SpudFiles

I do admit that it's an interesting concept Rag, but I think that's all it will ever be. Not many people have access (or the wallet) to buy up a capacitor bank or the materials needed for construction. Sam Barros had many investors, including the military to build his Rail Gun and that uses enough electricity to run a small town. The concept is good, but quite impossible for any spudder to create for the purpose of shooting potatoes.
It's a shame that compressed air, combustion and a mix of the two are really the only three ways to propel spuds.

See the bottom link I stuffed up there to the Powerlabs electrothermal gun?

That is for all practical purposes a length of steel pipe and a car spark plug.

The xxKV capacitor charging and discharging circuit would be the most difficult to get parts for but it's not impossible and won't break the bank if sourced well.

My personal doubts don't fall on powerful plasma burst generation but the idea of manipulating it with magnetic fields. That will require some serious tech which I don't really think is feasible without serious co-op from your uni and probably funding.

wow that's some crazy stuff man and you're right spudding does need some innovation. keep us updated

I wonder if your uni could cooperate on this, and possibly provide funding? If you ever get some free time, I'd like to have a look at that magnetic guidance system of yours, if you actually have a full blown design for it.

It certainly would be nice to see a revolution in spudding. In all honesty, we will begin to reach the limits of what our current methods can do in a few years. The projects I'm working on may seem revolutionary to some people now, but they really do nothing other than increase the power, and optimise valve design. This design, while obviously not accesible to the average person, shows that there is still possibility of advancement. I wish you luck with it, if it ever gets to that stage.

Just wanted to throw something out there that may help (if you didn't already consider it)...

Coilguns need optical triggering to time the bank discharges right. Since plasma is a conductor, you can probably omit fancy optics and timers by just using the plasma to close the coil circuits as it travels down the barrel.


I'd just start with a plasma gun, then if that works consider adding a coil system to it. How big do you think your capacitor bank is gonna be? (or, in other words, do you think you're going to be moving this thing around, or is it gonna stay bolted to a table?)

With my comparitively miniscule knowledge of the subject, I'd be leaning towards the "bolted to a table" side. This would require some really serious capacitors to work.

http://4hv.org/e107_plugins/forum/forum ... .php?32933
24k J cap bank. He's designing it for a coilgun, but im sure it would work for plasma gun.

Warning, this post may make no sense. I am not drunk, just rather tired, and my trains of thought seem to be to failing me as I'm typi

Maxus, for now, you are right, it does remain a concept.

I personally want to go quite a bit further into the field of conventional gauss guns (or coilguns if you prefer. It's more correct, but gauss sounds cooler) because a decent gauss gun is easily within the reach of a spudder who's prepared to invest a little effort.

If you'll believe it, although people think of gauss guns as pretty wimpy, a completely self contained coilgun with a similar KE and a significantly higher ROF than an average airgun is within the reach of anyone who can demonstrate a modicum of skill at soldering. I'm planning to go and prove that, and make plans and diagrams at the same time so that others can follow.

That's all before I will start to work with plasma based prototypes, which are going to need some pretty serious thought, and as you yourself said (with a slight change on my part) are "quite impossible for many spudders to create".
I'm both pretty smart and a reasonable builder (not by any means to demean anyone else's intelligence and/or building skills), and even having conceived (at least in part) the idea, but were a zany millionaire to wander in right now and after explaining what he (or she, mustn't forget gender equality) were doing in my house, were to offer me as much money as I needed to try to create a working prototype, I'd still want at least a concentrated week or two over the drawing board and researching before I picked up any tools.

I know the idea isn't completely fleshed out, because I threw this idea out into the forum rather early in my thought process, but we are in the theory section after all, so it's appropriate.
However, it is still an idea that can be thought over for a while, and something may eventually come of it. Maybe it might inspire another idea that has greater merits than mine.

Still, it is not entirely impossible that the idea could possibly be worked on with my university, although I rather doubt it would be right now, it might be able to see the light of day at some date in the not too distant future, but I may want to come up with a different explanation, rather than "I want to make potatoes go very fast".

@DYI: I quite agree. Spudding can only go so far on current materials without launchers stretching limits so much they become dangerous, or becoming so large they are impractical, unless you start machining everything.
I'm perfectly happy to be running around building launchers with more pressure, better valves, and other such refinements, but I do recognise that won't go much further. You can't realistically use more than a few thousand psi, and most people can never go outside a few hundred. Spudding hasn't really gone that far since the hybrid, with a couple of small exceptions like the piston hybrid.

I haven't yet got any full plans for any single one part, but I will put together some stuff over the coming weeks, if I find the time.

@_Fnord: Interesting ideas... I hadn't thought about the conduction idea, but... I definitely will now, thanks.
And, I think that for a small design, the cap bank could possibly be semi-mobile, I still need to work out to what extent.

"Bolted to table" size banks contain more energy, and if something could potentially go completely wrong, which is not that unlikely with experimental stuff like this, that isn't going to be a good thing.

It's always worth following the three hazard locale commandments:

- Minimal presence: Only have as many people around any potential hazard (referred to as Y) as you have to have. If someone's there for no reason, they should be directed elsewhere.

- Minimal quantity: Don't use more than you need. If you only need X amount of hazard Y, get only X amount of Y, that way if it goes wrong, the results will be less severe.

- Minimal time: Only have Y around for as long as you need it. If you need Y in an hour, don't arrange for it to be around until then, then you have less time in which things can go wrong.

@rp181: Yes, I saw that (read those forums, don't post that often). 24kJ is a lot of energy - bear in mind energies as low as 16J can be fatal to many people. As I said above, using more energy than you absolutely need isn't advisable.

I'm not convinced that:

a) Coil guns are the way to sidestep construction strength limits on the power of a launcher... with a coil, you still have large forces involved. Not to mention the power switching circuitry.

b) Electro-thermal guns are the way to sidestep construction strength limits - you do get a slight benefit from be able to shape your electric pulse, but all that allows you to do is build a smaller launcher. (and with the required capacitor bank, that benefit goes away)

c) Your 3^nd concept is unique... indeed, it sounds like what happens inside a generic high-powered railgun.
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Electro-thermal guns are certainly a fun concept to fool around with, but I'm not certain that they have any practical application outside of pushing the velocity envelope (hotter gases).

How about a combustion or a hybrid cannon inside a microwave ?

Microwaves water, if you just put a gun in, all sharp points will ionize the air, and if there is nowhere for the energy to go, it is deflected back into the magnetron, and is destroyed.

Darn..I don't get plasma.
I was talking to my brother about creating plasma, as seen on youtube..

It is supposed to be the 4th state right..
Solid, fluid, gas then plasma.
I still would not know how to turn that into a weapon of some sort.

Fill your reservoir with plasma iso gas and what happens??
And hte big question is how does one achieve that??

Plasma is ionised gas. Basically the stuff a flame or a spark is made of.

The idea behind a electrothermal gun is you dump an enourmous capacitor through a spark gap in a barrel, thus very rapidly heating and increasing the pressure of the air inside.

Pressurised and heated air then blasts the projectile out.

so i'm not really experienced with plasma, i mean i have used a plasma cutter before but how would contain plasma until you needed to use it and how would you generate enough of it quickly to use as a high pressure source to propel a projectile

It's not like a pressurised gas to store until needed. In this case it's generated by a massive spark in a tube and that spark by itself heats and pressurises the air in the tube enough to propell the projectile.