who is bored and wants to make an energy weapon with me?

[314159]

i was thinking something like a coil gun.

[Butterfingers]

Re: who is bored and wants to make an energy weapon with me?

Funny you mention that. Random thoughts wandered into my head about making a "battery cube"

10 stacks in series of 100 1000(ca) rated car batteries hooked in paralell.

Can provide 120 volts @ an output of 100,000 amperes for 30 seconds.

Enough power for a coil gun...

[314159]

the idea of a coil gun is that you want to shut the coil off when the projectile is half way through the coil. because the coil will want to keep the projectile in the center of the coil. rail guns are popular, because they accelerate the projectile along the entire lenght of the rails.

/me is now accepting capacitor donations to form a large capacator bank

[Butterfingers]

Originally posted by 314159

/me is now accepting capacitor donations to form a large capacator bank

Bah all you will need is the sunday new york times, lots of aluminum foil, and a crapload of gluestick :)

[314159]

butterfingers, i will be your friend if you make friends with the local photoshops and harvest disposable cameras for me

[bjjb99]

Originally posted by 314159
the idea of a coil gun is that you want to shut the coil off when the projectile is half way through the coil. because the coil will want to keep the projectile in the center of the coil. rail guns are popular, because they accelerate the projectile along the entire lenght of the rails.

Use a cascaded series of coils down the length of the barrel to provide additional "kicks" to the projectile. Get the timing right and you can do some scary things.

We had a home-brew single stage coil-based launcher in the physics lab back in the early 1990s. It consisted of several pieces of steel re-bar stuffed into a PVC pipe; one end of the pipe had many windings of heavy gauge wire wrapped around it. The power source was a capacitor bank originally intended for a pulsed ruby-rod laser. The projectiles consisted of copper rings (same material as the coil windings) about 2.5 inches in diameter.

Some rings were coated in superconductive material. Dunk one of those suckers in liquid nitrogen, and when it's cool slide it down the PVC until it was resting on the coil. A good shot from that arrangement would put dents in a lead target and take chips out of plywood. Not bad for home-brew.

BJJB

[synreal]

nothing spells fun quite like a homemade gauss rifle

http://www.powerlabs.org/multistagecg.htm

[SSMercury]

you people...are scaring me.

Although, firing a supersonic projectile with 3 times the ENERGY input of a sniper rifle does give me interesting ideas. Especialy when the whole arrangement weighs 33 pounds and measures 1.3 meters long. That's a pretty small linear accelerator if you ask me.

[314159]

*note: for educational and/or entertainment purposes only


entertainment..... yeah.... that's it >=]

[SSMercury]

Terribly inefficient though. I'm not sure what his efficiency is, but if he's talking 3-4% to work with, he needs to get it up. If he could get his efficiency up to 30-40% somehow, I think he might have a military application. He could make millions. Or have his equipment confiscated.

[xatle]

the multistage coil gun i never got around to building.

timing.
i was gonna use cascading 555 chips with trim pots for fine tuning to control the pulse timeing of each coil (555's are easy enough for a regular guy like me to figure out).

the barrel.
i never decided on what would be best to use for a barrel, since if it was metal it couldnt be magnetic, and if it was conductive it would need a split down the length of it to keep it from acting like a reducing transformer, glass would be too week to deal with the amount of torque caused by imperfections in the projectile and the coils.

the coils.
i was going to start at the dangerous end of the barrel and wrap 3 layers of 14 gauge magnet wire 1 wrap wide with the leads exposed, glue it in place with wax paper and a washer to keep its form while it dries, then remove the washer. i would repeat this for about 1 inch, then i would get out some 18 gauge wire and do the same for about an inch and a half adding more layers to keep the OD of all the coils fairly uniform, then 22 gauge for 2 inches. the idea was that whenever a wrap in the coil reached the halfway point in the projectile it would begine useing precious power to hinder progress instead of help it, so the ability to power down each wrap individually seemed like the only way to go if you wanted to achieve any sort of efficiency. electromagnets have a power up time and a power down time based on the inductance of the coil, so in order to get the most from your coils you need to keep the inductance low so that you can minimize the amount of time it takes to bring each coil to full strength as well as the time it takes to power it down. this is why i planned to use thinner gauge wire at the start and gradually use fatter wire as i progressed down the barrel.