Make some supersaturated vapour in your living room
What we want is some substance that can be in this state, reasonably near the conditions of a living room. Almost all of the sources I’ve stumbled upon use ethanol. Cheap and available. Unfortunately, it requires temperatures below a rough -35°C.
Cooling
-35° is pretty cold. DIY-sciencists from the Web often use dry ice, because of its so-called high availability, especially in the month of october. This isn’t true all the time outside the USA. Moreover, when all your dry ice has turned to gas, you lose all the cool.
This site was the first I crawled where they used peltier modules to cool our alcohol. They create a temperature difference (Δ) between the two sides. Keep the ‘hot’ side at a temperature T°C, and it’ll pump juice to try to keep the ‘cold’ side at (T-Δ)°C. Two of them stacked are reported to work fine. They are made in china and I could buy 4 TEC-12710 for ~20€, and have a convenient size: roughly the bottom of a CPU heatsink.
Air-tight box
Since the cold area is going to be small, supersaturation will happen very close to the cold plate described earlier. Air inside needs to be able to set.
I’ve decided to build my own PVC box, which happened to be a very bad idea, and just glue-gun everything that didn’t need to move to make an air-tight enclosure.
High energy particle source
A radioactive source will do. α and β decays qualify. My source is americium 241
americium-241 salvaged from a smoke detector (search for an ionization chamber smoke detector on ebay). Try to stay away from very cheap models from china that can be wrongly advertised as using a ionization chamber (I’m looking at you SS-168 from dealextreme ). I got mine off a UK based store on ebay for ~15€. It’s a small, cheap and reliable α radiation source. If you’ve watched the beer cup video from earlier, you know some of that kind of particles actually travel our space all the time. They are free, but happen less frequently, always randomly, and usually create fainter clouds.
Power supply and casing
The peltier modules can use as much as 9 amps under 12V, so we need a pretty strong power supply. I’ve already decided to use a CPU heatsink, so let’s just salvage an old ATX case with a cheap supply, and fit everything there.
Proper lighting
The fleeting clouds will be dim. The only way to make them stand out, is to light your box from behind, with a very horizontal stream of light. I use one of these.
Assemble stuff together
The pictures are pretty self-explanatory.
First find an old case (can be found on the pavement)
Remove everything we don’t need. This means everything that’s not a PSU, a heatsink. Also get rid of and half the case.
Add some shoring, and screw the heatsink where there’s room
Add the two peltier modules “hot side down”, with some thermal grease between them and the heatsink (toothpaste can work for some first tests, but tends to dry too quickly).
Here is the setup in operating mode.
1 - Cold plate, where stuff happens - 2 - Plexiglas box. With sponge and bolt. - 3 - Radioactive source. Scavenged from a smoke detector - 4 - Some high voltage (here, ~250V) - 5 - PSU - 6 - Peltier modules wires
## Starting it up
Open the box, and pour some alcohol on the sponge. I’ve successfully used 90% alcohol from the drugstore. I usually pour enough so it’ll start to drip. Add your radioactive source if you got one. Alpha particles can’t travel so far through the air, so put it close to the cold plate.
Wire it all up. Top peltier plate should be connected to the 5V rail, and the bottom one to a 12V rail. A quick test showed the 2 modules stack wouldn’t be able to cool down the metal plate enough if both are connected to two 12V rails. I guess it’s because the bottom one can’t transfer the heat from the top one quick enough. Also it’s handy to have them use just one molex plug. Don’t forget to connect the fan of the heatsink.
Applying some strong electric field is optional but recommend). I mean it’s recommended to have live highvoltage wire running around in an alcohol supersaturated environment, that’s all. I’ve used a simple ~400V generator that I hacked into the PSU. I also added a switch. You can also just use any kind of staticly charged thing, like a plastic cup. I have yet to play with different voltages.
Caulk every hole, and wait a few minutes for the gases inside the box to set.
Boot it all up ! The heatsink fan should start, and you should be able to see tiny droplets of alcohol gathering on the top of the plate.
Set your light source so it’s leveled with the cold plate, and illuminating from behind.
Be amazed. Or disappointed.
Future research & TODOs
Check whether vodka is a good replacement for 90% alcohol. (spoiler: it isn’t)
Play with high voltage field inside the box. I’ve noticed that applying some voltage field inside makes the clouds thicker. I could also instanly make a fleeting cloud by approaching a charged plastic ruler near the top bolt.
Get some strong magnets to also have a strong magnetic field for the charged particles to play with.
Use led-strips for a nice lighting from every sides.
Make a smaller transparent box, made of glass to prevent scratches.
Use different sources for ionizing radiation.
Be a little more scientific, as in “more formulas and graphs”
Now how cool does that title sound? Damn cool. The crave for radioactive coolness really started when I watched this video (cloud chamber starts at 9m00s) :
If you’ve never watched any of this channel video, I urge you to go check it and meet Martyn Poliakoff.
A quick search in Youtube for information about cloud chambers will show you how ridiculously easy they are to build.
This one is even using a beer cup, which really began to make my ghetto-tech sense tingling. I had to make one.
How it works
More precisely, how I would explain how it works to someone that won’t just read wikipedia, and who I’m sure that someone won’t be able to point out how wrong I am.
Some vapour is in a state where small perturbation can turn it into liquid (supersaturated ).
Particles (or rays) with enough energy (like, going at at blazing speeds, thousands of km/h) can change the number of electrons on a whole bunch of atoms in the vapor.
That change is enough perturbation, that they leave tiny clouds of condensed vapor in their path.
Tiny cloud disappear, by evaporation and mostly just falling down.
Looks simple. It is quite simple, but a few technical difficulties had to be dealt with. More details of the renzotech to follow in another post.
I have a program (vanilla minecraft server) running in console mode which reads commands from stdin. Unfortunately it doesn’t come with all the nice things you usually want in a shell-like environment : mainly history and tab-completion.
That’s why I was looking for a way to wrap it in some script that would harness the power of libreadline for my own comfort.
I wanted to have something very simple and customizable. This way I can add my own commands and whatnots. If I got to get my hands in it, it better be in Ruby, because that’s the only language I’m efficient in (as in ‘I can write stuff without having to read documentation every two symbols’).
This is important because there is already something in C to do that there. But C requires too much thinking. I want to be able to hit the keyboard with my forehead repeatedly and expect the resulting code to work.
Fortunately this time, Ruby comes with its own libreadline bindings. This website even displays a nice tutorial, but I couldn’t find any simple example on the Web showing me how to use it to wrap another process, and especially display its output without messing up Readline stuff.
This is why I write this post, because I couldn’t understand why no one else before had the same problem as I do, and shared it to the world. I got mad, ranted, ran around waving my arms yelling in despair: “FUCK! I’m gonna have to do some work myself”. Life is so fucking hard.
So here comes the dirty code, half stolen from Joseph Pecoraro’s tutorial :
# Here goes the list of words# you want to be able to use completion on$LIST=['help','kick','ban','pardon','ban-ip','pardon-ip','op','deop','tp','give','tell','stop','save-all','save-off','save-on','list','say','time'].sort$PROMPT="> "# common promptcomp=proc{|s|$LIST.grep(/^#{Regexp.escape(s)}/)}Readline.completion_append_character=" "Readline.completion_proc=comp$stdout.sync=true# $COMMAND will be the command-line program# to wrap and its args$io=IO.popen($COMMAND,"w+")# Reading processThread.new(){whiletruesleep0.1# every time the wrapped# process wants to talk whilea=$io.gets()# save what the user was writingbuf=Readline.line_buffer# clear the current prompt and stuff$stdout.print"\b\b"*(buf.size+$PROMPT.size)# display the wrapped process outputprinta# restore the promptprint("#{$PROMPT}#{buf}")endend}loopdo# Let's summon some readline magicline=Readline::readline($PROMPT)caselinewhen/^\s*$/# We don't store empty lines in the History,# but we still want to send them # to the wrapped process. # Maybe that's something you don't want to do$io.puts(line)elseReadline::HISTORY.push(line)$io.puts(line)endend
This code won’t work with Ruby < 1.9, because Readline.line_buffer doesn’t exist there. For 1.8.x you can use Luis Lavena’s full ruby implementation of readline here.
Also it hasn’t been fully tested, it may not work at all, break everything on your system, dig some obsidian stone and suck you into the Nether or whatever. I won’t be held responsible.
Since I live in a tiny apartment and don’t want to waste too much money and time into it, I’ve decided to begin the easy way. So I just bought a “beer kit”, which is some kind of beer syrup, to pour in a large bucket with water and yeast.
I’m not going to explain anything about the brewing yet, because I’ll try to post here “regularly” about the process in progress. The whole stuff required looks like this (sorry if I was too lazy to show up every item correctly) :
The process is actually going to be quite tedious to come up with in the first place. The manual joined with the hardware is a page and a half long, with mainly badly photocopied pages with pictures, and the one that comes with the syrup is 10 lines in a tiny piece of paper tucked under the white cap of the big can.
As for the two syrup cans, here is what the brand’s website says about them:
Ambiorix : A copper colored summer beer with a light sourness but with a sweet aftertaste ;
Triple : A heavenly abbey beer: gold colored, soft but strong with a full malty flavor. Slightly spiced and well hopped.
This is going to be all for today, but just before you depart, dear reader, could you give me ideas in the comments as to which beer I should start with?
