I make coilguns and railguns a lot, it is my hobby. My best coilguns results were sending a 6mm steel slingshot pellet 40 yards at 45 degree angle, with 21.6 J input. My best railgun results were 5 feet horizontally, with 5.4 joule input.

I want to know if you build these, and how yours did. It'd be cool if you posted pics too

Do you have any pictures of your projects for us to take a look at ?

I want to get into them but I don't really have the time. I read though that if you make a railgun with 6m and put 6.5million amps through it, you can shoot a 2kg slug at 4km/s

Originally posted by llama009
I want to get into them but I don't really have the time. I read though that if you make a railgun with 6m and put 6.5million amps through it, you can shoot a 2kg slug at 4km/s

yes with 6M rails you can get it up to 4KM/S that is the current record.

My daughter and I have made some small ones for her science class. We had a class on magnitism ( I homeschool her ) and we built a passive ont that doesnt need juice. I did this with a yard stick, but you can use a ruler too. First, go buy (if your using a ruler) 1 inch cube magnets, and 9 3/8 ball bearings (steel). Next, secure the magnets equidistance apartallowing yourself 1 and a half inches at the beginning of the ruler, and 1 inch at the end of the ruler. I used strips of ductape and wrapped the tape arond the top of the magnet to the bottom of the ruler. Here is what it should look like with bearings in place. (O) is Bearings, (X) is magnets.

XOO XOO XOO XOO


You will notice that I only have 8 ball bearings represented above. The one that is left over is your firing mechanism. At the 1 and a half inch side, give the ball bearing a little force and send it down the groove in the ruler. The force from the BB hitting the magnet is transfered to the outside of the next pair. The reaction keeps happenning untill the last one is released. At that time, you have gained about 4 kenetic units over the initial force of impact.

I have made the small one with a ruler punch through thin cardboard at 1 foot. The yard stick will send a Ball bearing through a car windshield

Yeah, those are sorta cool, even though they aren't real electromagnetic guns. However, you can't obtain very high velocity as it will shatter the magnets. My 200 joule gun will send a ball bearing through a bunch of tin cans when (if) I finish.

Originally posted by DanD9
Yeah, those are sorta cool, even though they aren't real electromagnetic guns. However, you can't obtain very high velocity as it will shatter the magnets.

Only if you use ceramic magnets. You can buy 1 inch cube magnets that are VERY durable. I believe thay are magnetized steel(?) Not sure though. I know they are much heavier than ceramic magnets.

You are right about the steel magnets being capable of higher velocity, but a fast ball bearing will demagnetze the magnets by impact. So the magnets will be one use only . Well, I might be making a 1.6 KJ cap bank, so I should get real nice results.

Have any good links on the net for construction info?

Originally posted by DanD9
You are right about the steel magnets being capable of higher velocity, but a fast ball bearing will demagnetze the magnets by impact. So the magnets will be one use only . Well, I might be making a 1.6 KJ cap bank, so I should get real nice results.

Good point They do loose the intensity of magnetic attraction over time, but you still get to play a while before that happens. What suprised me is that the ducttape hel on the last three magnets I had on the yard stick. My daughter and I fired it about 20 times and only had about a 25% drop in fireing velocity.

By the way, is that you in the video? How old are you? I dont mean any offence, its just good to see young minds so imaginative.

Originally posted by DanD9
I turn 14 on the 24th Nov, so I am still 13. I've been doing this since april.

What is your electronic background? Have you had someone teach you, or do you read every book you can get your hands on? You seem to have a good knowledge of electricity for someone that is just turning 14. Keep it up, that knowledge will take you places

I suppose I will try your method again Kidfinger. Mind telling me where you got your magnets?

Radio Shack It has ALL my electronic needs They can order them for you if they dont have any. They ordered mine and it took about a week to get them.

[edit on 11/21/04 by Kidfinger]

Thanks! Yeah, I just read every book and website I could. Mind telling me about your magnets at all?

Electronics is fun, especially when it involves high voltages or currents.

Look up I edited my post for thi info on the magnets.

Alright, thanks. I will make a single use one with like a hundred stages
Ok, maybe I will just go for the highest power that is practical. Again, thanks.