Dear Lab Guy,

I have  a 18” table top Buchner funnel.  I have air leak where the plate sits inside at the wall. Is there something I can use to seal this?
Best regards,
Josh

Hi Josh-

Since you are mentioning "air leak"’ between the funnel plate and wall, I am going to assume 2 things based on answering many similar questions in the past:  1.  your product is the filtrate (i.e. the liquid at the bottom of the funnel after going thru the filter) and, 2. that you are using a Buchner funnel with a removable plate.

I wish I had an easy fix, but in this case, the vacuum suction is the defining factor – and if you have a funnel with a removable plate, even the tightest seal will not prevent unwanted matter from finding its way down the side walls of your funnel.

Whenever your end product is the filtrate, for example, plant extractions, it is recommended that you use a Buchner Funnel with a FIXED plate.  This means that the filter plate is permanently sealed (welded) in place, thereby eliminating any chance of contaminant seeping down along the wall.

If however you own a REMOVABLE plate Buchner funnel or in a rare instance the weld on a fixed plate has been compromised, I recommend contacting a local area business specializing in fabricating plastic tanks and barrels to see if they can provide welding services. 

Also, depending on the condition (how clean) your funnel is and what it has been used with, you may be able to arrange shipping it to SP Scienceware for permanent plate welding.  For more information on this service or to confirm which funnel is best for your purposes please contact our Customer Service Department at 800-423-5278.

Thanks for writing and please feel free to write back if I can help in any other way.

Lab Guy