Talk:Coilgun

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In Science Fiction[edit]

A Coilgun is also to be found in "The Neutronium Alchemist", volume 1 of the "Night's Dawn Trilogy". Known as a "Gaussgun" in the book, it is the only man portable weapon effective against possesed humans, until other weapons are developed later in the series.

the gauss weapons in x-com 2 can be fired above and below water, which makes them a valuable dual-purpose weapon -Lordraydens 05:15, 16 March 2006 (UTC)

This article may be mislabeled in some aspects. Mainly that a search for "gauss gun" comes to this page. [[1]] that is what an actual gauss gun is (sorry about the site the video is on but it's the only place I could find it). I don't have the time to write an article about that myself, but it should be changed so that a search for "gauss gun" takes you to a page saying it needs an article as opposed to this article.

Also the mention of Half-Life makes it seem that the gun only helps you move around the map and that it is not used for fighting. 24.196.115.179 19:10, 8 August 2007 (UTC)

It's also used in the Halo series, where a coilgun fires depleted uranium at around half the speed of light. (Called a Magnetic Accelerator Cannon, or MAC in the series) I think this page needs an "In Popular Culture" section. - dreaddraco2, 8PM GMT, 02/03/10 —Preceding unsigned comment added by Dreaddraco2 (talkcontribs) 20:01, 2 March 2010 (UTC)

Paranoia[edit]

Paranoia Gauss guns aren't coilguns, they just fire focused bolts of EMP. (Just leaving a note to that effect.) —Preceding unsigned comment added by Vogon (talkcontribs) February 23, 2006

Too much cruft.[edit]

I came to this article because I wanted to find out how coil guns work. As a reader, I find that the list of trivia from video games at the end to be excessive, unnecessary, pointless, etc. It also makes the subject itself look trivial, even though it is definitely not trivial. I'm going to trim it down considerably or remove it. Revert me if necessary, but please understand how bad it makes the article look to have a list of video game trivia as long as the article itself. Brian G. Crawford 22:01, 28 April 2006 (UTC)

I was surprised too. I'm helping.
I agree, we really need to cut down on the "coilguns in science fiction" and add more real content. Maybe we should move the science fiction section to the end of the article. It does make the subject look like a collection of video game weapons. Lima-1 18:45, 28 December 2006 (UTC)
One of the problems is that there is a lack of actual weapons. Coilgun technology is still in its infancy in terms of a real weapon. Acehunter 20:25, 31 January 2007 (UTC)
They exist, just not to general public. Check out Anothercoilgunsite.com site is by Donnie James in California. Has done amazing amounts of R&D in automatic and high-power coilgun's. --TTLLOGIC 17:44, 1 April 2007 (UTC)

A note on this[edit]

A while back it was decided that if we must include lists of anime that feature weapons like this that it belongs in a separate article - electromagnetic projectile devices (fiction). That's a better place to add new material of that type. Chris Cunningham (not at work) - talk 12:38, 28 April 2009 (UTC)

All magnets on at the start or switching each one on when needed?[edit]

Under the Construction-heading is the following phrase:

"A large current is pulsed through the coil and a strong magnetic field forms, pulling the projectile to the center of the coil. When the projectile nears this point, the coil is switched off and a next coil can be switched on, progressively accelerating the projectile down successive stages."

However, under the Operation-heading it says:

"The gun starts with all of the magnets turned on, and then turns them off one by one before the shell reaches them."

So which is it? --ZeroOne 15:44, 13 May 2006 (UTC)

it can be either, although, given current power limitation and use of capacitors as a power source, it is univerally usually the earlier --88.106.60.51 18:59, 26 May 2006 (UTC)

Coils are not typically called magnets, they're called coils. It can be either—the first is called multi-stage, and the second is called single-stage. [Mac Δαvιs] ❖ 08:38, 8 May 2007 (UTC)
I changed the word "magnet" to "coil" where appropriate. Have you got any reference to the multi-stage and single-stage terms? It would make a good addition to the article. --ZeroOne 22:02, 26 August 2006 (UTC)
Generally, it won't be either, it will be 2-3 coils at any given time, with the closest coil switched off just as the projectile reaches it and the next coil 2 or 3 down being switched on at the same time, in order to maintain continuous acceleration. Timing is also adjusted to account for the fact that it takes time (milliseconds) for power to stop flowing in the coil and the magnetic field to collapse - you want the field to collapse before the projectile passes the center of the coil, or else the coil then acts as a brake on the projectile, and throws the timing off on subsequent coils. From what I've read, the timing isn't as critical as it is with Gauss guns, however. -- Acehunter 20:30, 31 January 2007 (UTC)

advantage of coilgun over railgun[edit]

The 'Operation' section asserts that the coilgun can be made arbitrarily long, implying that a railgun cannot be arbitrarily long. Is this true? I don't see why a railgun of arbitrary length couldn't be made. Squiddy | (squirt ink?) 12:44, 5 July 2006 (UTC)

No one explained anything, so I just removed the section now. --ZeroOne 22:02, 26 August 2006 (UTC)
Railguns need to be short, because the power requirements increase with length. A long railgun requires very high current, which causes 2 major problems - erosion of the rails due to vaporization from the heating caused where the current passes from rail to payload (and from payload back to the other rail) and arcing between the rails from the voltage (higher voltages are required for greater acceleration - this is more of an issue in an atmosphere, and less so in space). Acehunter 20:35, 31 January 2007 (UTC)

I could add pictures[edit]

I did two science fair projects on coilguns... complete with animations of how they work... i'll add pictures when I get the chance. Blacklint 04:13, 25 July 2006 (UTC)

I just created an image (Image:Coilgun.png) using Blender. I take suggestions on how to improve it. However, I'd still like to see your images too, anyway. :) --ZeroOne 00:06, 25 August 2006 (UTC)
Great image, but isn't the coil usually a single continuous? How should we compromise coil density, with image prettyness? — [Mac Davis](talk) (SUPERDESK|Help me improve)03:39, 19 September 2006 (UTC)
You mean there would only be one single coil? I have never seen a reference to such a gun. I also think that the main point is illustrated best when the coils are simple — not overly long and not overly dense. And, oh, I replaced the static image with an animation. --ZeroOne (talk | @) 21:49, 16 October 2006 (UTC)

In Poential Uses[edit]

"A superconducting quench gun could be created by successively quenching a line of adjacent coaxial superconducting coils forming a gun barrel, generating a wave of magnetic field gradient travelling at any desired speed. A travelling superconducting coil can be made to ride this wave like a surfboard. " from "potential uses" is almosy identical to the "Superconducting quench gun" section at http://www.oz.net/~coilgun/theory/electroguns.htm —Preceding unsigned comment added by 68.35.19.109 (talkcontribs) 5 October 2006

Adding picture of a completed coilgun[edit]

Does anybody mind if I add a picture of completed coilgun? possibly:

single stage coil gun 1 or single stage coil gun 2

Lima-1 06:53, 27 December 2006 (UTC)Lima

Not at all as long as they are your own. --TTLLOGIC 01:48, 2 April 2007 (UTC)

reversing polarity?[edit]

is it possible to have a coilgun where the projectile is pushed instead of pulled? or both, so that the projectile is pulled towards the coils in front of it while being pushed away from the coils behind it? Skullers 18:39, 22 January 2007 (UTC)

-The idea of using the coils to push the projectile instead of pull it is interesting. I believe that it could work. But the effect of switching the polarity of the coils would not make much of a difference in the overall velocity of a projectile fired. Therefore it is possible, but not necessary. As to the idea of using alternating magnetic fields to "push" and "pull" a projectile simultaneously, the basic fact of magnetism is that opposites attract. So while it may seem that by "pushing" and "pulling" at the same time, you would increase a projectile’s velocity, the reality is that you would simply be creating conflicting magnetic fields. This would not only affect the path of the projectile in a negative way, but it would also put unnecessary strain on the coils themselves due to the fact that they would be constantly pulling on each other. So in the end, alternating the charge of the coils to “push” and “pull” would make it harder for the coil-gun to function. [(User: Crusnik 03)January 23, 2007]

  • It would only be possible to push a completely diamagnetic or paramagnetic material. Ferromagnetic materials can only be pulled in a solenoid.
Pushing is done, but it's unstable- the projectile tends to crash into the barrel. A combination of pushing and pulling is optimum, but you need more pull than push.- (User) WolfKeeper (Talk) 20:32, 6 February 2008 (UTC)

Need an article on Gauss guns[edit]

If someone has time, there needs to be an article on Gauss guns. I edited the coilgun page to reflect the difference between the two - they are not the same. Both weapons attract the payload, but Coilguns use solenoids and Gauss guns use electromagnets. See: This Page for details.

Someone would also need to edit the Magnetic_accelerator_gun disambiguation page.


Acehunter 20:20, 31 January 2007 (UTC)

Also, since there is a difference, why does "Gauss Gun" redirect to here? It makes no sense. O0drogue0o 11:12, 13 February 2007 (UTC)

http://en.wikipedia.org/wiki/Gauss_gun. Article must be redone.


Most people consider gauss guns to be the same. The more anal of the nomenclature fanatics want to limit it to metalic cores electromagnets exterior to the barrel as aposed to wound around it but that s like getting offended at calling a tissue a kleanex it just dosn't matter. They are synonamous. Finaly I am making a coil gun and have reserched them extensivly and I have never even heard of the above mention of a gauss gun: "they just fire focused bolts of EMP.". Like I said that just dosn't make sense but I would love to be proven wrong. Effilcdar 07:04, 18 April 2007 (UTC) p.s. reversing polarity is comon with permenant magnet projectiles. Effilcdar 07:04, 18 April 2007 (UTC)


And what would be this difference between solenoids and electromagnets? Solenoid by itself does nothing. Passing current through it would make it an electromagnet rendering the distinction pointless.

External links[edit]

I replaced the linkfarm with a link to DMOZ per spam concerns. Please discuss any additional links on this talk page, thanks. RJASE1 Talk 00:42, 15 April 2007 (UTC)

could you please add this link: http://www.wonkolabs.com/?page_id=22 I also filled out the "suggest a link" page.Wonkothe31337 05:07, 16 April 2007 (UTC)

Personaly I think that that is one of the worst posible pages to link to. Do not try the 4hv wiki that has a weak and much more assumptive article by individuals in their forum who never actually attempt but just type. Its just stupid to link to a page of links we have no control of just to make this article look more respectable. I am not sugesting that we add every site on the subject but lets face it, this is not the best article here and adding links to more extensive sites could improve the information gatering abilities of our readers. Thats the point of this site. You need to chose priorities of making this site BETTER than mainstreem encyclopedias or to make it LOOK better. Effilcdar 18:35, 24 April 2007 (UTC)

I'm going to have to agree with you. Every aspect of the article should be controlled by the users, and it's obvious that no one is keeping the dmoz updated because the links in this page aren't even being added. Additionally some of the links in that link directory aren't even about coil guns they are about rail guns.Wonkothe31337 19:05, 29 April 2007 (UTC)


I removed "The name Gauss gun is a reference to Carl Friedrich Gauss, who formulated mathematical descriptions of the absense of electromagnetic monopoles. Why Coilguns work according to the same magnetic principle as the Gauss gun, but their methods vary: both guns use an attractive magnetic force to accelerate the projectile, but Gauss guns use electromagnets while coilguns use solenoids.[1]" from this article, because it pertains to the guass gun, not the coil gun. It should be noted that Gauss's primary works described gravity and electromagnetic dipoles (and the lack of monopoles)... not magnetic flux. A different DWG described this, but Maxwell put it into a usful form.

Intro[edit]

A coil gun is NOT a -> "type of magnetic accelerator gun (MAG) or magnetic accelerator cannon (MAC)." Where did these terms come from? Google them. You can only find them in science fiction or from a few hobby websites. This does not belong here without some sort of reference.

I agree, they seem to be complete neologisms added by one user. The railgun article got rid of these a while ago, so I've changed the lead section to remove them. --Bob Mellish 09:27, 24 May 2007 (UTC)

Coil Gun/Gauss Gun[edit]

There's no difference between a Gauss or Coil gun. Saying the former uses an electromagnet whereas the latter uses a solenoid is analogous to saying one uses a pen while the other uses a Biro. The term electromagnet (IE pen) encompasses the term solenoid (IE Biro). A solenoid is a specific kind of electromagnet just as a Biro is a specific form of pen (as opposed to a fountain pen or quill et cetera). From wikipedia: "An electromagnet is a type of magnet in which the magnetic field is produced by the flow of an electric current" thus a solenoid is an electromagnet. Further down the page it gives a concise definition of solenoid: "A coil forming the shape of a straight tube (similar to a corkscrew) is called a solenoid; a solenoid that is bent so that the ends meet is a toroid." The trouble here is that the terms electromagnet and solenoid aren't well understood - and worse somewhat ambiguous. An inductor by the wikipedia definition can be a solenoid, as can a transformer winding. The difference is in their operation: an inductor is mostly used either to oppose changes in current, while a solenoid moves its own core. The electromagnets used in this manner (to move a ferromagnetic object) are solenoids.

If a Gauss gun used electromagnets in a different manner then they could be deemed separate, but both Coil gun and Gauss gun use electromagnets to attract a projectile for acceleration. There's no requirement that either type have this electromagnet mounted any specific way. There's no difference between the two I can see, so I'm editing the article to reflect that. 59.167.90.13 15:30, 28 September 2007 (UTC)

Exactly. It's the common linguistic issue that can be summed up like this: All solenoid are electromagnets, but not all electromagnets are solenoids. But quite frankly, whichever method they use it does the exact same thing in the same (general) way. Trying to make some false distinction between Gauss and Coil is like trying to argue that there is a technical difference between an essay written with a black bic pen and the exact same essay written with a black generic-store-brand pen. --Human.v2.0 01:21, 20 October 2007 (UTC)

I thought they were the same, but I just read an article that stated that a gauss gun actually has electromagnets at the end of the barrel, rather than wrapped around it, which pull the slug towards them before they are switched off and it flies out of the barrel. This may be wrong, and I agreed with you until 1 min ago, but that is what I have read. 213.78.183.91 (talk) 17:07, 3 March 2008 (UTC)

That definition simply makes Gauss Guns a particular form of coilgun. Whether you mount one at the end, or the middle, or any position along the barrel, it's still a coilgun. It's still a coilgun if you mount multiple coils along the barrel. To be a coilgun it has simply to be a device intended to accelerate a projectile using an attracting (or conceivably repelling) electromagnetic coil. If the 'gun' accelerated the projectile using an electromagnet that wasn't a coil one could argue that the gun technically isn't a [i]coil[/i]gun, but that's truly a semantic argument. By the definition you provide, which is unsourced and hence unusable, a Gauss Gun is a particular form of coilgun with the coil at the end of the barrel. If you source the definition and prove it's reasonably widespread in acceptance then add a section that notes the Gauss Gun is a particular planform of coilgun. Alternately you can get into deep semantics and argue that a Gauss Gun is separate if you use un-coiled electromagnets at the end of the weapon et cetera but does that achieve anything? 121.44.255.108 (talk) 15:28, 16 May 2008 (UTC)

Energy in the Magnetic field of the coil[edit]

I suggest that this section be removed. This is listed as a disadvantage, but usually the diodes that charge the capacitors completely prevent the inductor energy from charging the capacitor to a negative voltage. The energy circulates in the inductor coil and is dissipated in the coil resistance.

Problem with my coil gun[edit]

I have fired my coil gun a number of times, and here is what happens. The coil heats up so much that it melts the tape and plastic tube. I can't use an aluminum tube because of the Eddy current losses. Does anyone know a good solution for this? If so, it can be added to the construction section.

You can use aluminium if you slot it or laminate it.- (User) WolfKeeper (Talk) 20:35, 6 February 2008 (UTC)
Please, the talk page is not to be used as a forum. --75.187.254.159 (talk) 00:11, 18 February 2008 (UTC)

I thought about buying a ceramic tube for this purpose. It might be expensive, but I have heard they are available. —Preceding unsigned comment added by 76.99.35.150 (talk) 04:06, 1 August 2009 (UTC)

Link Spam?[edit]

I would like third party opinions on this link http://www.wonkolabs.com/?page_id=22 to know if it falls under parts 1, 4, and 12 of the links to be avoided sections in the wikipedia external links guide. The user who has been reposting the link is the owner of the website, it is a blog, the link also contains no information other then what is already in the wiki article. I feel the link should be reviewed by a third party before it can go back on the wiki article. I dont think it is very constructive to have a handfull of links that contribute nothing more to the article. --75.187.254.159 (talk) 11:58, 18 February 2008 (UTC)

I dont think the link is very helpful nor constructive, and yes it does fall under 1 4 and 12 as said. There is already links up that contain the same information, so why do we need another? --72.160.176.241 (talk) 12:05, 18 February 2008 (UTC)
amazing, an IP address that has no previous history with wikipedia, i'm sure it's not the same person :rolls eyes:
also, from what it looks like, almost every external link falls under 1, 4, and 12, why are you targetting this one specifically? Please read the coilgun history, it seems a while ago there was this same problem and it was decided that since most of the information about coil guns is from personal research then personal sites should also be accepted. I think the link contains useful information. —Preceding unsigned comment added by 207.62.164.9 (talk) 19:26, 18 February 2008 (UTC)
You are the site owner, please leave this to third partys to answer with a neutral point of view. Its also not a question of wether the information is useful or not, it is that the informations is already contained in the wiki and the other links that have been up before yours. Why is another link to the same stuff in a different font needed? --75.187.254.159 (talk) 01:06, 19 February 2008 (UTC)

External Links[edit]

Request to add or remove links here. Wonkothe31337 (talk) 21:05, 19 February 2008 (UTC)

so far it has been requested that http://www.wonkolabs.com/?page_id=22 be removed.
"I would like third party opinions on this link http://www.wonkolabs.com/?page_id=22 to know if it falls under parts 1, 4, and 12 of the links to be avoided sections in the wikipedia external links guide. The user who has been reposting the link is the owner of the website, it is a blog, the link also contains no information other then what is already in the wiki article. I feel the link should be reviewed by a third party before it can go back on the wiki article. I dont think it is very constructive to have a handfull of links that contribute nothing more to the article." —Preceding unsigned comment added by Wonkothe31337 (talkcontribs) 21:20, 19 February 2008 (UTC)
I believe that the link is useful and does add more aspects to the coil gun article. Also almost every link there is a personal blog and since the information in the wiki is based off of personal research this should be allowed. Even if it contains similar information it is still important to have since it's just more reference to the information, making it more reliable Wonkothe31337 (talk) 21:24, 19 February 2008 (UTC)
I replaced link farm with DMOZ --75.187.254.159 (talk) 09:59, 20 February 2008 (UTC)

Ive found these to be usefull sites: http://www.coilgun.info/about/home.htm http://rp181.110mb.com/ http://www.coilgun.eclipse.co.uk/ —Preceding unsigned comment added by 75.70.240.141 (talk) 17:32, 4 January 2009 (UTC)

Scope of the article[edit]

Ok, I think the scope of the article is real, engineering associated with projectile accelerators using contact-less magnetic means, with coils arranged along the barrel.

I've therefore removed all fictional references (which were invariably in-universe anyway) to a separate article which has been linked.- (User) WolfKeeper (Talk) 14:28, 26 June 2008 (UTC)

I'm considering moving the article to something like 'Coilgun (engineering)' to make this very explicit as well, to leave space for 'Coilgun (fiction)'.- (User) WolfKeeper (Talk) 14:32, 26 June 2008 (UTC)

It's fine where it is. The redir tag now explicitly mentions gauss guns, which should suffice. Chris Cunningham (not at work) - talk 16:44, 26 June 2008 (UTC)

Capacitor protection with diode[edit]

Shouldn't the diode be placed in series with the capacitor? Not across it's terminals. This will keep current from circulating backwards —Preceding unsigned comment added by 76.249.41.70 (talk) 23:31, 21 September 2008 (UTC)

Link[edit]

Perhaps include the links: http://www.gausspistol.com/index.html and http://www.coilgun.ru/ —Preceding unsigned comment added by 81.246.152.106 (talk) 17:20, 5 February 2009 (UTC)

Early (1919) reference[edit]

Proposed external link: http://books.google.com/books?id=7igDAAAAMBAJ&lpg=PA59&pg=PA18. It's an *early* reference in Popular Science Monthly, February 1919. The article itself would be useful for starting a "History" section. arielCo (talk) 21:40, 25 July 2009 (UTC)

Ferromagnetic projectile is not required[edit]

Once can construct a coilgun with an aluminum projectile. A current is induced in the projectile which the magnetic fields of the coil repel. see: Seog-Whan Kim; Hyun-Kyo Jung; Song-Yop Hahn, "Optimal design of multistage coilgun," Magnetics, IEEE Transactions on , vol.32, no.2, pp.505-508, Mar 1996 URL: http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=486539&isnumber=10395 —Preceding unsigned comment added by 134.134.139.73 (talk) 22:56, 10 February 2009 (UTC)

Magnetic saturation[edit]

The article currently says "One of the greatest limitations to the coil gun is the rate at which the ferromagnetic projectile becomes fully saturated by the magnetic field"

While this is surely a theoretical limiting factor and should be mentioned in the article, I'm very skeptical that magnetic saturation actually has much effect on real-world coil guns. You would need a HUGE flux density to saturate a projectile of any significant size. Can anyone provide any references to this actually being a problem in real-world devices? —Preceding unsigned comment added by 128.227.50.93 (talk) 16:28, 15 March 2009 (UTC)

Gauss Gun Confusion[edit]

If you go to Google and search "gauss gun" or "gauss rifle", most of the hits will be about a contraption made of metal balls and magnets, and uses magnetism and kinetic energy to launch one of the balls. What's the deal with this? —Preceding unsigned comment added by Kuhfelsen (talkcontribs) 20:15, 19 July 2009 (UTC)

Scale of force/speed achievable w/ household capacitors and materials?[edit]

The way this article reads right now, it is damn near impossible to tell if the homebaked rig described gets a sizable weight to Mach 10 or barely moves a metal shaving. Yes, I know wikipedia isn't a cookbook, but how about a sense of scale, people, SCALE! Could someone at least hint at what mass projectile could practically be accelerated to what speed with a properly built coilgun NOT utilizing expensive, specialist, or military hardware? What can a build using the suggested disposable camera parts hope to achieve? Now, if someone had a simple formula for approximating the results without a physics textbook, that'd be just superb... Aadieu (talk) 20:54, 9 February 2010 (UTC)

Differentiation between a coil gun and a railgun[edit]

I think it would be a good idea for a short discussion on how this is different from a railgun. The systems seem very similar, and to be frank, I don't even really see what the difference is (not saying there isn't one, just that I'm not learned enough in physics to understand it without having it spelled out, I have a feeling others are in the same boat as I).

Thanks

67.142.178.23 (talk) 04:23, 19 December 2011 (UTC)


Here is a basic defination for a Gauss/coil/quench gun and railgun:
---Gauss/coil/quench guns fire ammo that can be propelled totally by magnetism alone, either due to it being ferromagnetic (contains iron or another magnetically active metal) or induced magnetism (like copper or aluminium). The ammo can be a shell or solid. Quench Guns are the superconducting versions of a gauss/coil guns. Coil guns are named mainly for the exposed coils that most people see.
---Railguns are made with 2 rails and a sled (or shuttle). When a sizeable electric current is applied to the rails and conducted through the sled, a magnetic field is generated - pushing the sled forward (linear motor). Ammo rides on the sled and separates from sled at the end of the rails (either the sled drops away or is physically stopped). The ammo can be of a magnetic or non-magnetic nature (example: you could launch a clay pigeon with one). Railguns, due to their size/weight will most likely be vehicle mounted or stationary. — Preceding unsigned comment added by 184.2.41.65 (talk) 11:19, 27 January 2012 (UTC)

From a historic perspective, the terms "coil gun" and "quench gun" were both in use in the technical literature by the early 1990's. Personally, I first encountered the term "gauss gun" in the computer game "Half-life" but that, of course, does not prove that it was not at some stage coined for a technical use.Knobeeoldben (talk) 20:46, 10 December 2012 (UTC)

  1. ^ B. N. Turman and R. J. Kaye, EM Mortar Technology Development For Indirect Fire, Sandia National Laboratories, Albuquerque, NM, 87185-1182