Dewar size

[upperguy]

So I've been reading for a while and researching and have been looking to get into LN2 for cooling and...well cooking. I got a line on a new dewar but it's 5L, seems like everyone has 30+ so I was wondering if it would be too small to really be useful? On a random factual note: 2.5L should be good for a gallon of ice cream;)

Thanks for any input guys!

[upperguy]

So I've been calling around and the smallest rental in my area(Philly) seems to be 160L.... That's a lot of ice cream! Anyway, is anyone familiar with a semi-local vendor that will rent small dewars? Advice on inexpensive fill locations would also be appreciated, I just got quoted at $3.6 as the least expensive so far.

[DrNip]

5 liters is small. You would need at least a 20 liter. Save your cheese and buy one instead of renting if 160 liters is all they have to rent.

[upperguy]

Lets say I got the 5L for now and decided to upgrade down the road, would people pass it by because it's only 5L or do you think there would still be interest in it? Also, are there any forums or classifieds besides ebay that people list them used?

[kikicoco1334]

dude you'll want at least 20 as a starting point

my first dewar is a 32L by MVE it's awesome thinking about buying another but i really think my mother may kill me :P

[DrNip]

I don't see the 5 liter being a hot cake. Try your states craigslist.

[upperguy]

nothing within 500 miles of me on CL. Do you guys know any places that rent smaller sizes? I've tried all the local Praxair and Airgas but the smallest is huge.

[GFDuke]

Nope. 180L would be the smallest you can rent. The place i get mine from only has 230L Dewars.

[MaadDaawg]

The 5 liter would literally be a waste of money, and I've never seen any for rent under 160L . Problem with renting is they gas off rather quickly so after a week or so it'll be empty even if you don't use it... which would really suck.

e-bay can have some good deals, and a site called LabX will occassionally have dewars for sale.

Good luck :thumbsup:

[kikicoco1334]

dude you'll want at least 20 as a starting point

my first dewar is a 32L by MVE it's awesome thinking about buying another but i really think my mother may kill me :P

i take it back...
i KNOW if i get another dewar my mother WILL kill me

how much is 180s? for rent?

[MaadDaawg]

Airgas I believe charges $1.50 a day rental, plus there is a $25 delivery/pickup charge each way, then the cost of the LN2. They will not go up or down any stairs :P

[upperguy]

Airgas wouldn't give me any prices without doing a credit application for an account.

[MaadDaawg]

These are the prices the Airgas here quoted me. From talks w/ other brothers they seem consistent. Difference is what you pay for the LN2.

[GFDuke]

Don't forget the hazardous materials charge you get from airgas too. And hell man. A week is strecthin it. The Dewar i got from Airgas emptied itself in 3 days pretty much. I got about 40L out of a 160.

[Patch]

Yeah, when renting big ones they don't understand what we use em for and tend to give high pressure valves for people who want N2 gas. When I rented one the sucker popped off every 30 minutes, blasted practically across the room from the "liquid" valve, and I got about 80L out of it in a few days.

Apparently they can use low pressure valves that are more conducive to our use, but they need to know what you're talking about and be willing to give you a low pressure valve on the tank. The LN2 I've drawn from the 230L tanks at MSI and ASUS events comes out at a much lower pressure.

Don't get a 5L. Unless it's just to transfer in small amounts from a larger dewar at home. I have 4 dewars (30L, 25L, 20L, 10L). I appreciate the portability of the 10L and sometimes transfer into it from the 30L when I know I'll need to quickly refill my thermoses when running multiple pots.

[upperguy]

Just out of curiosity, how much do used 10-20L Dewars seem to go for? I can't find a solid answer with ebay being all over the place.

[MaadDaawg]

:rofl: forgot the hazardous material handling charge :rofl: our government in action :rofl:

Patch is right - same thing my airgas guy told me about getting a lower pressure rental

As far as pricing, they're pretty high and depend somewhat on what they do or don't come with. some have a cork stopper on top which is less $$ and some have a dispensing unit which is more $$

My 35 cost me about $450 plus shipping and my 50L was about $500 plus shipping and both came with the dispenser and trolly - depends a lot on what you happen to luck out finding :P

My guess is that 10 - 20L will still run you $300+

[K404]

To give some context, Vince uses a 4L dewar as a flask for 4-way + CPU ;)

5L is basically pull-down and MHz stabilisation, very little benching :p


If you have the patience, Ebay has some great deals on dewars because if they're auction format, they go for next to nothing... just make sure you ask if the vacuum is in tact

[MaadDaawg]

To give some context, Vince uses a 4L dewar as a flask for 4-way + CPU ;)

5L is basically pull-down and MHz stabilisation, very little benching :p


If you have the patience, Ebay has some great deals on dewars because if they're auction format, they go for next to nothing... just make sure you ask if the vacuum is in tact

I got mine on e-bay with assurances that they were sure the vacuum was intact - if not I could return. No probs with either though. If you see one that's a set price or best offer, make them a decent offer and they may take it ;)

[DrNip]

Hey but welcome to the forum! :Hi: