On the subject of plummer's Teflon tape the only time I use tape is when I store glassware. I only use a 2" lenght and I don't wrap it around the
ground glass joint. I just pull it on top of the port and drop the glass stopper loosely on it...
The reason I do this is that it prevents dust from settling inside the vessel, and I like to keep stoppers associated with their proper vessel. Let's
face it, who hasn't misplaced a stopper that fits one particular piece of glassware, I hate wasting time searching for stuff!
As for the OP's question, I have no preference over glass/teflon stopcocks. Depends with what the glassware came with. The only thing is that if a
glass stopcock chips, then the whole piece of glassware is FUBAR unless you find an exact replaqcement. I was lucky enough to get my hands on a stock
of 8 sealed new teflon stopcock replacement kits, all my sep funnels have spares for a long time!
But good advice from Rosco, I will loosen the nuts to release a bit of the pressure on the rubber rings when the sep funnels are not in use.
Robert
--- Art is making something out of nothing and selling it. - Frank Zappa ---
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