Dewar cover/cap

TMWH · 09-22-2009, 01:05 PM

Hi all.
I im looking into to buy a dewar, but the nice one i found dosn't include a cap.
The seller talks about that i could make my own cover. Is this working very bad if it work at all?
If some of you have done this before, please let me know how, and did it work

lesstutrey · 09-23-2009, 12:34 PM

it's got no lid, but how you gonna get the ln2 out, you need a withdrawal device, they act as lids in essence too.

~~K404~~ · 09-23-2009, 12:55 PM

The lid is just a plastic cap with a styrofoam block that fits into the neck. Its absolutely, definately and very deliberately NOT airtight

The lid is really to prevent splashes during transport if the dewar is rocking

TMWH · 09-23-2009, 01:39 PM

Thanx for answers guys! Will start with a home-made lid. Maybe buy a withdrawal device if i find out i need one

~~K404~~ · 09-23-2009, 01:45 PM

Id always say go for the withdrawl... even if ya find someone who can make you one. the real official ones are offensively overpriced

One slip while tipping a full dewar and....its a big mess to clean up depending on your work area.....

[XC] gomeler · 09-23-2009, 02:40 PM

Quote:

Originally Posted by K404

Id always say go for the withdrawl... even if ya find someone who can make you one. the real official ones are offensively overpriced

One slip while tipping a full dewar and....its a big mess to clean up depending on your work area.....

big mess? I spilled about 5 liters on my concrete floor and it just formed a puddle about 8 feet across for half a minute as it all boiled away

~~K404~~ · 09-23-2009, 03:07 PM

I did say depending on your work area

TheKarmakazi · 09-29-2009, 08:10 AM

I wouldnt waste the money on a withdrawal device, unless u just got money to burn. Save the $400+ and buy some hardware

I use a taylor wharton 50L dewar and have never done anything except tipping it (and Ive poured at least 1200L on LN2 form it). Only spilled once and it was only 2-3L so not a big deal.

Buckeye · 09-29-2009, 08:29 AM

No big deal unless that 2-3L landed on your foot and got inside your shoes

sno.lcn · 09-29-2009, 08:37 AM

That's why I bench with LN2 barefoot (actually in flip-flops)

Gautam · 09-29-2009, 08:38 AM

It's happened to me and it wasn't pleasant, walked with a limp for a couple of months...feet got badly blistered.

~~K404~~ · 09-29-2009, 08:42 AM

Withdrawl devices and trolleys sure as hell dont cost as much as whats charged for them. A local metalworker can make trolleys for a fraction of the price (or make your own)... and HVACs can make withdrawl devices.

Buckeye · 09-29-2009, 08:57 AM

Quote:

Originally Posted by sno.lcn

That's why I bench with LN2 barefoot (actually in flip-flops)

HAHA I bet you do, cuz your crazy !!

Quote:

Originally Posted by K404

Withdrawl devices and trolleys sure as hell dont cost as much as whats charged for them. A local metalworker can make trolleys for a fraction of the price (or make your own)... and HVACs can make withdrawl devices.

That is so true, if you look up what those cost new its crazy, even on eBay they can be cost a bunch.

I cannot picture tipping my 50L over when full and trying to get the LN2 into a thermo.

Kal-EL · 09-29-2009, 09:30 AM

I wore combat boots out to my first LN2 session

(felt like I was headed into battle anyhow)

sno.lcn · 09-29-2009, 10:25 AM

Haha that's like me wearing welding gloves the first time I handled LN2