Sciencemadness Discussion Board

Addition funnel frustration

coherent - 28-6-2023 at 05:22

I've been having a very painful time getting consistent drop rates from my addition funnel, it has a glass stopcock and seems to be very prone to freezing up but also it's extemely difficult to get it set to the desired rate.

Is there any trick to it? lubricant or similar to deal with the lockup and make the action of the stopcock more smooth?

Texium - 28-6-2023 at 05:40

Are you not greasing it?

coherent - 28-6-2023 at 05:43

Quote: Originally posted by Texium  
Are you not greasing it?


Sounds like that would be the problem, is silicone grease a suitable choice and are there limitations I should be aware of?

Cheers!

Texium - 28-6-2023 at 06:31

Silicone grease is fine. Don’t use too much, and try to avoid getting it into the hole in the stopcock. It’s impossible to avoid a little grease contamination in your material whenever you use a greased glass stopcock though. Because of that I try to avoid glass ones whenever possible, and greatly prefer the PTFE variety since they don’t freeze and don’t require grease.

Grizli7 - 17-12-2023 at 06:47

or soak the crane for a funnel substance