Rail Gun

[HaRuMaN]

My group and I are doing a physics presentation on rail guns.  We are going to discuss the theory behind them (mainly Lorentz force) as well as some of the more common proplems (generating a large enough current or projectiles welding to the rails) involved with building them.

We are thinking about building a small working model.  Anyone ever tried this?  I have several ideas and want to bounce them off someone who may be knowledgeable on the subject.

[menace]

none--but make sure you get some good video cause I would love to see this.  Uber weapons always fascinate me (even though I know they are bad).

[PacManFan]

Rail guns are cool, and not that hard to build.

You'll need:

1) a copper tube
2) set of 10-20 coils along the length of the tube.
3) a magnetic or paramagnetic projectile (steel balls)
4) Capacitor banks
5) a scr - based triggering and sequencing mechanism.

The only real difficult part is the triggering and sequencing mechanism. You'll need something that can sequence the discharge of the capacitors into the coils in sequence from bottom to top at varying speeds.

Google for it.

-PMF

[SirPoonga]

Can you get the cool spiral effect that's on the quake rail gun?  
When you get this done post videos!

Menace, check this site out.
http://www.pipersprecisionproducts.com/

[menace]

Cannot find server or DNS Error  --i guess the site is down at the moment

[DYNAGOD]

theres a wealth of information on this subject online, i started and dropped a project a couple years ago on one and dont have any of the links i use to have (had tons of em).
the biggest problem is sequencing the pulses along the linear distance to avoid "suckback".
theres the potential to effectively "weld" your projectile to your rails if you dont have the timing correct.
this requires some fairly high end signal processing..
keep us up to date id love to see your project.

 

[bionicbadger]

Built one in high school (~15 years ago) for a special project in electronics class and show off at open house.  The gun was a glass tube about 3 1/2 feet long and around 1/4" around inside.  We used drill taps from a tap & die set as our ammo.  We only had 3 magnets, and 6 big capacitors (about 1 litre bottle size) 2 for each magnet.  It was controled through an RS-232 cable to a commodore PET computer where the timings could be adjusted in a small BASIC program.  It was fun.  If we got the timings just right (the "bullet" had to be placed exactly in the right position to begin with) we could embed the tap into a binder we had set up accross the table.

[rockhopper]

If i've read some of these posts correctly, except for Dynagod, the rest of you are talking about Coil guns not rail guns, they work slightly different.  Coil guns are just as cool though, and somewhat easier to make for the same effectiveness.