Step 4: Obtaining a Radioactive Source

There are many easily obtained inexpensive (and legal) radioactive sources available online.

See video samples / discuss radioactive sources at http://forum.nothinglabs.com

Certain years of Fiestaware dishes featured a "radioactive red" color that actually contained uranium!

A small chip can make an excellent cheap cloud chamber source - try searching ebay for "fiestaware sample"

Small Autunite samples commonly sell for about $20 on ebay (contains uranium).

Search ebay descriptions for "geiger" and "cpm" to see other possibilities.

Alternately - the cloud chamber can be used without a radiation source to view cosmic rays.  They typically appear once every 1-2 minutes.

Take precautions appropriate for your sample!  The provider of your specimen may be able to provide further information on its safety.

To be extra safe - use gloves when handling.  Wash your hands after if you should touch it.

<p>I have tec12712 and tec12710. Which order should I put them in? And what power supplies should I give them? Thank you</p>
Sorry for slow reply.<br><br>Definitely put the 12712 on the bottom. <br><br>Both those peltiers are going to try to draw a lot of current.<br><br>I would try running the bottom peltier (12712) at 10-12v - it will draw something around 8 to 12 amps at those voltages. Try to find a beefy power supply.<br><br>I'd run the top 12710 at about 3-6v. Expect 2-5 amps current draw.<br><br>Good luck!<br><br>-Rich
<p>Great, thank you:). </p>
<p>Hello, I am working on improving a cloud chamber design for Siena College. One of the questions raised is based on the performance of the peltiers. Several of the peltiers we have will measure with a higher or lower resistance than the mean. I'm trying to test their performance by taking their temperatures after a set amount of time while on a Cooler Master V8. I'm trying to do this without applying thermal paste to avoid the mess and the cost. However, without the paste, there isn't enough contact to efficiently pull heat away from the peltier. Do you have any suggestions of ways to replace the thermal paste, just for testing? We have tried tape and a weight to hold it down but the tape is not effective and a weight disrupts my ability to take measurements.</p>
Hey there - sorry for slow response...<br><br>You could try just using water or rubbing alcohol to help mate the coolers.<br><br>Im honestly not sure how useful trying to test the coolers is though. Ive had good results with various size coolers - and im not sure if the measuring variability between different coolers of same rating is going to help.<br><br>Also - not sure if cooler performance / draw will reliably map to measured resistance (ie - not sure if peltiers behave quite like resistors in regards to power consumption)<br><br>Best of luck!<br>
<p>Why did you choose to apply more thermal paste to the top peltier? Some students at Siena College had the same idea but I haven't found the necessity. As long as you have an even application, less thermal paste works. Thoughts?</p>
you are correct - you should use as little thermal past as possible while assuring good contact between the layers (I was probably being a bit sloppy)
<p>Hey, there are only TEC 12712 available in my local hardware store. Is it possible to do this project with two of those?</p>
You -might- get those working if you run the top cooler at a lower enough voltage (maybe 3v or lower). <br><br>Ultimately you'd be much better off using a smaller value peltier on top.<br><br>My advice would be to order parts closer to whats described in the project.
Hi Rich, I am currently building a cloud chamber as a physics project. I would really appreciate it if you would be willing to give me some advice/guidance.<br><br>I have read your inscrutable and that has been very helpful. However, the design of my cloud chamber is different than your inscrutable. I am currently using 6 (3 by 2) 12706 peltier coolers in a single layer. I have a water cooling system that uses a 5&quot; x 4.25&quot; x&nbsp;1.5&quot;(thick) heatsink which I made a copper enclosure for so I can pump water through it. I have a 1 gallon reservoir of ice water pumped through the water block/heatsink and then through a small radiator cooled by 3 pc fans. The chamber floor is a piece of 1/16 black garolite. The chamber dimensions are 6&quot; x 5&quot; and 4.5&quot; tall with plexiglass walls and top. I did a test today and the floor didnt get cold enough (maybe -5f measured with an ir thermometer). Without the garolite floor and just the tops of the coolers exposed, some of them got down to ~15f. I never saw a supersaturated layer though, and there was alcohol pooling on the floor of the chamber.<br><br>I am not sure exactly what needs to be improved but I think I will start with the coolers. I can get some 12710 coolers on Amazon try running 4 of them at 12v with 4 of the 12706's on top at 5v(or possibly both at 12v?). I am hoping that the chamber is not too large since that would be hard to change. Although I can make it shorter relatively easily.<br><br>What would you recommend I do? Thank you in advance for any help. If you need more information or pictures let me know.<br><br>Thanks, Ben
<p>hey benw102. i am making an cloud chamber in physics too and i found an nice tutorial for that. </p><p>shopping list:</p><p><a href="http://xionone.co.uk/howtomakeacloudchamber1.htm" rel="nofollow">http://xionone.co.uk/howtomakeacloudchamber1.htm </a></p><p>electronics:</p><p><a href="http://xionone.co.uk/howtomakeacloudchamber2.htm" rel="nofollow">http://xionone.co.uk/howtomakeacloudchamber2.htm</a></p><p>assembly:</p><p><a href="http://xionone.co.uk/howtomakeacloudchamber3.htm" rel="nofollow">http://xionone.co.uk/howtomakeacloudchamber3.htm</a></p><p>i hope this helps you<br></p>
That was helpful thanks! How is your cloud chamber coming along?
Hi Ben - sorry for slow response. <br><br>You're hitting very common challenges trying to scale this project up (I've tried a few larger builds with poor-to-mixed results).<br><br>If you're seeing alcohol pooling - but no supersaturation - I would try wiping the surface down. <br><br>I would -not- trying running 12v to the top coolers - it will generate more heat than the bottom coolers can handle - and you'll end up with less cooling.<br><br>I would definitely look at the links that LaurinS2 sent. They probably are a better source of information than myself on this.<br><br>Good luck!<br><br>-Rich
Thank you for the tips. I have done some experimentation and I am having luck using 4 10amp peltiers on the bottom at 12v and 4 9amp coolers on top at 5v. I get good results for about 20-25 minutes before my ice water heats up. I am also using a black anodized aluminum floor that seems to work about as well as duct tape over the coolers. I might try a smaller lower powered air cooled decice that can run at room temperature. Thanks again for the help!
<p>Hi Paul, I hope youre enjoying your weekend! I just had a quick question about which type of alcohol to use. Where I am currently they only sell 88% isopropyl at the pharmacy. I've tried this and also denatured alcohol form the states and I can't get a fine mist above my coil. I currently have a reading of approx -47 F using an infared thermometer so my temp is great, my only problem is that i get small drops of alcohol on my coil rather than a mist. Is there anything I can change in my setup for this to happen? I was thinking that I wasn't getting cold enough temps but after checking and freezing a drop of water on my coil I was sure it was cold enough. Any ideas? Perhaps my alcohol isn't pure enough? Could I perhaps use grain alcohol (everclear etc..) to get a fine mist? Any help would be greatly appreciated. Cheers! </p>
I use 99% isopropyl - but have used 90% with good luck.<br><br>If you can't find high grade isopropyl in the pharmacy - you may want to try an autoparts store. &quot;Isoheat&quot; is a gas treatment that's mostly isopropyl alcohol I've had good luck with.<br><br>-47f should be plenty cold.<br><br>I'm assuming your coil is for HV? I've seen too much HV hurt performance. I'd try starting off just using a balloon for static.<br><br>Too much alcohol can also be a problem. If your getting lots of mist but no tracks - I'd try less.<br><br>Hope this helps!<br><br>-Rich
<p>Rich, I like the idea of this project for a STEM and class demonstration, but I have to ask a simple question. I have both fiesta-wear, but would really like to use my collection of button sources. Do you think using higher rated sources, such as Cs-137 or Co-60 1 - 100 micro-curie sources, saturate the given construction?</p>
Hey there - sorry for slow response..<br><br>Yes - I suspect those sources may overload the chamber - but there's an easy solution....<br><br>I'd just put the sources outside / near the chamber. You probably won't see any alpha - but should see beta / the effects of gamma.<br><br>Good luck!
<p>Hi, I have built a cloud chamber into an insulated wall clock with a perspex outer clock face/ surface. My query is in regards to the static component; The perspex face retains an ample static charge within the material itself and the chamber is approx. 4cm deep. Is this sufficient (with occasional recharging) to keep the atmosphere clear of dust and ions for better ion trails within the super saturated alcohol layer or will I need to implement another feature for this application? I have never been clear on the static component of this chamber and wish to avail of your expertise! </p><p>Also, is there any source (other than the Ebay connection) that sells the 12710 168W Peltier cooler modules?</p>
Hi Paul. I've always found the static element of cloud Chambers to be somewhat black magic. I know some people had good luck implementing high voltage sources although I've always favored periodic use of a balloon rubbed over hair or fabric - mainly due to the simplicity.<br><br>For more info on high voltage sources you may want to look up information on wilsonian cloud chambers online.<br><br>I don't have a specific source of single stage pelier coolers is that I favor. For dual stage peltier coolers I've always had good luck with custom thermoelectric as mentioned in the instructable.<br><br>My general advice on finding shelter foolers is to try to be flexible - a 12010, 1209 or 12708 can work for the top stage the key thing is using a lower value for the bottom of page. Coolers may also be listed by their wattage / amperage at given voltage as opposed to the typical numbering scheme. The key thing is to dig into the specs little and try to get a sense of what you're getting. <br><br>Good luck!<br><br>
<p>I saw a post on youtube in which a cloud chamber static charge is built up using an electric bug swatter. Create a screen grid inside your chamber above the cooler. Run the ground to the bottom cooler plate and you'll get a few thousand static volts every time you push the button.</p>
<p>Good day and thank you for these great plans. I'm running into my coolers not getting cold enough and I'm wondering if it's my cooling system. I'm using a water cooled system that seems to be working well, but the water does eventually get warm (45C) after 10-15mins. Perhaps this is not sufficient? I've got a 400w ATX supply with 5v and 12v setup correctly. Any help would be appreciated. Thanks!</p>
Hi there! Yes - it sounds like your cooling system isn't quite keeping up. It's hard for me to offer any scientific insight as there's a lot of variables involved. However - I will say that modern CPU coolers with heat pipes are profoundly effective at getting heat off of a surface.<br><br>I've played with some homemade water cooling approaches and have found it hard to get good performance.<br><br> One thing you might try is either I clean the water out with fresh tap water to keep the temperature down or alternately try adding some ice cubes to see if that helps.<br><br>Good luck!
<p>I built one following the directions exactly, and I'm having the same issue, I can only get the temp down to -7C. My water cooling is definitely working as it starts to get warm after a few minutes, but I wonder what you mean by it may not be keeping up. Is there a way to test that it's not keeping up? </p><p>I've looked at the datasheets for the peltier coolers and they say that the 12710 runs at 15-17 Volts, and the 12709 runs at 15 Volts. </p><p>With the top peltier running at 5V and 2.5 Amps, the power consumption is only 12.5 Watts, compared to its max of 138 Watts. Could this be the problem that I need to fix, or am I missing somthing? </p><p>Thanks for your help!!</p>
So - cheap cpu coolers using heatpipes are very efficient. My main advice is to try a cpu cooler as described in instructions before trying any homebrew cooling approaches.<br><br>Good luck!<br><br>-Rich
<p>Thank you for the information Rich. I agree that the aluminium cooler block heat sink isnt big enough to remove a sufficient amount of heat from the cooler which is why I'm not getting low enough temps. Maybe a cooler block thats 2-2.5 inches thick might be able to maintain a lower temp, or perhaps more flow from a second pump might move enough heat, but at that point a copper cooler sink is much more practical. Thanks again!</p>
<p>I made a video of a temperature test I carried out :)</p><p><iframe allowfullscreen="" frameborder="0" height="281" src="//www.youtube.com/embed/z4Wn9hzjm-w" width="500"></iframe></p>
<p>Hi!</p><p>Is it possible to use something like this Static Electricity Generator for clearing the ions? <a href="http://www.instructables.com/id/Make-a-Static-Electricity-Generator-Cast-Lightning/" rel="nofollow">http://www.instructables.com/id/Make-a-Static-Elec...</a></p><p>Also, thank you for these instructions! Still waiting for my Peltier elements from China but as soon as they arrive I'll get to work! :)</p>
<p>I suspect that might work! I've played around with HV a little - if you don't get good results - wait a bit / and or reduce the voltage.</p><p>Good luck with build!</p>
<p>Why two separate power supply for peltier and fan while both can run in 12 V ??</p>
<p>Hello</p><p>I've read the various comments - the solutions are simple</p><p>Develop a kit - under 200.00 - add some free tech assistance - I'll buy two</p><p>One for home - one for office - makes a great conversational piece.</p><p>Have a good presentation - easy to assembly kit - go to work </p><p>I'm waiting to buy one now - </p>
<p>Hi Rich,</p><p>I finished building mine and I get a good supersaturated layer over a 5x5&quot; black anodized aluminium plate. I suspect the chamber is working well since I get really good &quot;fake trails&quot; whenever I place/remove/recharge my static source (balloon). however, I don't seem to get trails coming from cosmic rays. Is there a trick with the static source regarding cosmic rays?</p>
Hi Thomas -<br><br>It's most likely you aren't actually getting cold enough to see traces.<br><br>From my experience - the kind of &quot;ghost trails&quot; that occur when moving the static source around can occur at higher temperatures than needed to see traces from particles. <br><br>The peltier setup for this project has fairly modest cooling power - and can really only cool a small area down to the -15f or so needed to see traces. <br><br>Using thin plastic for a surface causes a small area to be cooled directly above the peltier (due to low thermal conductivity). Using aluminum will attempt to cool a larger area - and will counter-inuitively produce less cooling.<br><br>I had some luck extending the saturation area with an aluminum base-plate - but only using much larger peltiers - and insulating the bottom of the plate.<br><br>My general advice to anyone trying this project is to start with a thin plastic base-plate - get that working - and then experiment from there.<br><br>Good luck!<br><br>-Rich
<p>Rich, you were absolutely right !</p><p>I removed the aluminium plate and used a thin transparent plastic sheet blackened from under with a sharpie. After a few minutes of cooling, I reached between -45F to -50F (compared to -10F previously). I can now see about 5 to 10 trails per seconds above the peltier area.</p><p>Thanks for the advice !</p><p>Thomas</p>
<p>glad it's working for you. now for some real fun - go get some uranium ore on ebay!</p><p>-Rich</p>
<p>Wow! I love your detailed instructions! I also like how you used easy-to-find Peltier coolers instead of difficult-to-acquire dry ice. Hopefully I can try this out soon!</p>
<p>mine gets cold on the upper side, but how can i know that the connection to heatsink is ok? i used kinda less grease ! im worreid that overtime it will get hot ! or my thermal connection is not good :|</p>
If things work (ie - you can see traces) then you're getting good contact.<br><br>Other way to test is to use an infrared or contact thermometer that can go down to -20f or colder. <br><br>In general - less grease is better assuming you get full coverage.<br><br>Good luck!<br><br>-Rich
<p>I have a dumb question about powering the CPU fan. I bought the Cooler Master Hyper 212 for my chamber, which has a 4pin output. I tried looking up which pins to connect to my 12V 8A power supply, but I can't seem to get a straight answer online. Did anyone else use this fan that can help me out?</p>
<p>It's been a while - but I believe this is correct:</p><p><a href="http://www.pavouk.org/hw/fan/en_fan4wire.html" rel="nofollow">http://www.pavouk.org/hw/fan/en_fan4wire.html</a></p><p>short answer - black = gnd, yellow = 12v</p>
So I've constructed a cloud chamber using this article and have run into a slight problem. Everything works but I don't think the chamber is getting cold enough. I haven't had a chance to buy a thermometer yet but I'm fairly certain it will only confirm what I think I know. The alcohol is condensing on top of the cooler forming a thin square layer to form on the base, but no mist at all. The voltages are 12 for the bottom and 5.6 for the top cooler, so are there any other things I might need to adjust? I have already removed and reapplied some arctic silver but no dice. There is a good amount of frost buildup underneath the container by the coolers so maybe the container is too thick? I bought one similar to the one used here however. Any troubleshooting advice would be greatly appreciated!
Sorry for taking so long to reply. <br> <br>What kind of light are you using? (LED light is pretty much mandatory to see the traces) <br> <br>Also - have you painted / used a magic marker to make the surface black? That's also critical to see anything. <br> <br>The exact container I used seemed almost custom-made for cloud chamber user with it's thin bottom. It's definitely possible the one your trying is too thick at the base. <br> <br>One option is to use some thin black plastic (1/16th&quot; or so is best) for the chamber base - and then use a water glass for the chamber itself (don't worry too much if the seal isn't totally perfect). This is the approach I usually use on chambers now. <br> <br>A local plastics retailer might have something that would work. Can also try something like a plastic picnic plate. Either way - paint or magic-marker it black. <br> <br>The alcohol pool itself will inhibit traces - so if it forms - wipe it off with a paper towel. <br> <br>Hope this helps! <br> <br>-Rich
I am going the route using the single dual stage peltier cooler you listed. I bought a 12V 6A 72W power supply for it. Just a stan dard AC DC transformer. I am worried about the Power rating on it. Should it be enough for the peltier. It will be used to power the TEC only. I am experienced with electronics but I have not worked with TECs much at all.Thanks for the help in advance!
what kind of plastic do you use on your commercial chamber? id like to know the thickness too. the plastics i have used are about an 1/8th of an inch thick but i think it has insulating properties. if you don't mind me asking,i know your trying to sell them.
i don't really keep a lot of secrets any more - happy to share. <br><br>I use 1/16&quot; delrin plastic (check mcmaster.com) in the commercial cloud chamber. delrin is a bit flexy though - so I support it with some thicker plastic around the edge. <br><br>my suggestion for others would be to use 1/16th&quot; garolite. mcmaster.com had this in nice 6&quot;x6&quot; pieces in black last i checked. <br><br>I like garolite because it's stiffer than most plastic. iif the material is too flexible - the temperature differential will cause major flex that can be a problem. <br><br>for any kind of plastic I recommend getting black if possible to avoid having to paint it. <br><br>I wouldnt worry too much about how insulating the plastic is.
i have a problem. im not getting a fine mist but the alcohol is pooling over the peltier. i have abandoned my aluminum plate for now and am using a Tupperware container <br>
do you have a temperature reading?<br><br>Is the surface black? It's pretty much impossible to see the traces / mist against a light background.<br><br>What kind of light are you using? If you are using something other than an LED - probably won't work.<br><br>Good luck,<br><br>-Rich
what about something like this... The peltier would fit in the square hole. then the aluminum plate would mount to the cpu cooler. insulation would fit between the peltier and the plate. a square plate would fit over the pelteir to protect it from the alchohol
Maybe? Couldn 't really say for sure.<br><br>My suspicion is that you'd only get super-saturation (trace visibility) over the actual peltier.<br><br>Might want to try getting everything working with a plastic sheet first - then experiment - but good luck with whatever path you try!<br><br>-Rich

About This Instructable




Bio: Hi, I'm Rich Olson (nothinglabs.com). I sell cloud chambers for viewing radiation, make robots and dev software. If you need something prototyped - I ... More »
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