Ben Krasnow builds neat things.

September 24, 2012 11:27 AM

Ben Krasnow shows us how he built a small hybrid rocket engine. Ben makes a lot of other cool things too, like astronaut ice cream, a DIY scanning electron microscope, and why not, carbonated fruit slices.
posted by joechip (14 comments total)

Thanks, this is really cool. I always wondered how they made astronaut ice cream.
posted by Ad hominem at 11:33 AM on September 24, 2012

1) I can't believe he didn't measure the thrust.

2) Does PMMA give off any toxic fumes? Or is combustion so complete that there's nothing left?

3) What happens when he consumes right through the side of the engine? Explosion or just loss of thrust? (I guess the latter.)

4) I really love that he did manual machining for the easy parts. So many hipster-makers (or whatever you want to call them) do CNC for everything, even when it takes longer that way.
posted by DU at 11:54 AM on September 24, 2012

Oh man, he also made an contact-lens-embedded LED that he put in his own eye.
posted by DU at 11:59 AM on September 24, 2012

Dude has a scanning electron microscope in his garage, over next to the spare tiki torches.
posted by echo target at 12:08 PM on September 24, 2012 [2 favorites]

After watching a couple more videos. I hate this guy, making me feel like I have been wasting my time when I should have been building rockets and scanning electron microscopes. Can we have some videos of people who haven't done shit just to balance this guy out? Maybe an 4 hour vid of a guy eating fritos and watching Sherlock series 2 in his jammies.
posted by Ad hominem at 12:16 PM on September 24, 2012 [2 favorites]

shop tour, for those of you who actually know what the hell is going on with any of this.

love his expression when trying the ice cream, smug intelligent bastard.

i don't really get how people become this handy to the point where they can just feel like building something and go out and do it successfully. is there a graveyard of broken stuff and catalog of near-death or near-maiming experiences?
posted by twist my arm at 12:16 PM on September 24, 2012 [1 favorite]

after failing to satisfactorily mix avocados and nitrous oxide, a youtube commenter:

TRY BACON! Bacon is full with fat and tasty!! You could never have too much bacon...unless you have cholesterol :/

Ben's response:

I have been doing some tests with bacon and N2O, but I haven't found anything too exciting yet. There has to be something. I mean it's *bacon*.
posted by twist my arm at 12:30 PM on September 24, 2012

confounded by pop rocks. reverse engineered from the patent, after 20 batches and multiple angles of attack, he still couldn't get them as poppy as the real thing. interesting watching the problem-solving going on, especially with his creating special tools to try different solutions.

first round draft pick for most post-apocalyptic scenarios, this guy.
posted by twist my arm at 12:43 PM on September 24, 2012 [2 favorites]

DU: What happens when he consumes right through the side of the engine? Explosion or just loss of thrust? (I guess the latter.)

You're right; it will lose thrust (or more precisely, thrust will be spread out in two directions: backwards as intended, and out the side at the hole).

It won't meet appreciably more oxygen when it gains more access to the atmosphere through the hole, so the burn rate won't dramatically increase (to form an explosion).
posted by IAmBroom at 1:14 PM on September 24, 2012

Ben also posts his videos and other projects at his blog. The Thirst Extinguisher was pretty entertaining.

I retrofitted a commercial fire extinguisher to hold and dispense beer. I brew my own beer at home, so it is fitting to have a homemade "keg" to hold homemade beer!

The extinguisher tank is stainless steel, and fairly easy to clean. The top unscrews, and leaves a 3" dia hole. The extinguisher was originally setup to dispense fluid (ie it has a downtube that connects the outlet to the bottom area of the tank, and a port on the top for adding pressurized gas). This is exactly what we want to dispense beer.

posted by zamboni at 1:20 PM on September 24, 2012 [1 favorite]

He said phase diagrams were really interesting and I believe him: Interactive phase diagrams from the Dissemination of IT for the Promotion of Materials Science department of the University of Cambridge.
posted by carsonb at 1:24 PM on September 24, 2012

This guy came on my radar when his DIY electron microscope was featured in Make Magazine (might still be the current issue on newsstands, if not the issue before the current one). He's got a lot of YouTube videos and has the coolest shop in the world. I likes his attempts to carbonate homebrew beer with Argon. I also appreciate he shows you stuff even when the experiment doesn't turn out as he had hoped.
posted by spock at 7:21 PM on September 24, 2012

Yes, this guy is awesome, but don't miss his experiments in manufacturing aerogel.
posted by j03 at 9:59 PM on September 24, 2012

I tried to carbonate tea as a kid....HOT TEA! (with milk and sugar)

made a hell of a mess

hee!
posted by Homemade Interossiter at 5:27 AM on September 25, 2012