Sciencemadness Discussion Board

question regarding stoppers and tubing

frinj - 4-6-2010 at 10:58

If I want to run rubber tubing from a rubber stopper (with one hole in it) do I need to make the hole myself, or are these one-hole rubber stoppers adequate? On the internet, the one-hole stoppers seem to have very small holes, maybe the right size to hold a thermometer, but maybe not as wide as I'd want to ensure adequate ventilation of gases from my reaction.

Is there a one-stop-shop that sells rubber stoppers with holes as well as tubing to fit those holes?

bahamuth - 4-6-2010 at 11:17

Here's a tool that will help you make the hole sizes you want:

http://cgi.ebay.com/7-PIECE-CORK-RUBBER-STOPPER-BORER-SET-/3...


Also, you would perhaps have some glass tubing through the stopper/cork to attach the tubing to.

Natural rubber stoppers are the cheapest and are fairly chemically stable IMO. Silicon i hate... Butyl would be best but are expensive if they exist..

Also, it is best to buy rubber stoppers with no holes in them, gives you better starting point if you want several holes/offset holes etc.

The WiZard is In - 4-6-2010 at 12:08

Quote: Originally posted by frinj  
If I want to run rubber tubing from a rubber stopper (with one hole in it) do I need to make the hole myself, or are these one-hole rubber stoppers adequate? On the internet, the one-hole stoppers seem to have very small holes, maybe the right size to hold a thermometer, but maybe not as wide as I'd want to ensure adequate ventilation of gases from my reaction.



If what's left of my memory is correct... the holes in rubber
stoppers is designed to accept 7mm od. glass tubing.

If you freeze your rubber stopper in LN2 then you can drill a larger
hole.

Or just use the previously recommended hole borer.

Use a cork, a run of the mill drill will make any size hole you desire.

The WiZard is In - 4-6-2010 at 12:15

Quote: Originally posted by frinj  
On the internet, the one-hole stoppers seem to have very small holes, maybe the right size to hold a thermometer, but maybe not as wide as I'd want to ensure adequate ventilation of gases from my reaction.



--------
Buy a three hole stopper.