silicone backing mats

by **Aussiedownunder01** » Sun Jun 02, 2013 3:07 pm

I see 1/16 thick silicone baking mats in harris scark today would they be of for gaskets they seem flexible

by **Aussiedownunder01** » Mon Jun 03, 2013 8:39 am

I think i will re write that to make sense [posting while drunk :o ]
I see 1/16 in silicone cooking mats in Harris Scarfe
Would they be any good to cut down for gaskets

by **BackyardBrewer** » Mon Jun 03, 2013 9:12 am

Sam posted a few pix a while ago of some various tests he did of silicone seals soaking in neutral. Some of the dodgy cheaper ones almost immediately leached out cloudy shit straight away, meaning there's no way that's something you'd want in contact with hot ethanol.

Maybe buy one sheet as a tester? Without knowing the brand or the material it's hard to say without a test to be sure.

by **Sam.** » Mon Jun 03, 2013 9:39 am

My tests were with a rubber sort of seal on a massive glass container.

I think it was Brendan did a good test with other things.

Reckon the baking sheet should be fine mate.

by **Aussiedownunder01** » Mon Jun 03, 2013 10:10 am

Ok thanks will get one and test it its not for me a mate got a still given to him its got a rubber top gasket

by **Brendan** » Mon Jun 03, 2013 11:26 am

Yeah mate, I tested the clear silicone tri clamp gaskets as well as the red silicone baking sheet from BigW.

The silicone is completely resistant to almost everything except acetone, which exists in foreshots.

When the silicone was tested in 100% cleaning acetone, they broke down within an hour.

But I have had some soaking in foreshots straight from the still for a month, and am only noticing a slight colour imparting now...it's your call, but considering foreshots will only be in contact for 20 mins or so, I now feel comfortable using it :handgestures-thumbupleft:

by **scarecrow** » Mon Jun 03, 2013 12:44 pm

I use them for a column to keg gasket.

Silicone Gasket.jpg

There is such a small surface area in contact with the liquid it's not worth worrying about.
Silicone has good ethanol resistance and it's OK for ethyl acetate and butanol etc, but not recommended for a prolonged soak.
I used to wrap them in teflon tape, but now I don't bother.
I've used the same gasket now for about 9 months and it's as good as. :handgestures-thumbupleft:

scarecrow