Another dewar thread, ok here we go lol.
You have to weigh out the cost of LN and how many knives you do. I do a TON of knives and im 1000% happy with my choice of going with a opening just over 2". I have a very large glass vacuum flask for anything larger and it's also very nice. it's like 6" wide and like 13" deep I think and works perfectly. Stay away from the cheep made in china dewars as your going to be refilling them way sooner than thy say. Also stay AWAY from dewars that come with a little blanket or jacket around them. This is a sign of a cheep dewar that's not built properly, your dewar should not be cold on the outside as its vacuum insulated, you loose all your nitrogen out the top through the mouth that's why larger opening loose it faster. I generally get a few hundred blades out of mine before I have to refill and it keeps for a very long time. look for a dewar that has an evaporation rate of around .09L/D, that's about the best I found in my research. My dewar is made by VWR "cryo pro", but thy make a few different dewars and mine is the CC-2. Stay away from the VWR L series, Thy are cheaper and have a much higher evaporation rate. I have been keeping my eye out for a CC-3 but even used thy are around $800 minimum plus shipping. My cc-2 has a 2-3/16" opening and holds 20L where the cc-3 is 2-3/4 and holds 30L. but if your not doing hundreds of knives a month your not going to need something like that. Honestly I don't think there is a better dewar out there or knife makers then the VWR CC-2.
