Ptfe bellows

Has anyone used these before? I just broke my second laminar cold trap due to stress on the lower joint when the ice melted in the bowl under the rf and the weight wasn’t supported well enough on the trap, so crack. I’ve found these bellows that are meant to remove stress from joints, says it’s for medium to high vac. I’m just curious to hear any reviews, if possible. I want to put it between my adapter and trap.

Thay look like a good option, i dont have summit’s laminar setup i kinda figured that wiukd bw a problem. I am still 1” all the eay to the glass and i feel the way mine is set up works jusg as good if jot better than that one. I never get anything in my 2nd come trap and theres no wierd angles and doesnt have to be put together in a certain order or it wont fit. Give thise a shot, ill order sone too

Who made the setup you have? I have the vacuum takeoff and I’d been collecting my volatiles in the trap. I’m gonna start putting them in the rf, so I can remove them entirely from the system before mains.

I made it i would never spend 10k+ for s system. Theres always a bettwr and cheaper way to do everything . I do about 8ml a min jn just a 5l and 1 Edwards. Theres alot of other rhings i do that help speed things up, bur i do no pre or post processing unless asked for it by the person whos toll im running. What kind and size system are you running

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I am going stainless steel on the cold trap…never break it again.


Nice. I’m Frankensteining my 5l setup, the base is lab society mantle and boiling flask, fc5 head from summit and the laminar vacuum takeoff and cold trap from vacuum dynamics running on a Welch pro 8 and a roughing pump. I can’t get that type of flow going low and slow yet. Staying at 168-175 vapor temp, need a better stirbar and maybe a mantle with a stronger magnet.

I was also thinking about an ss trap, but I haven’t found a good one yet.

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Man, you need some more clamps and lab jacks to support everything. That bellow looks neat, sorry about your cold trap loss. If you had an idea for a custom trap I can fabricate it.


Cema insrruments is whoningot mine from

Yeah, it normally is on a cork stand, this time I had a bowl of ice under it and it wasn’t large enough to hold the stand, ergo the crack. Lesson learned.

Edit: it’s at the glass blowers getting fixed atm.

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Are you referring to the ss cold trap?

Ya i have tbere older one, before they made the one with wheels, thats the 2nd one last thing before pumps.

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