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Lava Lamp Centrifuge
- hga 17y agoExtremely cool: "The centrifuge is a genuinely terrifying device. The lights dim when it is switched on. A strong wind is produced as the centrifuge induces a cyclone in the room. The smell of boiling insulation emanates from the overloaded 25 amp cables. If not perfectly adjusted and lubricated, it will shred the teeth off solid brass gears in under a second. Runs were conducted from the relative safety of the next room while peeking through a crack in the door." Read the rest to learn if a lava lamp will work on Jupiter or during a space shuttle launch (2.3 or 3 Gs).
- jayair 17y agoLoved the "Runs were conducted from the relative safety of the next room while peeking through a crack in the door.". Thats the (Tesla) spirit!
- hga 17y agoYeah, a serious centrifuge demands respect. Back when I was in high school I did a bit of biology research one summer. My lab's ultracentrifuge had a lid which was solid 3/8 to 1/2 inch steel plate. Working the lever to slide it to the side was a good reminder to ask the question "Are you sure you've properly balanced these (nitrocellulose) test tubes?"
- mikepurvis 17y agoMy team's washing machine prototype achieves 200+ Gs in the spin cycle. There are some problems in this video that have since been corrected, but check it out: http://www.youtube.com/watch?v=mK2vpqXk8Jc http://www.youtube.com/watch?v=mK2vpqXk8Jc
- rbanffy 17y agoGood. You can then test if a lava lamp would work on a neutron star.
- Groxx 17y agohaha, that's awesome. Is there a goal to this project aside from epic-spin-dry? I'd love to see where it's headed.
- mikepurvis 17y agoIt loads through the side of the drum, rather than the end—this addresses two major mechanical sore-spots in traditional front-load washers (which are otherwise vastly superior to top loaders). It's not an entirely new concept (cf. http://www.staber.com/ http://www.staber.com/), but our approach to the door and very ingenious and novel.
- johnohara 17y agoNo wonder landlords ask for a security deposit.
- dasil003 17y agoUpon clicking the AVI video links in Safari I discovered that the QuickTime logo is strangely reminiscent of a centrifuge. http://skitch.com/dasil003/n292m/http-neil.fraser.name-hardware-centrifuge-3g-payload.avi http://skitch.com/dasil003/n292m/http-neil.fraser.name-hardw...
- ars 17y agoIf you plan to make one, make the radius smaller, but the velocity higher. The energy stored in this goes by the radius squared. But the centripetal force on the object at the end goes by the radius. So a smaller faster one is less dangerous, and also requires a less powerful motor (or the motor you have can give you a higher force). Although the bearings are probably a bit harder to handle when it's faster, the whole thing will weigh less. On the con side, a smaller one will have a larger difference in force between the top and bottom of the lava lamp, making your experiment less accurate.
- westbywest 17y agoFaster RPM also increases velocity of would-be shrapnel. Either you prepare for the risk of a slowly-rotating, large rotor/axis assembly failing catastrophically, or a faster-rotating, smaller assembly shedding poorly-fastened bits from the ends of its rotor.
- ars 17y agoActually no. The velocity of the shrapnel tracks the energy stored in the device. Meaning a larger radius has faster shrapnel. Note: velocity as used in my earlier message is circular velocity, (AKA RPM), not linear velocity.
- rbanffy 17y agoThe velocity of the shrapnel is the same as the linear velocity of the part it detached from. If it detaches from a faster moving surface, it will fly faster.
- westbywest 17y agoSorry for fudging may response with a term for angular velocity, instead of linear velocity. I was writing from the assumption that the primary point of a smaller centrifuge would be to safely get higher centrifugal forces at the ends of the rotor, which would require that the ends of the shorter rotor move at greater linear velocity.
- 17y ago
- arethuza 17y agoI want to see the videos of the failure mode testing :-)
- Groxx 17y agoI love that the "data recorders" are a cell phone and a camera. This is awesome. Everybody should do something this awesome in their lifetime. edit: Yikes, anyone got a torrent / mirror for those videos? They're crawling at sub-30kbps for me.
- Groxx 17y agoWell, if anyone's interested, these links should work in a bit over an hour (or two... fluctuating speed), provided it all downloaded correctly (I'm headed to sleep). Don't try before then, they won't be complete, I'm just downloading to my Dropbox. http://dl.dropbox.com/u/363028/temporary/3g-side.3gp http://dl.dropbox.com/u/363028/temporary/3g-side.3gp (16mb) http://dl.dropbox.com/u/363028/temporary/3g-floor.avi http://dl.dropbox.com/u/363028/temporary/3g-floor.avi (159mb) http://dl.dropbox.com/u/363028/temporary/3g-payload.avi http://dl.dropbox.com/u/363028/temporary/3g-payload.avi (43mb) Please mirror / set up a torrent if you can, I'd prefer to not nail my Dropbox too hard. (payload is interesting, you can see the twisting caused by the spinning)
- deleted 17y ago[deleted]
- pinstriped_dude 17y agoThe music is cool and the "study" room setup is endearing. But, in plain English, what's the result of the experiment ?!
- brisance 17y ago"As one can see in the video above, the lava lamp continues to operate well at three times the force of gravity."
- Groxx 17y agoAs well as "IT LIIIIIIIVES!!!!" when you get it spinning for the first time, and scaring / awesome-ing the neighbor kids. What the heck is that thing made of, anyway? An erector set? Juice bottles? Over-powered wires and motors? That beast is worthy of a Frankenstein moment.
- froo 17y ago>That beast is worthy of a Frankenstein moment. I agree, who's spirit can only be really captured by a large toggle switch mounted on the wall that you have to flip which dims the lights as it happens.
- ars 17y agoIt's made of http://en.wikipedia.org/wiki/Meccano http://en.wikipedia.org/wiki/Meccano
- Groxx 17y agoSo, pretty much yeah, an erector set, though possibly a bit stronger. It's not old-school erector, though. Looks like Meccano has been making Erector sets since about 1990.
- flipbrad 17y agocould an engineer/physicist be kind enough to calculate how hard that lamp would have hit the nice wall, door or window had things gone a little awry?
- eru 17y agoIf you neglect friction, you only need geometry to figure it out.
- ars 17y agoHe says it has a diameter of 3 meters, and spins at 42 RPM. (And I hope he didn't confuse diameter and radius.) So the circumference is 9.5 meters, times 42 per minute = 395.6 meters per minute = 14.76 mph or 23.75 km/h http://www.wolframalpha.com/input/?i=3+meters+*+Pi+*+42%2Fminute http://www.wolframalpha.com/input/?i=3+meters+*+Pi+*+42%2Fmi...
- pook 17y agoI wouldn't be concerned so much with glass shrapnel, as with almost molten wax spraying out. Have you ever opened up a lava lamp? The bottle is capped with an old-fashioned pull-off bottle cap. I guarantee that if anything goes pearshaped, it'll be the integrity of that cap.
- bluedanieru 17y agoWell, that's one less thing to worry about.