Sciencemadness Discussion Board

RBF Male joint

pneumatician - 31-5-2017 at 17:20

where I can buy a RBF (2L, 0,5L) with the joint male? 24/40 or 29/32

TIA

j_sum1 - 31-5-2017 at 17:46

i found these on a quick search:
http://www.ebay.com./itm/Pyrex-Boiling-Flask-Round-Flat-Bott...
http://www.ebay.com./itm/Lot-of-3-Kontes-500mL-Round-Bottom-...

s-l300.jpg - 9kBs-l300.jpg - 5kB

Or you could get one custom made pretty easily.

[Edited on 1-6-2017 by j_sum1]

JJay - 31-5-2017 at 18:30

Why would you want one?

Praxichys - 31-5-2017 at 18:47

Use a double-male adapter and you can attach any normal flask you want to it.

http://www.ebay.com/itm/Glass-Distillati-on-Adapter-Connecti...

j_sum1 - 31-5-2017 at 19:00

If for some reason you wanted to go straight from flask to condenser and minimise joints, then I guess it would be useful.
But I am interested in what kind of problem might be solved with this setup that could not be solved some other way.

DJF90 - 1-6-2017 at 00:04

This is a fairly standard arrangement for Schlenk tubes and flasks. Don't think I've ever seen one without a tap on the side though.

[Edited on 1-6-2017 by DJF90]

pneumatician - 1-6-2017 at 13:11

Quote: Originally posted by j_sum1  
i found these on a quick search:
http://www.ebay.com./itm/Pyrex-Boiling-Flask-Round-Flat-Bott...
http://www.ebay.com./itm/Lot-of-3-Kontes-500mL-Round-Bottom-...



Or you could get one custom made pretty easily.

[Edited on 1-6-2017 by j_sum1]


first is a 1000ml Male 29/42 Joint, flat bottom and used, sorry I need new never used.

second is 500mL Round Bottom Flask for Rotovap used too, 34/45, 34/45??? what the hell is this? :)

no, I could not get one custom made pretty easily. I talked with some guys, and after some point no more replies, others the quality of some items purchased for QC reasons is not enough for my. I need the most perfect joint and some items from china glassblowers are very bad. Stoppers "dance" in the female joint, others with the joint too much short or too much long...

Amos - 1-6-2017 at 13:32

I will second Praxichys's suggestion to use a double male adapter. It's cheaper and you have a solution if you ever need to do this down the road with a different-sized flask.

pneumatician - 1-6-2017 at 13:37

Quote: Originally posted by JJay  
Why would you want one?


I want a HERMETIC closure for volatile liquid, so the question is, exist some glass item offering HERMETIC closure? I have the idea, well the liquid fly but with a male joint can't escape between the walls of the joint. After the volatile liquid pass this point I think is in the superior piece condensed so can't escape in vapor form and fall again in the RBF and the cycle start again (circulation). Well perhaps some liquid is lost when falling between the joints but a lot less than putting the female in the lower place, no?

I can't use a cheap RBF and close the mouth with fire because is for plant tintures and the risk of boom is too great, no? :)

so I need something with the round bottom, all glass, new and offering HERMETIC closure!!

I see this "pressure bottles" from chemglass... but the stopper is not glass, right? what use have this? the closure is HERMETIC??


j_sum1 - 1-6-2017 at 14:37

If you don't mind paying for some shipping to the US, you might try contacting Chemetix. Actually, you might PM anyway. He will probably know of good glassworkers closer to where you live if he cannot help.