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Lateral Induction Launcher

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Chris

Wed May 31 2006, 01:17AM

Registered Member #8 Joined: Thu Feb 02 2006, 04:34AM
Location: Harlowton, MT, United States
Posts: 214

Did Chris ever finish his project?

Sort of. I have fired it several times, but never at full power, and I got bored and started to work on other things before ever firing the second stage. There are plenty of construction pics here

if this helps. Also there are some documents out there on a similar device built by Sandia Labs.

but I do have steel which I could use as the "barrel"

You'd better slot that, or you will have constructed little more than a pulsed induction heater. You're probably better off supporting the coils from behind anyway, for example my coils were designed to withstand something like 10 tons of attractive force, the extrapolated peak force when fired at full power. You'll be hard pressed to support that with any reasonably thin material in between. Maybe you could try some sort of ferrous core structure that surrounds a coil of any shape, like some kind of large bobbin.

FastMHz

Wed May 31 2006, 01:59AM

Registered Member #179 Joined: Thu Feb 16 2006, 02:08AM
Location: Hagerstown, Maryland - Close to Prime Outlets
Posts: 287

I love the hi-res pics! You have a well designed unit there...don't know how anyone could get bored with that

Looks like your platters were being destroyed...maybe too much energy? Mine is only 3.5kj so nowhere near as powerful...

Quantum Singularity

Wed May 31 2006, 02:02AM

Registered Member #158 Joined: Sun Feb 12 2006, 09:53PM
Location: Central Ohio
Posts: 282

Chris... wow it looks like you really put some work into that one. So you didnt ever get the 2nd stage working, thats a bummer. When your trying to switch this much power the multi stage idea becomes a bit harder.

One thing I have learned in this thread that I overlooked originally is the attractive force between the coils. That could doom my large scale version. But a smaller 'lytic powered version should be do-able. I guess my maxwells will have to stick to the vertically launched disk. I am curious though as to when this attractive force peaks. I am wondering if it will try to pinch the disk as it exits or assuming maybe the disk exits before peak power is reached, if most of the pinching action will occur after the projectile is clear? If that is the case then perhaps the launcher could be designed with a certain amount of flex to allow the coils to come together the 1/8" or whatever airgap is left after the disk vacates? If allowed to come together, even using 1/8" lexan under each coil will form a 'solid' piece of lexan between the coils 1/4" thick and I havent run the nbumbers but I would assume that should stand up to a few tons of force over a circular area 3.5"-5" in diameter?

To spin the disc I would use a little blob of adhesive to hold a center bearing between the coils, and use a friction drive motor to spin the disc via the outside of the ring...so it should be spinning, and upon firing the coils, the glue gives away and the spinning disc of death goes flying

I was thinking simpler like designing the 'barrel' to have a grippy material like rubber along one side (just on the very edge) and a smooth polished surface on the other. But like you said, spinning isnt high on the list.

My original idea was: low powered benchtop prototype using laptop hardrive platter (2.5") and a few hundred joules max (lytic) to perform tests and get some data. Then a higher powered 'fieldable' riffle model using maybe a couple kJ worth of lytics and 3.5" or 5" hardrive platters. Once I determined the forces at play with a couple kJ, then to design one using my larger energy discharge caps and either the 5" platter or a custom 1/4" thick aluminum platter. I guess I'll start from the bottom and work up (in terms of size and energy, that is).

Wilson

Wed May 31 2006, 04:37AM

Registered Member #78 Joined: Thu Feb 09 2006, 11:27AM
Location: Sydney, Australia
Posts: 133

hehe ^^ this is all very interesting indeed.
All the best of luck quantum singularity.

btw, i might join you soon in doing some induction launcher testing ;)
Almost finished an enclosure for my 2.8kJ lytic bank. Just need to wait for the end of exams before i can do some more tests

Plasmaniac

Wed May 31 2006, 12:52PM

Registered Member #206 Joined: Sat Feb 18 2006, 03:17PM
Location:
Posts: 72

Do you use aluminium busbars? I had some problems with aluminium on my 2kJ bank.

Wilson

Wed May 31 2006, 02:18PM

Registered Member #78 Joined: Thu Feb 09 2006, 11:27AM
Location: Sydney, Australia
Posts: 133

well i use Al. I've tested it to be OK up to 1kJ. Haven't went higher yet.
Copper would probably be preferrably, since its resistance is like 1/2 that of Al, but Al is just so much cheaper...

FastMHz

Fri Jun 02 2006, 05:36PM

Registered Member #179 Joined: Thu Feb 16 2006, 02:08AM
Location: Hagerstown, Maryland - Close to Prime Outlets
Posts: 287

I just finished my prototype and it works rather well. Starting position of the disc seems to be critical. I'm certainly not getting anywhere near the output power I was with my standard ILs, some of that is due to the disc being 1/4" away from the coil instead of right against it. I'll do some chrono tests in a bit.

Maz

Sat Jun 03 2006, 01:52AM

Registered Member #111 Joined: Fri Feb 10 2006, 01:04AM
Location: Menasha,Wisconsin
Posts: 65

Looks good!, do you think there would be much of a benifit to making the coils closer to the disk?

Wilson

Sat Jun 03 2006, 04:14AM

Registered Member #78 Joined: Thu Feb 09 2006, 11:27AM
Location: Sydney, Australia
Posts: 133

wow, looking good. Any construction details? It looked like epoxy and wood to me.

FastMHz

Sat Jun 03 2006, 05:46PM

Registered Member #179 Joined: Thu Feb 16 2006, 02:08AM
Location: Hagerstown, Maryland - Close to Prime Outlets
Posts: 287

Bad news - one of the coils got destroyed when I fired it at 3.5kj. The attractive force just sucked the copper right off the epoxy & wood block...

I'm sure it would work much better without the gap, but I don't have a material thin enough that can withstand the force...seem's my 1/4" hardboard flexed too much and allowed the one coil to destroy itself. I will probably abandon this prototype as I see no future for it if I can't fire it at full power. Time for a new design that I have the material to actually make...

I do know that the disc came out with enough force to seriously injure a person standing in the way, but I have no idea what the energy output really was.

This version was made of MDF, hardboard and plywood. The materals weren't damaged, but they flexed too much.

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