Sciencemadness Discussion Board

On rubber stopper

Yttrium2 - 19-5-2021 at 19:40

Trying to find a rubber stopper that has a 12mm hole in the center,

I don’t want to buy a stopper borer, if I don’t have to, just the stopper. Additionally, I only need the one size..

Correct me if I’m wrong, but 12mm OD glass needs a 12mm hole, correct?

Would a tighter hole be better?


Don’t even know where to find a single 12mm stopper.

Sulaiman - 19-5-2021 at 20:41

Quote: Originally posted by Yttrium2  
Would a tighter hole be better?

A tighter hole is always better ;)

Something like https://www.ebay.co.uk/itm/173289539147?

zed - 19-5-2021 at 20:47

Buy the stopper borer. It only costs a few bucks, and you will find it infinitely useful.

A drill press can drill a hole in a frozen rubber stopper. But, the stopper borer is straight-forward.

Yttrium2 - 19-5-2021 at 22:02

Not sure if this one can do 12mm holes,

it is 13 bucks

Belowzero - 19-5-2021 at 23:14

A regular steel or wood drill works quite well actually.
Just hold the stopper in your fist and use a small size drill first, then use a larger drill for whatever size you require.
Slowly work up to max speed to get a smooth hole.

Obviously this is slightly risky.

[Edited on 20-5-2021 by Belowzero]

draculic acid69 - 20-5-2021 at 01:28

I've tried drilling rubber stoppers before and it's not an easy substance to drill.
Freezing is a must. Without Freezing it'll go to crap

Oxy - 20-5-2021 at 05:45

Stopper borer is a cheap and simple tool (DIY version may be made easily) but very useful.
I mostly use all-glass setups but there are some cases when there is a need to prepare a setup having 3 or 4 washing bottles. In such case a rubber stopper with 2 holes and glass tubes (can be made from cheap Pasteur pipettes) is very handy as wash bottle can be made from any flask.