What is the difference of a taser to a stun gun?

I think people would easily say the difference is that a taser shoot projectiles and shock them. I dont think that is it. I heard the difference is that a stun gun is a "pain complaince weapon" and that a taser is a "immobilizing weapon". Stun gun hurts and tasers make you immobilized. How does a taser achieve that? It shoots 2 projectiles and the body acts like a condutor trying to pass that current. If you use a stun gun the 2 electrodes are too close so the current need to pass only a small amount of your body. That is what I think, can anyone confirm that? I think that is why it only hurts. What if I took a stun gun and made the electodes to be very far apart?  Like take two wire and make a person hold in each hand a wire, then I would turn the stun gun on.  Would that work like a taser? So the current passes the whole body and not only a tiny spot. I hope it makes sense to someone. Thank you

Topic by a408228   |  last reply

magnetic ball bearings

How do  magnetize my own ball bearings for making magnetized Fullerine geometry? Sorry cant find the right word for it, i'm obviously scientificaly challenged.

Topic by craftyv   |  last reply

Lockheed Hybrid Blimp

Looks like it gets some lift from forward motion, some from propellers, and some from buoyancy.

Topic by ewilhelm   |  last reply

Toggle between front and rear view cameras on one display in car?

I installed a front and rear view camera in my car, have a display that only accepts 1 RCA input, and want to be able to toggle between the two video feeds.  I've seen pictures of other people that have done this with what appears to be a simple toggle switch but I can't find any wiring diagrams/instructions.  Can anyone shine some light on this for me and explain how to do it? 

Topic by mrwd40   |  last reply

The Christmas Special 2010. [Paper airplane]

In this special, you will make a paper airplane that are: Tough Water Proof Ice Proof Snow Proof Mud Proof Made out of Foil Strong A glider Fire Proof [Option] paper airplane. To enter this, just put a picture of it outside in the snow or inside and put some bit of comment about it as well also put your paper airplane instrutable web address. Make sure it's flys, glides and works for lasting months or more!

Topic by wat. 

Watch engineers build a Mars rover!

This is super-cool. NASA's JPL has set up live streaming video from inside the clean room where they're building the Curiosity rover, formerly known as the Mars Science Laboratory. Work is from 8am-11pm PDT Monday through Friday. I found this on Saturday morning and I've been waiting all weekend for those slacker engineers to get to work so this would be worth posting. Some comparison: The old Sojourner rover from 1997 was the size of a largeish R/C car. The Mars Exploration Rovers from 2004 that are still running (!) are the size of golf carts. This thing's the size of a Mini Cooper, and has a proportionally larger load of sciencey stuff packed on. Instructables doesn't allow you to embed Ustream into Forum topics, so you'll have to go to Ustream to watch: http://www.ustream.tv/nasajpl Via Bad Astronomy Blog, image from MSL website

Topic by CameronSS   |  last reply

I'm looking forward to Kelseymh's next Instructable...

"How to Make a Universe" I'm making space in my shed this very weekend...

Topic by Kiteman   |  last reply

Electromagnetic induction questions.

OK, this is another one of those questions I should know, but don't.  Mainly because I have never done it before, I have a whim to build an electromagnetic launcher, something table-mounted with a range of around 3-5m (10-15 feet).  I'm not after launching nails through Coke cans. I have been browsing the web, and the designs all seem to be much more complicated than is really necessary for toy. The image below is a scan of my badly-drawn thoughts of how simple it should be. Have I got that right? I plan to use a bunch of capacitors harvested from dead electronics and connected in parallel.  Is there a recommended total capacitance for such a device? If launching a ring, must the ring slide over the ferrous core, or would there be enough umph to launch a ring balanced just past the end of the core?

Topic by Kiteman   |  last reply

Pics of my ZipZap

Here are some pics of my SMOKIN HOT ZipZap!!!!!!!! (sorry about the somewhat blurry pics, my camera is old)

Topic by nerfer192   |  last reply

Pedal-Powered Blimp to Cross English Channel

Over in England, plans are afoot to cross the English Channel in a pedal-powered blimp. The semi-recumbent bike will power two propellers and French pilot Stephane Rousson hopes to complete the trip in five hours. Looking forward to hearing the results. Linkvia Treehugger

Topic by fungus amungus   |  last reply

Biofuel powered water pump, no moving parts and modular!

I just added a video about how to make one. http://blip.tv/file/4142099 It is probably not what you are expecting. I made the prototype and it works. Brian

Topic by gaiatechnician   |  last reply

CoilGun science project

Ok, i'm doing a science project and I chose to use the Coilgun-Handgun Instructable to build a coilgun and test its damage and lethality on human flesh using a piece of ballastic gelatin. Does anybody know if there is a way to measure the damage against the gelatin or another experiment i could do with the gun?

Topic by renkun67   |  last reply

Tripping a Breaker

Hello. I need help with charging a capacitor bank I have. It consists of 10 capacitors: 4 4700uf capacitors and 6 6800uf capacitors. All are wired in parallel. I have been charging them with 110AC rectified to DC. The only problem is that whenever I flip the switch to start charging, it trips our shop's 20A breaker and you have to flip it back to start charging again. It trips our breaker every time and dims the lights making my dad angry. So I need some tips on what wattage resistor i need to use to keep from tripping the breaker. I experimented with a 10W resistor and that was way too much resistance. I am not allowed to experiment anymore until someone credible can tell me what to do. Thanks for your help.

Topic by tinstructable   |  last reply

Advice on A centrifugal pump.

Hello, I recently was given a pet from a friend and after doing some research on what the little guy needs I came to the understanding that the current enclosure he is in is inadequate for his needs. Therefore, I wanted to save up some cash to get him the right size tank set up that I know he deserves. In the meantime though, I have plenty of things laying around the house that I feel could render him a more comfortable habitat till that investment goes through. After more research on the matter, I came to find that for most household aquariums, the bulk of the work falls on your filtration system. That being said, I wanted to go for a Wet / Dry Sump Filter setup as it would be  the most easiest system to setup at home with the various resources laying about. Unfortunately while gravity will be doing the work of siphoning the water from the tank down to the Wet / Dry Filter Media, it will not be moving it back up to the tank. For that I concluded there was no escaping the need of a pump in some shape or form to move that cleaner water back into the tank. From what I read the pump will pretty much determine how big I can make his tank.  So this brings me to my current dilemma. Presented with various motors around the house, I went for the biggest I could find (* excluding the water pumps in our cars mind you). That so happen to be a 1.25 HP Wet & Dry Shop vac that was collecting dust in the garage. I confirmed the motor is working and already came with the impeller attached to it. I was hoping to see if you fine folks could share some wisdom on how I can: 1.) Make it Waterproof. 2.) Adhere the right type of casing around the Impeller and Motor so as to benefit from the  Bernoulli's principle and get the most water moving through my system.  3.) I intend to have this setup not 15~20 feet from where I sleep, this motor is LOUD. I was reading online about creating a sound damping box for it and was wondering what suggestions you guys might have for that? I keep fearing there won't be enough ventilation and it will over heat. ....anything else you would like to throw in. TL;DR : 

Topic by Rensouken   |  last reply

Frozen Soap Bubbles

Some clever person figured out that if you give soap bubbles enough time to fall to ground on a very cold night, by the time they reach it they will be frozen. Of course, pictures have ensued. Check them out as they are quite beautifulThanks Boing Boing!

Topic by randofo   |  last reply

Ripstik/Waveboard at skatepark

How many of you have tried bringing your ripstik or waveboard to a skatepark? If not, it's really fun.

Topic by downhilldman   |  last reply

Countdown Timer

Hey guys, first forum post. I have just gotten into the electronics field, and I have made a few circuits that I have read schematics from. There's something I want to make, and it's a countdown timer. This is want I want it to have: Be able to count down from at least 15 seconds and be able to change the amount of time Have some 7 segment displays Use the least amount of voltage possible (ie: not need to use the mains or some 12 volt power supply, id rather use a couple of AA's) Have a relay capable of turning on or off a light. And to be as simple as possible. Because I am rather new to this I would rather a schematic, rather than just some help on which components I need to use, because I don't know where they need to solder to where.  Thanks

Topic by ryanlg   |  last reply

DIY Air-Powered Moped

This custom moped runs on compressed air to get you across town with no pollution and no noise. Just make sure you're not going too far as the range is only 7 miles and top speed is 18 mph.Still, a cool idea to work from. Link

Topic by fungus amungus   |  last reply

Instructable: how to make your own Buster! (members collab)

Hey dudes! lets make a collab on how to make a buster!! apport ideas! my idea is making him from an old max steel, action man, etc, burning and crashing him and putting him dummy-like stickers or paint!

Topic by santy22   |  last reply

Copenhagen or Many Worlds Interpretation?

Which interpretation of quantum physics do you prefer? Personally I favour the Many Worlds interpretation as it better explains how the particle 'chooses' what state it collapses into, whereas when I consider the Copenhagen interpretation, it makes me think that the particle is deciding, which bothers me, obviously. However, the Many Worlds interpretation throws up many issues, such as the problem of probability (if a universe is created for every possible outcome, the probability of anything is 1, including say, your computer randomly exploding now). Which is quite ridiculous. But still, to me, a better explanation. So your thoughts?

Topic by Rupert95   |  last reply

water pump

I have a very strong 18v motor from an expensive cordless drill(clutch went out). I also am in need of a pump to drive some misters, 20+ PSI. Is there a pump I can make or buy to be driven by my motor?

Topic by geckoguykc   |  last reply

The Future Of Nuclear Energy

p.MsoNormal, li.MsoNormal, div.MsoNormal { margin: 0.0in; font-size: 12.0pt; font-family: Times New Roman , serif; } p.Standard, li.Standard, div.Standard { margin: 0.0in; font-size: 12.0pt; font-family: Times New Roman , serif; } *.MsoChpDefault { font-size: 12.0pt; } *.MsoPapDefault { } div.WordSection1 { page: WordSection1; }                                              Nuclear energy is sometimes referred to as pollutant energy or “bad” energy. This is some what true but in the case of research  there is no “bad” waste being emitted from the reactions that undergo in theses reactors. Commercial Nuclear Reactors or CNRs do produce a lot of residue. They produce this residue by using their fuel so much to the point of radioactive waste. Small Research Reactors or SRRs do not do this, instead of using it up they produce new isotopes that can be useful instead of becoming waste.   So why don't we use SRRs? We do not use SRRs because of financial and safety. The safety concern comes in when the reactors are able to undergo Nuclear fission witch releases huge amounts of heat that no current materiel known to men kind is capable of withstanding. The other type of SRR is safe and financially friendly but does not produce electricity instead it uses approximately 1 million volts DC, but produces isotopes from elements such as Hydrogen witch is found in water.   In conclusion nuclear energy has not ended.

Topic by dcerin   |  last reply

And the winner is...

It's that time of year again - the Annals of Improbable Research has announced the 2010 IgNobel Prizes. It makes you proud to be British.... The full list of winners: Engineering Prize: Karina Acevedo-Whitehouse (UK) and colleagues for perfecting a method to collect whale snot, using a remote-control helicopter. Medicine Prize: Simon Rietveld (Netherlands) and colleagues for discovering that symptoms of asthma can be treated with a roller-coaster ride. Transportation Planning Prize: Toshiyuki Nakagaki (Japan) and colleagues for using slime mould to determine the optimal routes for railroad tracks. Physics Prize: Lianne Parkin (New Zealand) and colleagues for demonstrating that, on icy footpaths in wintertime, people slip and fall less often if they wear socks on the outside of their shoes. Peace Prize: Richard Stephens (UK) and colleagues for confirming the widely held belief that swearing relieves pain. Public health Prize: Manuel Barbeito (US) and colleagues for determining by experiment that microbes cling to bearded scientists. Economics Prize: Awarded to the executives and directors of Goldman Sachs, AIG, Lehman Brothers, Bear Stearns, Merrill Lynch, and Magnetar for creating and promoting new ways to invest money — ways that maximize financial gain and minimize financial risk for the world economy, or for a portion thereof. Chemistry Prize: Eric Adams (US) and colleagues for disproving the old belief that oil and water don't mix. The research, supported by BP, was published under the title: "Review of Deep Oil Spill Modeling Activity Supported by the Deep Spill JIP and Offshore Operator's Committee". Management Prize: Alessandro Pluchino (Italy) and colleagues for demonstrating mathematically that organisations would become more efficient if they promoted people at random. Biology Prize: Libiao Zhang (China) and colleagues for scientifically documenting fellatio in fruit bats.

Topic by Kiteman   |  last reply

Car light dimmer

Hi all, Can someone show me how to make a car dimmer or point me in the right direction to make one. Just to recap this is like the new cars when you open the car the light fades up and when the car door is closed the light will take 5 to 10 seconds to dim out. Thanks in advance.

Topic by Dave-v-v   |  last reply

Mythbusters Rock !!!

Don't ya think this show is awsome?It is one of my favourite shows, and is very entertaining. Some of the rigs and machines they build are amazing:e.g one of my favourite:Jamie's " Graplling Gun Ascending Winch " ( Episode- Superhero Hour )The myths are very good aswell such as "The Ice Bullet" .Im Sure you people on instructables watch this show. C'mon!What do you think of it? Fave myth? Fave rig / machine?Did any of the myths help you in life situations?( BTW, Can't wait, going to download series 4 XD)( Too bad they don't show much new episodes in England!)

Topic by Baron A   |  last reply

capacitor bank questions.

Hello all, this'd be the first post i've ever made, and may be in the wrong place....... edit- i guess it was in the wrong place, since no one replied.... so i'll try here.... i'm tryin to make a cap bank from 30+ flash cameras (possible? possible outputs? how do i calculate that?)  and i have some question/problems. is it possible to take a bank like the above and use as a spot welder?   if so, how would i trigger the spark without the trigger becoming the spark gap?  another possible use i have for it is a rail gun...... theoretically, if counter evidence isn't provided by all of you much more tech inclined ibblers a second concern is that the caps come in at least three different micro farad ratings. would one explode if it's rating is lower than the higher ones?  (the ratings are between 80ish to 150 ish (don't remember)) i rather need the weilder for a possible steampunk project that i just bought a bunch of metal junk for....(knowing me though, i'll never get around to doing it....)

Topic by badideasrus   |  last reply

Malmo says no to ridiculous car trips

Over at Grist.org Sarah Goodyear writes about an interesting approach to encouraging motorists to leave their cars at home. Malmö says no ridiculous car trips. Watch the video and read the full article here. No ridiculous car trips from Martin Lang on Vimeo.

Topic by Culturespy 

Coil Rifle (not really a rifle, no rifling)?

So, I've been considering modifying an inexpensive muzzle loader into a coil gun with a backpack power supply.... it seems to me that this would be possible but impractical, which is perfect for an art installation... I would then take it hunting, to test its lethality. any thoughts on the idea?

Topic by gschoppe   |  last reply

Solar Filter for Telescopes

Having seen some predictions of increased solar activity over the next two years, I decided to make a filter so I can check it out with my trusty telescope. To start out, I constructed the rig shown in photo A, and practiced with it by cutting disks of plain glass. Make a table like that in photo C so you can make a continuous score on the glass, without stopping. Put oil on the wheel of the grass cutter. Be sure that the surface you work on is flat. You can skip this if you want a square filter. After scoring, your glass should look like that in photo B, with a uniform and even cut. Next, put the scored glass on a soft surface like a mouse pad, with the scored surface wetted with water and face down. Press on the back of the score with a dull nail to start a crack. By continual pressing you can watch the crack propagate all the way around. Then, make 8 radial scores from the circle to the edge of the glass and propagate those cracks in the same manner as the disk. When you do it right, you get a result like photo D, where the pieces were separated for illustration. When you get good at this with regular glass, you can cut the mirror into a disk. With the mirror, you score the glass on the side that has the metal coating. Or, you can just cut the mirror in a square instead of a circle. Photo E shows an uncut and a finished cut mirror. The mirror came out of the back of a discarded projection TV. Some of the mirrors are plastic films, some are second surface, some are first surface glass but the metal coating is too thin. There are many variations, but you need to find a first surface glass mirror that reduces the light level by 12 stops (as measured by a LunaPro SBC light meter). Photographically, this is like reducing the light level from F1.4 to F64. This level of light reduction will be hard to find. WARNING: Use of a mirror with a thin reflective coating can result in eye damage if used to view the sun through a telescope. I have access to a smaller commercial filter to use as a guide. This filter produced a bright blue image of the sun, so I added a red filter at the eyepiece. This combination produced a normal yellow image of the sun. There were no significant sunspots visible, so I didn’t bother taking any pictures. The Filter is mounted to a screw-in lens cap.

Topic by ShutterBugger   |  last reply

DIY scanning tunnelling microscope

I caught this on the MAKE blog; the full article is at ChemHacker. Sacha De'Angeli has announced the release of "version 0.1" (proof of concept) for a do-it-yourself scanning tunnelling microscope. If you already know what an STM is, my work here is done. For the rest of you, a scanning tunnelling microscope moves a very fine ("single atom sharp") tip across a surface.Electrons can jump between the surface and tip, leading to a varying electric current which can be amplified and measured. How well the electrons can jump depends exponentially on the width of the gap. Near an atom is closer than between atoms, so by moving the tip in very small (nanometer) increments, you can image the atomic structure of the surface. With a less sharp tip, or coarser position control, you can still image surface structure, steps, defects, etc. UPDATE: Instructables user Fabio M had posted a different STM project last December.

Topic by kelseymh   |  last reply

lawn mower keeps dying

Bought a new 2 cycle lawn mower in the spring. It worked fine, then it starting dying. I unscrewed the gas cap screwed it back on. It worked fine for a few turns. Died again. Figured cap needed to be vented. Now it dies continuously. Need some suggestions.

Topic by sassifrasstea   |  last reply

High voltage in water increases surface tention. Why?

One day, I stuck two high voltage wires (even thought you may think this was not smart) and it made water "stick" to the ends of the wires, and it was as if there was sticky jello on top. Does anyone know why this happened and what I can do with it?

Topic by ANDY!   |  last reply

Microscope buying help?

I'm planning on buying a compound microscope and can't decide on some stuff either because  I'm a total n00b or I am a n00b. well, here they are: what eyepiece will i buy? 10 or 15x? will i buy the one with built in light or get the one with the mirror? will i get an iris style diaphragm or regular diaphragm (the one with holes) do you like pie or not? (I do) yeah, please answer in order, need answers before tuesday, 0200HRS UTC ok? thanks i'll tell you the results of what i bought after i buy it

Topic by beehard44   |  last reply

Mousetrap car Pulley help.

Hi! ive been working on a mousetrap car for my physics class and i was looking into the idea of pulleys to get more power to pull on the axle to rotate it. Ive noticed that alot of the Pulleys I see all rotate on an axle which I can not acheive due to the small space on the car. So my thought would be to anchor these small wooden pucks (small like 1 cm diameter) and have notches in them so that the fishing line wouldnt slip. (picture) Can I get some help on wether or not this would work? If it works can I get some input on how i could make it better? ex. different pulley designs that dont require moving parts. Thanks in advance!

Topic by noobiefied   |  last reply

using the acetone method , what type of container , can i make and store the melted styrofoam in?

reading a couple posts about reducing styrofoam using acetone.  i happened to come across a lot of pieces and need to reduce it, but am not ready to use it yet. what containers ahere good for this , acetone comes in metal cans, many of the instructables say to do the melting in glass, i have seen some say metal,but no specifics. i dont have a glass open top bottle handy yet, but i may if i have an idea of the ratio of plastic to expanded.  i thought i saw a video on you tube of a guy using a plastic bucket and storing it in a zip lock bag.I would need to verify that method and the type of plastic first. since  most instructables use glass and metal pots. Off to break it up

Topic by escapefromyonkers   |  last reply

DIY Shred Style

Fuel TV's show "Built To Shred" is kicking off it's third season this Sunday the 26th. Jeff King hosts and demonstrates lots of DIY know how, offering up inspiration for anyone who has ever said, "There's nowhere to skate." Worth a watch. Check out their site on Fuel TV Older episodes available on Hulu

Topic by Culturespy   |  last reply

bike charger

I ride on a bicycle patrol around my neighborhood three times a week.  (6-8 miles, good exercise) I also have another bike with a Wilderness Motor on it.  (36 V, 600 Watt motor) I don't use the Wilderness bike much anymore, but how could I wire a gizmo to charge some AA and/or AAA batteries?

Topic by rcg40   |  last reply

LED driver.

i want to make a LED light source, I have found a few on other places, but not sure of those. I have a 9v battery, 4LEDS.  If anyone would be so kind, I have two set ups I am considering. One will have a 555timer, to make the LEDS "pulse"    The other is just direct connect battery to LED i am aware a resisitor or several are needed for this direct arrainagement, so my question for this setup is how to make the most of it. a third option is to incorporate the two above.  *did find an instructable which used a wall plug as the driver, with some modification of course. thanks in advance.

Topic by mossDboss   |  last reply

Infrared spectrophotometer price

Hi I have a PU9716 Infrared Spectrophotometer and want to sell it. I am not sure what it's worth or when it was made, but I am told its in working condition. I got it for free from some people for whom it did not provide accurate enough readings. I got some info of the plate on it: serial number: 371261 part number:9423 297 16151 program number:4013 172 55513 Made in England Any help is appreciated.

Topic by dkedr   |  last reply

Possibility of "gravity chamber" becoming a reality

I used to watch the show  "Dragon Ball Z" when I was younger, on some of the episodes there was a gravity chamber which would increase the gravity in the room. It would go up to 450G (1G= 1 times the Earth's gravity) I know this is completely impossible but could a device like this even exist and if it did would make it to 2G's? Before you respond I know this is just a show and not reality. If this did work this would help athletes train and astronauts (if and when the moon is colonized)

Topic by crc09   |  last reply

Intact fog light wiring and switch going to waste, what else could they be used for?

I'm 16 and have a '83 Toyota Tercel, a bit of a junker, but I'm trying to learn everything I can from it. The previous owner removed the front turn signal assemblies and replaced them with fog lights which isn't legal to drive in MT. I bought and installed the new turn signal assemblies, and almost removed the fog light wiring (plus the switch inside the car to turn them on), but I would hate to waste all that wiring already set up nice and neat. What else could I hook up to them? Any ideas?

Topic by mojobo1   |  last reply

mission of venera

The Venera (Cyrillic: Венера) series of probes were developed by the USSR between 1961 and 1984 to gather data from Venus. As with some of the USSR's other planetary probes, the later versions were launched in pairs with a second vehicle being launched soon after the first of the pair. Ten probes from the Venera series successfully landed on Venus and transmitted data from the surface, including the two Vega program and Venera-Halley probes. In addition, thirteen Venera probes successfully transmitted data from the atmosphere of Venus. Among the other results, probes of the series became the first man-made devices to enter the atmosphere of another planet (Venera 4 on October 18, 1967), to make a soft landing on another planet (Venera 7 on December 15, 1970), to return images from the planetary surface (Venera 9 on June 8, 1975), and to perform high-resolution radar mapping studies of Venus (Venera 15 on June 2, 1983). So, the entire series could be considered as highly successful. Unfortunately the surface conditions on Venus are extreme, which meant that the probes only survived on the surface for a duration of 23 minutes (initial probes) up to about two hours (final probes). Venera is the Russian name for Venus.

Topic by Waren-Neutron   |  last reply

Solar panel mounting and tracking.

I have a new video about equatorial mount for solar panels. If equatorial mount is turned slowly at the right constant speed, then the panels point at the sun all the time. I also have a diagram about something to get that constant slow speed. I have it done this way to avoid wind damage. I think if you did it this way and had a sump pump to pump the water back up every morning the thing could be  automatic, cheap  and very accurate. Brian

Topic by gaiatechnician   |  last reply

12v car fan motor for an electric bike

Hi everyone ! I have a project for school that's called "the no project project". I have to do anything I want... so I had the idea of doing an electric bike, or tricycle. So I searched for motors... chainsaw motors... etc ! I have a little budget, and I red it was possible to use car heater fan motor, so I was very interested! But I wanted to have a confirmation from you guys... is a car heater fan motor as powerful as a wheel hub motor? and it is possible to use them as a electric bike motor? Thanks !

Topic by Antoto   |  last reply

mission of sputnik 1

Russian technology satellite. One launch, 1957.10.04. Tikhonravov's 1.4 metric ton ISZ satellite was to have been launched by the new R-7 ICBM as the Soviet Union's first satellite, during the International Geophysical Year.    But it was not ready in time, so Korolev hurriedly developed Sputnik 1 as a replacement. It became the first artificial satellite of the earth. Sputnik 1 had 1 watt of power, producing an 0.4 second duration signal on the 7 and 15 m bands. Four antennae were deployed at 35 degree angles. Power was provided by three silver-zinc batteries. Thermo-regulation was by a ventilator. The 580 mm sphere had a mass of 83 kg and was made of highly polished Aluminum AMG6T alloy 2 mm thick. It was built without drawings due to the quick time schedule. Korolev was everywhere, supervising all aspects of its construction. It functioned for 21 days.      AKA: PS-1. Gross mass: 84 kg (185 lb). First date: 1957-10-04. Number: 1 .     the word sputnik is russian word for traveller

Topic by Waren-Neutron   |  last reply

Piston jump boots

I dunno if you have ever seen this guys 'rocket boots' (not really rocket powered) but they are sort of neat. They do not get the same results as simple mechanical leaf spring sort of moon boots I see, but the concept is pretty interesting for those of us who are fans of combustibles.  this is a video http://www.youtube.com/watch?v=w7s-tnzPZ3c article http://www.technovelgy.com/ct/Science-Fiction-News-Comments.asp?NewsNum=740 Now my question: How would you improve this sort of unimpressive piston powered boot? I was thinking if one could double or even triple the chamber size of that piston, or use multiples of them, maybe use a more potent combustible than gasoline.

Topic by ThorsMitersaw 

Blasting Cap help

I was wondering what others use for their cap bodies, i have been told to use spent brass to hold the HMTD. any better suggestions?? ANFO doesnt like brass so i was wondering if AL casing or heavy paper casing would work better? Thanks.

Topic by joeskater26   |  last reply

universe expanding forever?

I saw this article on the BBC news site: http://www.bbc.co.uk/news/science-environment-11030889 which has some astronomers apparently claiming that they have now worked out the fate of the universe from measurements on distant stars magnified through a galactic cluster. The final quote is: Professor Priyamvada Natarajan of Yale University, a leading cosmologist and co-author of this study, said that the findings finally proved "exactly what the fate of the Universe will be". This seems like a pretty bold claim to me - I was thinking that even if we had a lot of such measurements then we would still only be working out the geometry of space/time in the region of our universe that we are capable of seeing. This is likely to be only a small part of the whole universe due to the galactic horizon imposed by the age of the universe against the speed of light. Also, even assuming that the whole universe of 3D space and time that we live in behaved the way they are saying, this is still only working out what would happen due to the universe's own internal dynamics - there are ideas coming out now about our universe being part of a wider multiverse outside the realm that we experience as normal space and time, so even if the universe did expand into a "cold dead wasteland", then something could possibly infringe upon it from outside space/time and make something different happen at any time in the future. Some of what's going on here is just bad journalism - there's a longer article here: http://pda.physorg.com/darkenergy-universe-magnifyinglens_news201427857.html which gives a fuller version of the same quote: "The geometry, the content and the fate of the Universe are all intricately linked," says Natarajan. "If you know two, you can deduce the third. We already have a pretty good knowledge of the Universe's mass-energy content, so if we can get a handle on its geometry then we will be able to work out exactly what the fate of the Universe will be." This is a bit more cautious but there's still this idea that by making measurements like this from just one point in space and time we can work out the fate of the whole universe, which I don't really believe. So I reckon these sort of predictions should be taken with a massive pinch of salt, rather than definite statements of what we know. Which may be obvious, but I wanted to say it and see what anyone else thinks?

Topic by ganglion   |  last reply

1 watt Frequency Doubled Violet Laser

I want to make a 1 watt violet laser, by using a 1 watt 808 nm laser and channeling the laser through a KTP crystal. Judging from my humble knowledge of second harmonic generation, That should create a 1 watt violet laser beam. Correct?

Topic by Nexoid   |  last reply

Flugtag world record

Red Bull's Flugtag event is normally an event where the focus is on ridiculous contraptions falling into the water. But sometimes people actually do come up with ideas that actually get them some distance. Here's a video of the new record of 207 feet set by Major Trouble and the Dirty Dixies. For comparison, the second video shows a typical Flugtag launch. via Neatorama

Topic by fungus amungus   |  last reply