Planning Summer Project - Multi-stage Coil gun

I wouldn't worry about getting supersonic. Just create someting that works. You probably should use a PVC or clear PETG barrel like we use for accurizing Nerf guns. I would think a metal barrel would accumulate some of the magnetic charge. If you use the clear PETG acrylic you can even see the projectile move.

Too early to think much right now. Just got up and no food makes john a sloppy thinker.

john

 

Well after doing some thinking i am going to try to see if once i draw up a plan for the gun and a "research hypothesis" if the college of engineering I am apart of wont help me with some of the things if i turn this into a research project.

 

you could just super-size that gauss pistol and have it throw a .223
but steel bearings would be a much better choice
btw
its getting $$$$$$$ to have any fun with it
i.e. lots of ammo!

 

And that is my shortfall right now. I just purchased a house, have college expenses and i wont be able to work until the 26th of june. Once july hits though I will be earning enough to allow me to begin building this.

 

Well after doing some more online digging around, I have decided I am going to start the design phase this next week. The Design phase 1 will incorporate the main chassis of the gun with room for the capacitors, barrel, and the magazine system. This will all be done in Inventor 2010 and I will post pictures of the 3d models as well as the multi-views of the parts.

 

i hear you on the $$$ shortfall brother
the dollar needs to go further IMHO!

 

I guess it helps when you have someone that works at the National High magnetic field lab. I am going to call him up and see if i can get some parts from them that they no longer use.

Also I have some ideas about increasing the efficiency of the gun but I am still finalizing those ideas into something tangible.

 

small cylinders of iron bar would be much better at utilising the energy of the magnetic field than steel BBs. Cool project btw.

 

Other source of amunition

while i have been watching this thread, it occured to me there is a ready source of ball bearings available, without tearing about usable bearings.

http://www.naturestapestry.com/magz.html

is an example of a toy construction thing that uses steel balls and magnetic sticks, you could use those balls for ammo, they are quite a bit larger than a steel BB


Just an idea


Nanosec

 

Thanks for the ideas everyone!

I have now started 3D CAD modeling so As soon as I get some of the components done I will post pics.

 

Cylinders, because of their length tend to be problematic in coil weapons. The length of the cylinder requires a longer 'ON' time to pass the coil. Remember we need to turn off a coil when one projectile has passed and activate the next coil to attract it. It appears that spheres - being the same length as 'caliber' are easier to calculate for.

john

 

Actually the problem with cylinders also falls heavily with the suck-back effect and timings. However, spheres have the problem of being hard to load into the mechanism and getting enough magnetic pull to accelerate it. The design I have in mind uses cylindrical projectiles and a small electromagnet to hold the projectile in place until the gun is fired at which point it shuts off and the projectile is moved through the barrel with the main capacitor bank discharge. The only problem then as mentioned above is the timings and suck-back effect.

 

Small update,

I almost have the magazine assembly complete. I have the side capacitor bank holders created and am working on the main part of the gun with the barrel and the bottom capacitor bank. I will post some pics this week of the CAD work.

 

i was reading somewhere that it is more efficient for the projectile to be already moving before it is accelerated, where someone used pneumatics to move the projectile before it entered the actual coil

 

Most rail drivers use compressed air to accelerate the projectile onto the rails.

 

There's some good information here:

http://powerlabs.org/emguns.htm

 

This really needs some pictures..

 

@ Oreon & capn pedro: I never thought of using that idea from the railguns and incorporating it into a coil gun. I will definitely have a look at how to integrate it into the design

@ hitman: that is the exact site I have been using

@Spaceraver: pics are on the way be patient.

 

If you decide to use HPA/Nitrogen/CO₂, shout up as I'm a PTI certified airsmith. I've rebuilt a fair few HPA regulators and can fix most paintball markers. The principle's the same I would imagine.

 

Ok thanks

If I can incorporate it i would be using CO2 because they come in the nifty little containers and probably something a long the lines of a paintball mechanism.