One of the more intriguing exhibits at this year’s Maker Faire Bay Area was Ben Krasnow’s liquid nitrogen generator rig. Ben built the entire assembly, for under $500, with parts he scrounged (over a year) on eBay.

In this video, shot at the Faire, intrepid reporter Circuit Girl, aka Jeri Ellsworth, interviews Ben. We apologize for the loud ambient noise and the gonging robo-Gamelan next door. Hopefully between the video, the above illo, and Ben’s blog posting, you can get the gist of his set-up.

(And yes LN2 can expand with explosive force and can burn living tissue. All sensible cautions apply.)

DIY liquid nitrogen generator

Gareth Branwyn

Gareth Branwyn

Gareth Branwyn is a freelance writer and the former Editorial Director of Maker Media. He is the author or editor of over a dozen books on technology, DIY, and geek culture. He is currently a contributor to Boing Boing, Wink Books, and Wink Fun. And he has a new best-of writing collection and “lazy person’s memoir,” called Borg Like Me.

  • http://twitter.com/en2oh Douglas Gourlay

    Hi Ben,
    Great projects with incredible detail in your documentation of the process and theory behind their function.  I built a Transmission EM in highschool for a science fair project.  The glassware was done by a very generous university glass blower! 

    I’ve looked on ebay for cryocoolers and as usual, the deals are few and far between.  There is a 7W refurbused Ricor for $1800 Or Best Offer! (new price is $12,000) There is also a unit from Israel that is listed as working but not getting cold.  Can you offer any insight into trouble shooting a broken cryocooler?  Easy to repair (helium recharge? or failed compressor?) or difficult?

    (BTW, I did my grad studies in dielectric chemistry but eventually went into anesthesia as a medical doctor.  I remember the Liq N2 plant with foundness.  More than a few “wine-scicles” were produced back in my masters year – much less during PhD studies :)