Sciencemadness Discussion Board

Filtration flask side-arm stopper ideas

Db33 - 13-12-2016 at 11:18

Can someone please give me an idea on what to use as a stopper for the side-arm/vacuum arm for a filtration flask? The reason i ask is because i have a filtration flask with a vacuum/side arm and a buchner funnel that has a vacuum inlet arm as well and i need to block one off. I swear i have seen em before but i cant figure out what they are called or where to buy them, can someone please guide me?

elementcollector1 - 13-12-2016 at 11:35

Put a piece of rubber tubing on, and tie it off tightly like a tourniquet? No idea if that'll work.

I guess another idea would be to get a 3-way splitter barb and hook both up to the same vacuum. Wouldn't change much, really, but it'd provide a vacuum.

PeterC - 13-12-2016 at 11:44

If you have access to very small rubber turnover stoppers(like the ones used for airless reactions) you could try those as long as you're not putting them under vacuum for long periods of time.

DraconicAcid - 13-12-2016 at 12:27

Rubber pastuer pipette bulbs.

Texium (zts16) - 13-12-2016 at 13:45

Just use a regular Erlenmeyer flask with the funnel like you're supposed to.

careysub - 13-12-2016 at 18:45

Plugging it with silicone caulk?

Db33 - 14-12-2016 at 08:06

i found alot of help with your guys answers! the best isthe eye dropper/pipette rubber.

My other question is can someone please give me a link to a place to get good thich walled vacuum tubing for distillations extractions?

PeterC - 14-12-2016 at 08:10

Quote: Originally posted by Db33  

My other question is can someone please give me a link to a place to get good thich walled vacuum tubing for distillations extractions?


Have you tried the hardware store? That's where I usually buy my tubing since professional suppliers of "vacuum tubing" (just thick or reinforced tubing) can get quite expensive.

Db33 - 14-12-2016 at 08:16

Quote: Originally posted by PeterC  
Quote: Originally posted by Db33  

My other question is can someone please give me a link to a place to get good thich walled vacuum tubing for distillations extractions?


Have you tried the hardware store? That's where I usually buy my tubing since professional suppliers of "vacuum tubing" (just thick or reinforced tubing) can get quite expensive.


i know all the tubing the hardware store has, i use that tubing for my condenser but the tubing im looking for is like reddish and looks like this
[img]https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcSdA9CaBlKFfW4r2ms81kTSRtKp4F4NMA2YCKqNRGe0FiPz1Zg2kQ[/img] ive seen it in many lab videos and it seems to be perfect.

PeterC - 14-12-2016 at 08:29

If you're in europe and have a business address, know Carl Roth sells: https://www.carlroth.com/en/en/Labware/Sampling%2C-Pumps%2C-...

Fisher in the states also carries Vacuum Tubing but that's in the hundreds of dollars so I would stay far away from that. My next bet on where to find good tubing would be an industrial welding or gas store since they often carry random types of tubing.

Db33 - 14-12-2016 at 08:36

Does anyone know the size of the average side arm? Its the same size as the arm on the vacuum adapter and on the vacuum pump, is it 3/8" ? Do i get tubing that is 3/8" ID ?

ElizabethGreene - 14-12-2016 at 11:42

I'm late to this thread.

Auto parts stores carry, for about $5 us, a set of rubber caps that are used to block off vacuum lines in cars.

While you are there, they also sell car vacuum tubing. It's made of a fiber reinforced rubber, and is designed to survive underhood temperatures and exposure to oil/coolant/gasoline vapor and liquid exposure. (and it's cheap!)