post in the comments your coilgun, capacitor bank, and how your coilgun works. I want to know everything about it. EX: how long your coil is, how many layers your coil is, how you built it, etc. The more you put the better. I also would like some advice on my new coilgun I'm building. I want to use flash-capacitors and 26-gauge wire. I don't want to use a lethal amount of electricity if at all possible. Thanks!

Posted by Pyrofan 7 years ago

The making of a multi-staged coilgun

I want to make a coilgun with 2 or 4 stages; however, I don't have much experience with capacitors, magnetic fields, etc.. I am not really making it now, but its more of preparing the steps so when I do start, I will be able to complete it and be aware of problems that may occur. 1) when the coil is fed with electricity, what is stopping it from shooting right back at you? 2) how much voltage should the coils be using (aka what type of capacitor should I use) 3) I have heard that capacitors will sometimes have left over charge in them, how would I "dump" the excess. 4) Using multiple stages, should all the coils be turned on at once or in succession 5) should the wire coiling the tube be uninsulated? Here is a diagram of my current understanding of a coilgun. Let me know if it is not correct. Power Supply (battery) --> switch --> capacitor -->wire that wraps around the pipe, creating a magnetic field --> magnetic field pulls projectile into the tube and launches it.

Posted by Brinith 5 years ago

Transformer coilgun

Hey i use a camera circuit for my coil gun and the circuit would always burn out so i was wondering if it is possible to just use a audio transformer and if so how please.

Posted by Kante Tech 7 years ago

DIY Coilgun very pretty, not so deadly

Want to scare someone with a pretty frightening looking gun? This DIY coilgun will get that job done. With the projectiles going out at only 100 fps this is far from a deadly weapon, but just look at it! The $130 pricetag is almost enough for the looks alone. Full specs below.Fully semi-automatic, up to 14 shots.Capable of delivering over 18J kinetic energy, and speeds up to 110km/h! (42 gram projectiles).It's a single stage gun, using a 8800uF capacitor bank with max 400v (704J).Max shot efficiency is 2.8% but reaches almost 4% at lower voltages.Charge time for 300v (12J kinetic energy 396J capacitor bank) is 8 seconds for the mains connection, and when using the internal batteries about 90 seconds. It also has a Digital voltage display.Coil overheat after 14 shots at 300v.Total weight: 5 kilogram.Total spend: ~ 100 EuroConstruction time: ~40 Hrs DIY Coilgun via engadget

Posted by fungus amungus 9 years ago

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?

Posted by renkun67 7 years ago

Spudgun, slingshot, coilgun, paintballgun, airsoft, bow and arrow laws

In Nj, is it legal to own or make a airsoft gun, slingshot, bow and arrow, coilgun, or pneumatic spudgun?

Posted by starwing123 9 years ago

6 Farad Coilgun

I recently came across 4 1.5Farad capacitors and made them into a capacitor bank, but I just want to get a general idea what would happen if I made a 6 farad coilgun...would it go through walls or anything?

Posted by adrewmc 10 years ago

Charging a 8kj capacitor bank

Hello I have a 8 kj capacitor bank and am looking to charge it with dc power I was wondering if I could use a power supply such as this: Any feedback will be helpful Thank You-TDC

Posted by ThinkDesignConstruct 3 years ago

Specifics of building a multi-stage coilgun?

So I recently decided that I wanted to build a coilgun. I already knew how they function, and after some light research, I've got the main design already laid out. What I'm looking for now is some more detailed input on the exact power requirements, circuitry, etc. Specifically: Firing a standard .177 steel BB, I want to use many small coils in series as opposed to one/few large ones. From my understanding, this will provide better end speed while keeping each coil's power draw relatively lower, and thus safer. (Am I right about this?) How many coils should I use, what would be overkill, etc? Each coil will be triggered sequentially by a IR LED/photocell trigger system rigged through tiny holes drilled across the barrel. Will a simple on/off circuit suffice, or will the projectile pass by too quickly for the full charge to release? If so, I assume I need a system to trigger a full discharge when tripped. Correct or not, and if so, how? I'm also considering fitting an extra gate at the end to trigger a circuit to bleed any remaining charge. Ideas on this? What size of capacitors should I use, and how would I charge them? The only thing Google can seem to turn up is camera flash circuits, but I'd much rather have one tailor-built to the system's exact levels. I'm going to use a press/hold switch to charge them, and would like an automatic shutoff with an LED that comes on when they are charged, but turns off when I release the button. Kind of like a camera flash, actually. I'd like to fit it with a re-chargeable battery. What sort of power is required here? How many firings would I likely get per charge, etc? What sort of muzzle velocity can I expect? I don't want to kill bears with it, but soda cans would be nice. I don't want to waste my time fabricating it only to be able to stop it with my eyeball. Lastly, are there any other points of concern or things I should know? Thanks for any input, and if everything ends up coming together nicely, I'll be sure to properly document the process for everyone's enjoyment. :)

Posted by Skye Pyro 5 years ago

Coilgun Help

Could someone please help me with a Coilgun project- I can't get a camera flash circuit of any description where I live, so could someone either post an i'ble on how to make one, or send me/post one of those technical drawings and parts list. Help would be greatly appreciated

Posted by minerug 9 years ago

Where to Get Charging Circuits other than from Disposable Cameras?

After a month of procrastination, I finally got myself to make a coil-gun by choosing it for a science project. I am going to go to nearby Walmart, Radioshack, etc. for used disposable cameras, but it is unlikely I am going to get them. Since I am pressed for time (2 weeks for creation and experiment), I figured I should just post this now. I know I can get capacitors, but what specification should I look for?( around 400V give and take) Also, I need charging circuits ( or another method to charge it with) but don't know where to get them. Since I am pressed for time and still am a novice to electronics, somethings like a DC to DC HV converter would take too long with my amount of expertise. Please help and Thanks in advance

Posted by Brinith 4 years ago

Multistage coilgun

How do you connect multistage coils on a guil gun. Also what matters for a coilgun the ufs or volts.  

Posted by Kante Tech 7 years ago

My coilgun capacitors aren't going above 30v

I made a coilgun out of disposable cameras. i have 6 capacitors running in parallel. I followed these instructions   .When i power it on the capacitors make their usual noise and they start charging fine then when they hit 25-30v they shut off and don charge any further. What is going wrong? The power source is 2 AA battery running in parallel 

Posted by eric95204 4 years ago

Quick coilgun Capacitor question

Im using chargers to rank 330V or even 370V. Heres my options. 400V 330uF Capacitor 450V 150uF Capacitor Im guessing the 330uF, But what's better for a coilgun? (using 4 of them in parallel, yet buying 10.)

Posted by Killa-X 9 years ago

Multistage coilgun need help

I need help.  I was able to make a single stage coilgun, Now I have a few questions regarding extra phases. The coilgun i have has four 300+ Volt capacitors with capacity of 470 uf.  1)How do i activate them? Would it be possible to use a sensor switch like this? ( If not, what would you recomend? 2)Would it be possible to make it so that after projectile passes a secondary phase, the phase starts to recharge automaticaly?  Please help, and thank you!

Posted by mondeluz 2 years ago

12kj coilgun project

Hello I am working on a new coilgun using 15 10000 uf 400v 17200 ma capacitors. The accelerator is 5 stage, while using 3 caps per stage each stage will have 2400j of energy. I will be posting updates on this forum every month or so. my current setback on the project is charging what I am wondering is what input current and voltage and output current would I need to charge 3 caps decently fast. once that is solved I will line up 5 in parallel to charge all (1 per stage) if I need to line up a greater amount of a lower rated circuits I will.

Posted by ThinkDesignConstruct 3 years ago



Posted by cazmundi 11 years ago

Building a full auto coilgun

I've been working on this project for about a year now, the first stages of the design started like 5 or 6 years ago. It is a full auto 19 stage no-capacitor coilgun. The accelerator is 3ft long! It will use an advanced coil timing system that should allow more efficient acceleration. The custom 3d printed magazines will hold about 90 shots, maybe a little more. It should be capable of firing at a rate of several thousand rpm but I might tune it down to ~500 rpm to keep it cooler running and make the ammo last. If you want to read more about this design you can see the page on my website:!em-guns/cwjy Here is a video showing the current progress on the coilgun:

Posted by Jaycub 3 years ago

Looking to make a new coilgun, need answers

I was going to start a new coilgun now that i've learn more about the coil it self (last one shot 3 inches , bad coils!Whats the best capacitors to use? - How many volts and UF? - Where can i get them for a cheap price?What tips do i need to know to keep the capacitors safe, as long with me (besides DONT TOUCH CONNECTIONS WHEN ITS HOT!) lol....I can use camera flash circuits to charge the caps, just don't know whats best to get :(

Posted by Killa-X 10 years ago

Building a charger circuit for a coilgun by adding a bunch of smaller charger circuits from cameras together.

A while ago I ran across an instructable detailing how to connect a bunch of charger circuits from disposable cameras together in order to make the capacitors for a coilgun charge faster. I went about cutting the important parts of the circuit out of the rest of the PCB inside the cameras, but the instructable has since disappeared and now I'm left with a bunch of separated charger circuits that I need to add together. Does anyone know how to do this? The pictures are examples of what I've got. I have 11 of them.

Posted by GameKyuubi 9 years ago


Im building a multiphase coilgun but encountered a problem. In order to activate secondary phases i need a photoelecric switch. In my case it is TCRT5000 photoelectric switch. The problem, however, is that once the ''beam of light'' is shining on it, the switch is turned on, but i need it to be turned off when ''beam'' is directed at the diode and turn on when the ''beam'' is not directed at the diode. How do I do this? And in this case changing polarities wont change anything.

Posted by mondeluz 2 years ago

Help with charging capacitors

How do I charge my 450v capacitors with a 120v outlet? I am building a rail gun and need to get these up to a high enough voltage. 

Posted by gclark0812 11 months ago

Coilgun, Marx Generator or Voltage Multiplier

I am building a coilgun and I have constructed a coil with several thousand turns, an ohm meter measures its resistance at 300 ohms, so I am having trouble powering it, I ran 240v through it and got nothing. According to my calculations, I need to run 1000 volts at the minimum through the coil in order for it to work. From my research there are three ways to do that: 1)A really big transformer (sub optimal for many reasons) 2)A Marx Generator 3)or with a Voltage Multiplier. Now I realize that you are supposed to connect the voltage multiplier to the Marx Generator, but wouldn't it be easier to just to make more multiplier stages and remove the Marx Generator entirely? I've seen voltage multipliers go up to 15kv, which is more than enough.

Posted by geekman2 4 years ago

Capacitor bank for Coilgun help please!

I havetwo 680 uF capacitors, rated for 200 volts.. And I want to use a disposable camera charger to charge them both. The camera charger stops at 300 something volts, and when I wire them up in series, I get 400 volts, right?.. I want to charge them and discharge them into a coil of wire to launch a projectile at a fair velocity. , I can work with up to 10k wraps of wire, and i have only two capacitors and a major one.. First 2: 680 uF 200v 680 uF 200v Major one: 180 uF 400v Now I imagine I'd get more joules with the two smaller ones than the big one because of the microfarads, right? These specific type of capacitors are made from Elite, and are electrolytic I think, and I got the major one from a computer CRT monitor, and the two smaller ones from a computer power supply.... I also have a 3.3uF 50v capacitor. Now the question is: Can someone help me add these together to increase maximum joule output? I want to hook up the two 680 uF 200v capacitors in series to get a maximum voltage of 400. Then I want to add the major capacitor, which is 180 uF in parallel with the two other capacitors to increase microfarads, in this case, it'd be: 680 680   + ------- = 680 (because they are in series) ------- + 180  = 860 I want two capacitors in series, and the major in parallel, increasing voltage to 400 volts, and the major capacitor doing nothing but adding capacitance (IF possible) Sorry, this is alot to ask for you guys to answer, If none of the above can work, What would work better, the two 680 uF's in series, or one big 180 uF 400 volt capacitor? I apologize if I cannnot explain my question properly.... it's very hard to understand capitance and series/parallel blah blah mumbo jumbo. Thank you.

Posted by Justdoofus 7 years ago

Using LiPo batteries in coil guns

Hello all, this is my first post! I have been theorizing for a while about coilguns, and have been doing calculations. here is how it goes: A single Lithium polymer battery can hold up to 3.3 Ah and discharge at about 30c (safely). We multiply 3.3Ah by 30c and get 99 A of continuous discharge. That’s a LOT of current, but, it is still not enough to fire a good projectile. So, I’m planning on having four of these hooked up in parallel to give out 396A. This is quite a bit of dangerous current, so my wiring will have to be gauge-perfect. The magnetic field that this produces is about 9.9 teslas, as  twice much as your average MRI machine. Yes, I’m utilizing a miniature MRI to shoot stuff. If you want to know how much force an MRI puts out, here is a great video to show you I am planning on having a 2,000 turn coil, with the average distance from the projectile being 1cm. The ammunition is going to be BB bullets, which means our cross-sectional area is at least 7.65*10-4m2. Using those numbers, the initial force on the BB is 3,015,030N. This is enough to lift up 25 semi-trucks. On paper, this seems magnificent. However, I’m accounting for about 2% efficiency, taken into account at this step, giving us 60,300N. This is still an enormous force to take to a .5g BB I’m implementing the Impulse to be .05s using standardized E = F * t,  this gives us 3,015 joules of energy. Huh. that’s way more than we should expect. Let’s take into account the 2% efficiency rating again, and we get a more realistic number: 60 joules. 60 joules is ridiculous for a BB pellet. We’ll use Ek = 1/2*m*V2 to solve for V. I got about 1,553 m/s. This is faster than most guns shoot regular bullets. I will be using a 2-stage setup, and will make sure to  use proper electrical equipment. My question to you is; How accurate are these calculations? if I build this thing, what can I excpect?

Posted by bjohnson45 4 years ago

Free disposable camera's or their capacitors

I want to try my hand at making a very powerful coilgun but I live in a small town and our photography store doesn't sell used cameras for less than $3 each! Which means $30-40 or more for the coilgun I want and I don't have that much to spare :( So I'm hoping someone in Australia can possibly send me as many used cameras or capacitors as they can spare, I'd be willing to pay for them as well as shipping

Posted by grantdevine 9 years ago

Making a coil >.<

Grrrr, so I'm making my and I have everything done, but I can't make the coil, i try winding but it turns out pretty messed up, and hard to take off, is there any other way to make the coil?

Posted by astrozombies138 10 years ago

23 stage no-capacitor full auto coilgun

  *********I have updated my design since posting this topic. The video is the more current design than what is written below.**********    I came to the conclusion that using capacitors to provide the power for a coil gun is a stupid idea. A bold statement I know. The reason is that they are big and heavy, take time to charge, and need charging circuits. Also, the sharp rise in current that comes from capacitors is bad unless you are making an induction style coilgun, because the induced currents will hurt efficiency.    If coil guns are ever going to be a practical hand held weapon it will need to be lighter, simpler / less delicate, and more powerful than what you will find on the internet if you look up coil guns. A rate of fire that is competitive with conventional guns will also be needed if a coil gun will be used for anything other than target shooting or maybe hobby hunting. So I designed a coilgun to meet these requirements. Visit my website for a full explanation of the design:!em-guns/cwjy     I realized that a coilgun would not be a practical infantry weapon until batteries are more advanced anyway, so that just adds to the list of why capacitors are out. It will be powered directly off of the batteries, and have many coil stages. This allows a very high rate of fire. To get that rate of fire with capacitors you would need several capacitor banks charging at offset times, so after each bank fires another is just finished charging. That would be terribly bulky.    The lower voltage from the batteries will give comparatively slow current rise in the coils which normally would make the coil timing weird. I plan to use an unconventional coil timing though. All the coils will be activated at once, and the coils behind the projectile will be shut off as it passes them. This will have several advantages: -The coils will only be powering up for a split second at the beginning. Most coils will already be at full power when the projectile gets to them (that is not the case in most coil guns). -Induced current will not be any issue. -Since the coils will all act as one coil, the projectile will be drawn toward the center of all the coils that are on. Timing of the shut off of the coils will not need to be perfect.    This will be a pre-tuned passively timed system. I want to use a small adjustable electronic timer for the switch-off timing. This will require some work in the initial adjustment of the timing, but even actively switched coil guns (with optical sensors or something) require that. the advantage of a passive system over an active system is cost and simplicity, and you can pack the coils tighter on the barrel if you are not putting a sensor between each stage. That matters with 23 stages! As I said check out my website to see more details and pictures for this and other projects:!em-guns/cwjy

Posted by Jaycub 5 years ago

flying taser

I'm working on a flying tazer and have everything primed and perfect, but i can't figure out how to shoot the thing!!!!!1 along the lines of springs, compressed air, or electricity ( coilguns )please...

Posted by instructa-fan 10 years ago

Coilgun/Railgun idea

So i have been researching and thinking about this project sence the magnet contest. basicily i was thinking hey why not combine the 2 with the coilgun i would get a ton of good acceleration. then it would hit the rails and be jolted forward . it would minimize the time the round was in the rails and give them the best chance to do there job. So i would be using a ferrious round with aliminum at the rear to act as the armiture. To get better flight path out of the gun i would take a copper pipe for both the coil and the rails but for you cant have the 2 touching so ill space it with somthing like pvc. correct me if i'm wrong but i heard plating copper with silver would give a better result for rails the final keystone will be the capacitorbanks and controllers (i don't know much about microcontrollers so any help there...or anyware would be great) my idea was to stage a bank per coil and rail that way each would fire it's full load when the round got to there what do you guys think? info please. this is a new project so if anyone has the time and wants to try my idea let me know what your results turn out to be

Posted by Jack Daniels 11 years ago

Do you make other people's projects?

A question from Plasmana set me wondering - Do you follow other peoples' Instructables?Personally, the answer is mainly "no" (sorry Plasmana).I keep meaning to, I just never seem to have time to...I want to make a Kelvin's Thunderstorm, a VdG, Plasmana's shocker, a coilgun, a tiny robot, a plushie. I did make a vacuum cannon, but before I saw this site.What have you made from other peoples' projects?What do you plan to make?

Posted by Kiteman 9 years ago

Low Cost Electronics Parts & Supplies

if you are looking for electronics parts for you projects please visit my website. it is still under construction so give me time to add more parts to the inventory. Thank-You.

Posted by silencekilla 8 years ago

People and Compact HIgh votlage capacitors

This is just a little anouncement. To all you people making coilguns and micro tesla coils and other highvoltage devices that require a rather large capacitor (and this goes to all circuits) and who try to save space to make a smaller, sleeker design (no one wants a bulky coilgun). 1) DO NOT put capacitors in series, just buy a capacitor on ebay that can withstand the voltage. about 90% of the time (I have only found one occurence where I got a smaller package for putting capacitors in series) you are wasting about half (or even more) of the volume. When you put capacitors in series, effectively you are just doubling the dielect width, and just wasting a lot of the conductor room (inside the cap, forgot the name) because it's not being used!!!! 2) Put Capacitors in parallel. Most of the time 10x 1kv, 1uF caps in parallel (1kv, 10uF) will take up much less room than 5x 200 volt 5uF capacitors in series. 3) I'm not sure if you can understand #1, if so, my bad. Basically you waste somewhere between 20 and 80% of the space, depending on how many caps in series you have. Just felt like throwing this out there because I see so many inefficient designs...

Posted by guyfrom7up 9 years ago

Pulse Generator, part suggestions?

Hey, I want to make an external pulse generator, mainly so I can power a simple coilgun. I know I have to have a bunch of capacitors hooked up in parallel, but what value would be ideal? And what kind of transformer do I need? Say I use a 9v battery, how would I calculate the ouptut voltage? I know trial and error would work best for me, but I don't have any transformers lying around so I need advice on which one to get. Thanks.

Posted by Jackhole 10 years ago

Can I charge multiple capacitors without a DIY DC/DC converter?

I'm starting to build the coilgun in rwilsford07's instructable but he says that camera circuits are very ineffecient and to try a DC/DC converter like in his other instructable but I'm hesitent to build it because it uses a wallplug to draw power from the mains and if something goes wrong I'm a dead man. So I'm wondering if there's a way to quickly charge the capacitors using car batteries (which I've got several of) or with an even larger capacitor (I've got a 2100v AC capacitor) Or would it be easier to buy somethng to suit?

Posted by grantdevine 9 years ago

Disposable Camera Hack?

Hi, im building a capacitor bank for my coilgun, and I have 17 disposable camera capacitors in them. (wired in parallel (or whatever one means + is atached to +, and - is atached to -)) But for some reason wenever I start chrging it, after a little wile, it makes a huge spark across one  of the capacitors. That probobly means its arcing right? but its only 300 volts (there wired in parelell so only the amperage goes up, not the volts).  I then tryed to charge the caps to a point before they arced, wich took about 1 min (the battery is full) and my ammo only shot 3 inches! 17 capacitors, charging for 1 min, and it slid across the floor 3 inches! I have no idea what im doing wrong. Im using wire from a microwave motor  (wich is realy small) for the coil, and its 5 layers thick, wrapped around a hollowed out pen. So, to sum it all up, here are the main problems: 1) the caps arc when charging 2) the ammo only goes 3 @#%!ing INCHES!!!!!! arg! Ps, i heard someware, that if you have enought amps, it will arc even with lower voltages. Maby thats whats happening?

Posted by Stuffses 8 years ago


AHHH, Hello everyone. I'm a filipino male college nursing student and a hobbyist. Concerning about the capacitor chargers that I have found about this site and which I'm common about using disposable camera as charger. Well here's my problem and the one I'm finding difficult for my self because I have just only a very little Knowledge about Electronics. For the many sites I visit none of it provides me an easy way of Building a Capacitor charger with LED indicator not using a disposable camera. What I need was a detailed and step by step instructions and easy for me to understand schematics and also the parts needed and its values cause sometimes i'm having troubles and difficulties for electronic symbols about on making a capacitor charger including all their connections or were to connect and wire those parts. I also find it difficult to build because some transformers have 5 pins or leads like on disposable cameras while the big ones have only 4. I'm building my own coilgun and it really works, now what i need was how to build a Fast charging capacitor charger like those that I found on many sites. Just like a other professional and amateur hobbyist I'm just a little one who was just starting. I would really as in really appreciate all the helps....THANKS!!!!!!!! And by the an easy steps in making a homemade stepup Transformer using a house hold materials would also be helpful!!! Thanks again!!! Here's my E-mail>>>>>

Posted by KITKAT69 11 years ago

Coil Gun Project

Hey guys, I am currently building my first coilgun, first of all, the components: Charging:     Disposable camera circuit x 2     2 x D cell batteries Capacitors:     2 x 1200uF 200V     2 x 680uF 200v     2 x 300uF 200V     1 x unknown (attached to camera circuit with no info) Switch:    250V @ 15A - 6 pole toggle (I will upgrade to some for of solid state when I have the money) Now, because I have two of each capacitor I have put one of each into a parallel bank, giving me 2 cap banks with one of each cap, I then connected the two banks in series, I have not done a lot of maths yet which I think I should but I was hoping that would give me 400v which seems to be average. The problem is, it is only charging to 340v tops, I think that may be due to the camera circuits being wired incorrectly. I have the two batteries in series, both charging both of the circuits, then the circuits both charge the caps, the + and - outputs meeting on the caps, am I doing that wrong? Also, does having 300uF caps in series with 1200uF caps hinder the bigger ones? Would I be better of with just the 1200uF and 680uF, or maybe even just the 2 1200uF in series? should I also leave the small cap on the circuit or take that off? Thanks in advance guys, any help would be greatly appreciated. I am having a lot of fun with this project and while I wouldnt like to be on the other end, it is still not as powerful as I would like, even for it's small size.

Posted by TristanD27 4 years ago

September Project Contest Winners

The votes are in! Congratulations to the winners of the September Project contest!September Project Contest First Prize winnersAtomic Zombie's ChopWork Orange chopper bicycle by KoolKatCyanotypes - super easy photo prints at home. by ianFloppy Disk Bag by imanalchemistHandbound Book by BrianSawyerA Traditional Jacob's Ladder by ereinEach first prize winner with receive a Digital Spy Camera from Wild Planet Toys.September Project Contest Second Prize winners3D DDR Frame for PS2 by impulse94DIY Home Bicycle Repair Stand by pizzFixed Disc Sander from Angle Grinder by divxnzHydroponics - at Home and for Beginners and Solutions to Hydroponic Problems (Lack of Root-Plant Support) by trebuchet03Insulating Laptop Pad by Bats22pvc kayak by hellokellerStanding Desk Conversion Platform by 5dotsTen Green - modular shelving by royshearerTyvek FedEx Wallet with Change Pocket by cheewee2000Willow Twig Furniture by SlimJimEach second prize winner will receive a Magnetic USB card reader. Some assembly required!Honorable MentionAncient Aeolipile -steam engine, and magnets for good measure... by trebuchet03Can in Can Grill by nabilahmadDaisy Duke Toolbox by SlimJimDisposable camera coilgun by AlfonsVHDIY: EXTREME Power saving wireless mouse mod by Corbin_DallasEasy and tasty stir fry by SupercookieFolding Game Board by degroofFreezing summer tomato crop by shecktorGuacamole by easementHow to build a heliostat parabolic reflector by Tool Using AnimalHow to Build Up a Bike by joeHow to Build your own 1u Linux Server by jonesygoodstuffHow to make a RAILGUN! by AlexTheGreatHow to remove Logos from your PDA / cell phone with sugar by spankvalMagnetic speed sensor by PeterTheUnGreatMagnetic Tool Rack by packrathackerMicrodot - wrist watch LED pattern timepiece by rgbphilMonica's wedding cards by outofthewoodsOpenface Bagel Sandwich and Another gooood sandwich by eraaawghhhParty top-hat made of playing cards by Sergey ChernyshevPay-per-Copy Machine Exploit by nakPower to the Super Rebound by frickelkramSolid Perfume by rapierwittrailor project by trusted smilesVinyl Pencil Case by splityarnEach Honorable mention winner will receive an Instructables patch. It was really tough judging so many awesome projects. I hope everyone had fun building and documenting their projects. I'm sure you'll have fun going through the winners; it's really an incredible list!Thanks to everyone to who entered and to the people who helped judge the challenge: arwen, canida, dan, fungus amungus, intoon, leahculver, lebowski, and rachel.Original September contest instructions here, information about the SpyCam here, and information about the Magnetic USB card reader.

Posted by ewilhelm 11 years ago

A Hybrid of Coil and Rail gun

So I said i'd throw this up in the comments section on Youtube not too long ago, and I don't like it when something easy and free doesn't happen. This is some ideas and observations that have to do with coil guns (mostly). I'm in the process of finishing up several projects, so my resources are kinda spread out. I should have a prototyped coil gun finished in 2-3 weeks though, so if this doesn't clear things up, hopefully that video will. I should point out, I am a chemist with expertise in biochemistry, not electrical engineering. Basically my idea is to combine a railgun and a coil gun for the expressed purpose of avoiding the pitfalls that a pure coilgun or a pure rail gun have. At present, none of the designs out there would be capable of competing with an actual gun. By mixing the two, i'm hoping to get something that might eventually be capable of doing so. So.. I've included a very poor drawing (I'm not an artist). The barebones circuit is sketched in the lower right hand corner. The gun barrel, which is a piece of aluminum tubing split into two pieces to sever as a rail system, is sketched in the upper left, and again in the middle figure to show how to integrate the coil and rail system. Looking at the circuit design, you can see that this starts off as a very basic capacitor-inductor circuit. The charge is purposefully allowed to trickle through the circuit until the coil reaches saturation and the capacitor(s) are charged. When the trigger is pushed, the inductor side of the circuit has to dump into the rail system to complete the full closed loop. Because of the ferromagnetic material (the brown stuff), the magnetic force persists for a while (that is to say, it has high reluctance). The ferromagnetic material does one other thing that is important here. It forces the middle of the coil to be far off center. The coil is pulling the projectile into the middle of the magnetic field, but that is not necessarily in the center of the winding. Adding ferrite, or other high reluctance material, towards the end of the barrel biases the field towards that end.  At the same time that the coil stops getting current, the rail system become active. This allows a charge to pass through the bullet/projectile, and, even though the majority of the force is going to be caused by the inductive coil, the rail system allows an eddy current to setup in the bullet. This does several things. First the bullet doesn't have to be iron, nickel, or cobalt. With a stray eddy current in the projectile, any conductive material will work. The advantage here is that once the current stops, the non-magnetic material stops being  to the magnetic field, preventing backwards acceleration of the projectile as it exits the barrel.  Second, Rail systems and coil systems are not often used because they are perpendicular to one another, but, this can be used to put spin on the projectile, in a similar manner to rifling in a barrel.  After the projectile is fired, the circuit is open, preventing excessive electrical discharge.  My circuit design is really badly drawn... =T if it needs more explanation please post up questions. 

Posted by Qcks 4 years ago

Instructables Book Contest Winners

Instructables is happy to announce the winners of the Book Contest. All of these Instructables will receive a mention in the Best of Instructables Volume 1 and the authors will receive a copy of the book when it comes out this fall.Some of the Instructables here have also been selected by O'Reilly editors to be fully reproduced in the book as well.Congratulations to all the winners! Thank you for making great Instructables that inspire everyone else.InstructableAuthorLED ThrowiesQ-BranchInvisible Book ShelfdorxincandelandLaser Flashlight Hack!!KipkayMintyBoost! - Small battery-powered USB chargerladyadaDIY Compact Survival KitledzeppieHow to make a cardboard costume helmetHonusturn signal biking jacketleahbuechleyAudio Visual Art....FOTC Stylescooter76Wall-E Robot4mem8Paper WallettheRIAAScreen Printing: Cheap, Dirty, and At Hometracy_the_astonishingMunny Speakersfungus amungusKnex Heavy CannonI_am_CanadianHow to Make Playdough (Play-doh)canidaLED Chess SetTetranitrateSew your own Instructables Robot Plushie!jessyratfinkDIY Vinyl Wall ArtbritsteinerBluetooth Handgun Handset for your iPhone: iGiveUpManaEnergyPotionEasy to Build Desk Top 3 Axis CNC Milling MachineTom McWireBuild Your Own Butler Robot!!! - Tutorial,Photos, and VideoErobotsHow to build a 96-Volt Electric MotorcycleKentucky-bumHow To: Make Bath BombsSoapyHollowSteampunk Dystopian Sniper Rifle (Mercury Bow)gmjhoweSave $200 in 2 minutes and have the worlds best writing penkingantConcrete Lightbulb Wall HookwhamodyneLight Bulb LampbumpusLightbulb "green"houseLinuxH4x0rInstructables Robot -- Paper Model=SMART=How to Build a Robot - The BeetleBot v2 ( Revisited )robomaniacWallet made from a computer keyboardzieakhow to add EL wire to a coat or other garmentenlightedGandhi: 17' Tall Cardboard AvatardelappeTure Trigger, 10 Round, Auto-Loading, Knex Concept Rifle, by bannana inventorbannana inventorHow to build your own Jet EnginerusswmooreShake it like a Tic-Tac!MrMunkiCyber/Steampunk Futuresque Sci-Fi Hand GungmjhoweHow to Make a Marshmallow Gun or Marshmallow ShooterewilhelmHow to build a 72Volt electric motorcycleStrykerFriends Are Easy To MakecuteaznprincesssBuilding Small Robots: Making One Cubic Inch Micro-Sumo Robots and Smallermikey77Portable 12V Air Conditioner --Cheap and easy!CameronSSHow to Make a TRON Style Lamp: The MADYLIGHTGreg MadisonGiant MatchTetranitrateMagnetic Rubik's Dice CubeburzvingionHow to build a wood fired hot tubveloboyIron Man HelmetpmaggotHome-made Sun Jarcre8torGrow Your Own Bioluminescent Algae ScaryBunnyManConstruction of Two Portuguese Style Dinghies (Small Boats)rook999Uni-Directional WIFI Range Extendertm36usa"1UP Mushroom" Mushroom Burger!momo!Open Any PadlockTetranitrateCoilgun Handgunrwilsford07Electroforming an Iris Seed PodMaggieJs100 Ways to Reduce Your ImpactBrennn10Lego USB StickianhamptonSolar Powered Trikedpearce1How to Make a Three Axis CNC Machine (Cheaply and Easily)Stuart.McfarlanAirgun with eXplosive air-Release ValvechluaidChapStick LED FlashlightBCatAwesome led cubeAlexTheGreatBarbie Doll Electric Chair Science Fair Project!jessyratfinkDIY 3D ControllerkylemcdonaldThe Stirling Engine, absorb energy from candles, coffee, and more!thecheatscalcBuild a World's Smallest Electronic Shocker!PlasmanaSimulated woodgrain for metal boxesamz-fxHow to Grow Pineappleswoofboy111Creating a 3D effect with image editing software (GIMP or Photoshop)Andrew546S.P.R.E.E. (Solar Photovoltaic Renewable Electron Encapsulator), a Compact, Durable, and Portable Solar Energy GeneratorcharlitronHow to get a Tshirt for GoodHartRocketScientist2015Grow a square watermelonwatermelonBuild a 4 Color T-Shirt Printing PressProgfellowElectromagnetic FloaterJ_HodgieThe accidental pocket jet engine...killerjackalopeDigital Picture Framemicahdear

Posted by fungus amungus 9 years ago

Top 50 2008: Instructables

Yesterday we looked at the Top 50 commenters for 2008 and today we'll be looking at the numbers for the top 50 Instructables of 2008. Since there's no one way of declaring a list of Instructables, we created three top 50 lists. These cover Instructables in order of rating, pageviews, and comments. Instructables on these lists were all published in 2008.Let's go to the graphs and charts!Top 50 Instructables: Pageviews   Instructable Views 1   Body-Mod: Elf Ears 347738 2   Use your laptop as an Xbox/Xbox 360 "Wireless Adapter" on Windows XP/Vista, and Mac OSX 220780 3   Fix the Red Ring of Death! (without towels!) 177285 4   Laser cutter, start slicing stuff for under 50 dollars 159647 5   Run Backups on any Wii Without a Modchip 159408 6   How to build a 72Volt electric motorcycle 159261 7   How to make out 145713 8   Inverted Bookshelf 137198 9   Munny Speakers 124736 10   Awesome led cube 118293 11   Firefox Pranks! 117449 12   How to make an Iron Man Arc Reactor 116481 13   How to French Kiss 115958 14   How To: Make Bath Bombs 108287 15   Gift Ideas 107914 16   DIY USB "Hard Drive" 96588 17   Safely Shaving Your Pubic Hair 96144 18   WinXP Overhaul Guide: How to make it look like Vista, run like lightning, and stay productive, fast & smooth 94980 19   Laser Tattoo 94705 20   DIY Vinyl Wall Art 92752 21   How to refill a "disposable" Brita brand water pitcher filter with activated carbon. 89724 22   Make your own Roll-Up Keyboard 89558 23   Hidden USB Storage 86430 24   how to add EL wire to a coat or other garment 84340 25   Build a 60 Watt Solar Panel 82286 26   Grow a square watermelon 82275 27   LeGummies brick shaped gummy candies 81368 28   USB 80875 29   How to remove most of the seeds when cutting up a watermelon 80822 30   How to Make a TRON Style Lamp: The MADYLIGHT 80281 31   LED Cube 4x4x4 78936 32   Covert Spy Sunglasses 78633 33   Build a water mortar 77090 34   Super Nightvision Headset Hack! 76634 35   A better laptop stand for bed 76101 36   Amazing plasma globe tricks that you never knew before!!! 74842 37   How to get a Free Itunes Account (No Credit Card Needed) 74490 38   Make an iPod Video Projector 74026 39   Homemade Gifts 73478 40   Lasers 73242 41   Remote shutter trigger for Digital Cameras 72911 42   Ergonomic Laptop Stand Made From a Coat Hanger 72321 43   MAKE A HIGH VOLTAGE SUPPLY IN 5 MINUTES 71744 44   Protect Your Home with Laserbeams! 71387 45   Iron Man Helmet 71358 46   Get Big Money for Dead Batteries 70261 47   How to Put on a Condom 69805 48   How to make an Iron Man Mask 69617 49   How to build a 96-Volt Electric Motorcycle 68924 50   Nintendo Lunchbox 68164 Top 50 Instructables: Ratings   Instructable Rating 1   Build A Plasma Speaker 4.64 2   Build A Net Gun 4.62 3   Wall-E Robot 4.60 4   Sew your own Instructables Robot Plushie! 4.60 5   How to Make a Portable Game System 4.54 6   Build Your Own Butler Robot!!! - Tutorial,Photos, and Video 4.54 7   Electromagnetic Floater 4.52 8   LED Cube 4x4x4 4.50 9   LeGummies brick shaped gummy candies 4.49 10   DIY Vinyl Wall Art 4.49 11   5-minute Chocolate Cake 4.48 12   When a Phillips is not a Phillips! 4.48 13   Airgun with eXplosive air-Release Valve 4.47 14   How to Build a Robot - The BeetleBot v2 ( Revisited ) 4.45 15   How to Start a Business 4.45 16   Gandhi: 17' Tall Cardboard Avatar 4.44 17   turn signal biking jacket 4.44 18   Hidden USB Storage 4.44 19   Cyber/Steampunk Futuresque Sci-Fi Hand Gun 4.43 20   LED Chess Set 4.41 21   Build your own Electric Car! 4.41 22   LCS-1M - A Full-Featured, Low-Cost Hobby Oscilloscope 4.40 23   Build a World's Smallest Electronic Shocker! 4.39 24   Lego USB Stick 4.38 25   MAKE A PILLAR WITH A DECORATIVE CAPITOL AND BASE 4.38 26   EGG FLOWER VASE 4.38 27   Aliens Powerloader Halloween Costume 4.38 28   Munny Speakers 4.37 29   Giant 100mm LED 4.37 30   Coilgun Handgun 4.37 31   How to Thank Instructables 4.36 32   Guitar Tube Amp 4.36 33   How to get a Tshirt for GoodHart 4.34 34   Creepy Cobweb Shooter! 4.34 35   Grow Your Own Bioluminescent Algae 4.32 36   How to make a Portal Gun 4.31 37   how to add EL wire to a coat or other garment 4.30 38   Duct Tape Messenger Bag + Hardware 4.30 39   Firearm Safety: The "do's" and "don'ts" of enjoying guns safely. 4.29 40   The Stirling Engine, absorb energy from candles, coffee, and more! 4.29 41   Recycle Old Light Bulb 4.28 42   USB Batman Spotlight 4.28 43   Coffee table upgrade! 4.27 44   Steampunk Dystopian Sniper Rifle (Mercury Bow) 4.27 45   Building Small Robots: Making One Cubic Inch Micro-Sumo Robots and Smaller 4.27 46   How to grow flowers on a military base in Iraq 4.26 47   How to make your own LED lightbulbs 4.26 48   Iron Man Helmet 4.25 49   Cardboard/Fiberglass Halo 3 inspired Master Chief Costume 4.25 50   Build Halo Armor 4.25 Top 50 Instructables: Comments   Instructable Comments 1   Build a World's Smallest Electronic Shocker! 812 2   Knex Heavy Cannon 645 3   Awesome led cube 637 4   Simple Xbox 360 Rapid Fire Mod 591 5   Build A Plasma Speaker 494 6   DD-27 V2.75 compact AST rifle 454 7   WinXP Overhaul Guide: How to make it look like Vista, run like lightning, and stay productive, fast & smooth 453 8   The accidental pocket jet engine... 427 9   Scavenge free electronics, food, and help the environment 400 10   How to make your PSP "Better" or how to have more fun on a Sony PSP 379 11   Laser Tattoo 376 12   Amazing plasma globe tricks that you never knew before!!! 376 13   DSman195276's sidearm --updated-- v1.5 is here! 371 14   MAKE A HIGH VOLTAGE SUPPLY IN 5 MINUTES 363 15   Wall-E Robot 352 16   Knex Heavy Cannon v5 - Handheld 342 17   Fix the Red Ring of Death! (without towels!) 341 18   How to Build a Time Machine (Vortex Distortion Space and Time Dilating Device) 340 19   Knex Heavy Cannon v2 - Mini 339 20   How to get a Tshirt for GoodHart 338 21   Run Backups on any Wii Without a Modchip 336 22   Make A Water Leyden Jar 331 23   Park 52 knex sniper 327 24   Build a simple Marx Generator 323 25   Knex Guinea Pig Trap 318 26   TRUELY semi-auto knex gun 315 27   L96 308 28   How to Build a Knife 307 29   Pineapplebob's Sniper Rifle 306 30   True Trigger, 10 Round, Auto-Loading, Knex Concept Rifle 299 31   Fire Shaving 290 32   DJ Radio's knex SPEC-9 sniper rifle 285 33   How to UPGRADE from Vista to Windows XP on an Acer laptop 283 34   How to dodge a draft 279 35   Protect Your Home with Laserbeams! 279 36   Hidden USB Storage 277 37   Knex Compact AST Pistol 276 38   Cyber/Steampunk Futuresque Sci-Fi Hand Gun 276 39   Steampunk Dystopian Sniper Rifle (Mercury Bow) 275 40   Pocket sized survival kit 274 41   Knex Pistol "TDS" With Simple Slide Action *Updated as of 8/26/08* 271 42   Use your laptop as an Xbox/Xbox 360 "Wireless Adapter" on Windows XP/Vista, and Mac OSX 269 43   Body-Mod: Elf Ears 266 44   Knex M4 Carbine (True Trigger) 257 45   How to make a Portal Gun 255 46   DSman195276's sniper rifle 254 47   Reaper Crossbow 254 48   fully automatic knex gun (UPDATED) 252 49   Build your own computer 252 50   LeGummies brick shaped gummy candies 252

Posted by fungus amungus 9 years ago