal, so it heats quickly without cooling the pyrex too much. The cast iron drill press table is thick, and a huge heat sink, so it probably cooled the bottom of the pyrex cup fast enough to cause uneven stress. Tempered glass doesn't like uneven stress.