I just bought a 250ml Kimax filter flask, and after the first time using it, I noticed a strange mark on the bottom. I'm not sure if this existed
before the filtration, but I didn't notice it. The paper did seem to get clogged and pulled a heavy vacuum, however. Can you tell if it's a crack that
might cause an implosion, or if it's just a normal mark?
garage chemist - 1-1-2011 at 17:09
That's an imperfection from the molding process. No reason to worry. You are wearing protective glasses during all vacuum work anyway, don't you? entropy51 - 1-1-2011 at 17:12
You can also wrap a thick towel around the flask while it's under vacuum to lessen (but not prevent) any shrapnel hazard if it should implode.bob800 - 1-1-2011 at 17:28
You can also wrap a thick towel around the flask while it's under vacuum to lessen (but not prevent) any shrapnel hazard if it should implode.
Thanks for the suggestion. I'll try that from now on.Magpie - 1-1-2011 at 17:34
You can also wrap it in duct tape. I suppose clear shipping tape would work too. I've seen this done with duct tape in some of the teaching labs.Ozone - 1-1-2011 at 22:26
It does not look like a crack to me.
O3bfesser - 2-1-2011 at 07:31
I work at a grocery store, and have found that the floral department throws away hundreds of little plastic mesh tubes. Apparently, daisies and some
other flowers come with these tubes to keep them in shape or something--WHO CARES! I think they're HDPE or PP. I like to use the mesh to put over my
more fragile or expensive flasks, bottles, and reagent jars. It seems to keep them from getting any glass on glass contact--no nicks, chips, cracks,
etc. It's pretty light weight mesh, but very stretchy. I haven't had a flask implode yet, but I'm curious to see if it would contain any of the
glass. It's thin enough that I can even read the reagent labels through it.
The produce department sometimes gets pears wrapped in a similar polystyrene foam mesh. I slip these over my round bottom flasks before I set them in
the bin for storage. Not as good as the floral stuff, but good thermal insulation properties.
Sometimes when I've bought Dewars or desiccators on eBay, they've come with a very stiff and strong looking plastic netting over them. I'm guessing
this stuff would do wonders for imploding flasks, if anyone can source it.
[end of meandering rant]
[edit]
For tape, wouldn't elasticity be desirable? Clear packing tape seems to tear easily. Duct tape has fiber reinforcement. Good quality electrical
tape (not the cheapo stuff) is extremely elastic, and might be ideal.
