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Put enough current/voltage through anything and it can/will explode. a watermellon for example. Also look up exploding wire on youtube. People dump enough current through a bit of wire and it makes a nice little pop.

Just from first glance I think there may be some plans linked from the summary. Also (I have no association with either site and have NO idea of the reputation of either, I have just seen them referenced frequently on other sites)...

http://powerlabs.org/ has a picture of a microwave gun on their front page
http://www.plans-kits.com/kits.html They claim to sell 25kw-200kw magnetrons as well as kits

You're not likely to see 30k RPM drives any time soon. The speed of a 15k drive means that the outer edge of the 3 1/2" drive is spinning pretty fast... getting close to the speed of sound ...It's why CDROM speeds haven't gone up much since the old day of 52x...

Perhaps I haven't taken a math class in a while, but my cocktail napkin calculation says that a 3.5 inch disc spinning at 15,000 times per minute will travel just over 156 miles/hour. No where near 761 mph (speed of sound).

3.5 x Pi = 11 inch circumference x 15000 = 164,933 inches per minute / 12 inches / 5280 feet/mile * 60 minutes/hour = 156 mph.

Furthermore, while I don't argue your point that they are spinning pretty fast, I disagree with your assertion that CDROM's haven't increased because of this. More like, I believe CDROMs are simply not manufactured within sufficient tolerances, as indicated by their frequent vibrations when they spin up, and such vibrations could cause them to shatter.

For amusement: http://www.powerlabs.org/cdexplode.htm

Ok, this is great, but how fast can you spin them before they explode?

From: PowerLabs

A standard compact disk has a diameter of 12cm. If this disk is to spin at 35000RPM, the peripheral velocity at the edges of the disk (.377m circumference x 583.3 turns per second) will near 220m/s, or 722fps, or 792km/h or 492miles per hour

-fire

The Office XP disc which came with my laptop a few years ago, would be incredibly loud compared to other discs, and the entire laptop would shake. (I don't understand why and I can't figure out how a particular disc would behave like that)

Sometimes their lopsided labels throws them out of balance, and they do spin very fast, as I'm sure you are aware. Many HP disks are just as bad. I usually copy the CD to the hard drive and install from there when I can. The less time my machine spends spinning the disk up and down, the better. I'm sure it's easier on the drive also.

Design an 8 cylinder internal combustion engine where each cylinder wall is the stator of an electric generator, and the pistons are the rotor. Deceleration of the massive piston (in comparison to the projectile) would generate a current spike onto the railgun rail. Still not enough? Use really massive pistons and a higher compression. Still not enough? Use a flywheel to store the energy.
The energy density of a flywheel is significantly higher than a capacitor bank and there are fewer energy losses.

The point is, if the induction pulse can be shaped correctly, it's not necessary to store the energy electrically.

Think of it as an energy conversion problem:

How much kinetic energy does one piston in an internal combustion engine contain:

From http://www.flatlanderracing.com/jechrys-sbft.html
Piston weighs 489 grams (1.08 lbs) stroke = 4"
Assuming 5500 RPM (181 trips up and down per second), pistons max speed is
181 trips/sec * pi * 4" stroke = 2298 in/sec = 191 feet/sec

From http://www.chuckhawks.com/rifle_ballistics_table.htm .308 Win. (150 Sp) has 2820fps and 2648 foot pounds of energy
e = mv^2 so projectile weight = .0003 lbs
The 1.08lb piston would need to move (2648 = 1.08 * v^2) or v = 49 feet/sec to have as much energy.

As you can see, one one pound piston in an engine running at 5500 RPM contains almost 4 times as much kinetic energy as a .308 round. The engine would stall if you tried to extract that much energy however:

The power output of a chrysler slant 6 engine is 134kw (mere 180 hp), power in watts of a 308 round is 3590 watt seconds.

Assuming railgun efficiency of 47%, energy extraction from the flywheel efficiency of 70% = 32%, you should be able to fire ((134/3.59)*.32)=11 rounds per second.

As far as the heating problem goes, pumped liquid nitrogen or water coolant + Gatling configuration should be close.

(Note: I mixed and matched some of the cylinder/engine figures, I couldn't find the information I needed tied to the same engine.)

Another cool Railgun link:
http://www.powerlabs.org/railgun2.htm

Yeah, but they seem to explode when I use my dremel to spin them

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

Here is a rail gun design that fires ~30 shots before the rails need to be serviced. It packs less of a punch and it's a lot smaller than the full scale rail guns that will be in testing by June. I can't imagne for the life of me why the military would build full size models for testing without working more on solving the problem of friction.

Has anyone else found out about these guys?

It's an old site but it's still just as awesome. I almost considered trying this out myself but I'm not exactly sure if such a thing is legal.

This fellow has been at it for some time:

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

I'm looking forward to seeing the details on his latest 2kW microwave gun:
http://www.powerlabs.org/images/uwhorn.jpg (full page not up yet)

http://www.powerlabs.org/

Interesting guy.

This fellow has been at it for some time:

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

I'm looking forward to seeing the details on his latest 2kW microwave gun:
http://www.powerlabs.org/images/uwhorn.jpg (full page not up yet)

http://www.powerlabs.org/

Interesting guy.

This fellow has been at it for some time:

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

I'm looking forward to seeing the details on his latest 2kW microwave gun:
http://www.powerlabs.org/images/uwhorn.jpg (full page not up yet)

http://www.powerlabs.org/

Interesting guy.

The problem with capacitors is energy density. They can charge and discharge quickly, but the amount of energy per unit volume or per unit weight is usually not very good, even compared to batteries.

New supercapacitors (existing term, really) will improve the energy per weight or energy per volume, but they may cost more (energy per dollar).

If this is cheap and hig density, it could be a great step forward.

PS, check out the powerlabs guys. They do lots of dangerous stuff with bit caps
http://www.powerlabs.org/railgun.htm

Because the GNU/Linux community writes software in the general hope that others will find it useful. These companies (TFA not working - 'cyclic link found') are helping those whose stated agenda is to violate freedom of speech and doing it for a profit.

Comparing the OSS community to them is like comparing ChemLabs to an international arms dealer: Sure, you COULD use the information there to synthesize a dozen different explosives and toxins, but that's against the spirit and express intention of the page, and he won't help you with it. An arms dealer will sell you guns, bombs, and nerve gas, and show you exactly how to use them - just bring money.

Yes, but I've read that they aren't engineered to handle the stresses of a high-speed drive so I'd copy them to CD-Rs or the hard drive. I've used my original PS1 discs in my 24-speed drive with no problem (using ePSXe), but they could shatter in a 52-speed.

See cdexplode, at the bottom.

For example
Bert Hickman's coin shrinking
Thaltech's capacitor experiments
Sam Barros's Power Labs page
Bill Beaty's webpage
and many others...

Sure, was some kind of 'freudian' typo (maybe I was thinking about quake 3 when I wrote it).
I've read about a home-built railgun once ago here. BTW that guy is doing some other crazy stuff with large amounts of energy *g*.

The rail or e/m gun (whatever it was called) in the Schwarzenegger flick Eraser used electromagnetism beams/rays to accelerate projectiles at incredible speed. Check out http://www.powerlabs.org/emguns.htm

http://www.powerlabs.org/railgun2.htm sure, it's a bit expenseive, but hey, it works!

These guys beat them to it

This "new" approach of achieving fusion using strong electric fields is of much greater significance than just academic interest in fusion research. It may well lead directly to EM-pulse-based clean-fusion bombs that don't need a fallout-producing plutonium atomic-bomb trigger. There are a LOT of ways to produce REALLY strong electromagnetic fields for a fraction of a second and let's face it, many of these can be done in your basement. So...are homemade nukes closer as a result of this discovery?

Let's see your fancy "salt water" and "electricity" do this!

What if someone put a videocamera on a fast RC-model plane like http://www.powerlabs.org/images/planeandme.jpg
and flew over Area 51?

Should be able to get closer than Tikaboo Peak:
http://www.dreamlandresort.com/area51/panorama_090 1.html

Perhaps it would travel too fast for a good picture?

Ah... you're thinking of the perpetual /. favorite, Sam Barrios, of Powerlabs fame. Pics and video here.

Ah... you're thinking of the perpetual /. favorite, Sam Barrios, of Powerlabs fame. Pics and video here.

No need to bother yourself. This guy has already done it, and has videos of the results.

His page is full of all kinds of very cool, dangerous experiments.

Why not bring those CDs down to the wood shop and gather additional observations on the ability of CDs to handle speed? Its surely more amusing than building a bread box. And, with 115,241 observations, I'm pretty sure the central limit theorem will give you a more reliable sample estimate of the true failure point.

I wonder if your shop teach has the cojones ...

Why not bring those CDs down to the wood shop and gather additional observations on the ability of CDs to handle speed? Its surely more amusing than building a bread box. And, with 115,241 observations, I'm pretty sure the central limit theorem will give you a more reliable sample estimate of the true failure point.

I wonder if your shop teach has the cojones ...

Power Labs

Railgun project

Perhaps this will change your mind on the strength of polycarbonate.
Bear in mind that a CD at 52x spins at 10900rpm.
The old PS1 discs would sometimes explode. And not explode as in crack, explode as in cd-drive-faceplate-on-the-other-side-of-the-room.

if I have pipe, black powder, and manifestos about how certain places should be blown up....

Pipe.

The refrigerator water line broke a valve. I just replaced a bad faucet in the kitchen. My sewer line sprung a leak last month. The freshwater line is leaking this month. I've got spare plumbing parts lying all over the house, just trying to keep up with it all.

Black Powder.

So I'm into target shooting. Hey, geeks with guns, and all that... Ammo is expensive. Reloading cuts my costs in half. I've got top of the line ammo reloading gear. Liters of black powder. Hell, I've got boxes of fulminate based primers. (They come in lots of 1000 units.)

manifestos

After the Oklahoma City Bombing back in '95, I began to doubt our various news sources' accuracy/truthfulness. They didn't seem to be sticking too closely to the facts. So I bought some books, old army manuals really, on how to blow shit up. Improvised explosives, and how to use them. Sifted through the news reports for facts that were there. Ignored the obvious rants. And drew my own conclusions.

(FYI: I concluded the second seismic disturbance occurred from lateral displacement of a supporting column in the structure. When it broke, the energy released would have been like a second bomb going off. Neatly accounting for the asymmetrical damage. Thank god Timothy McVeigh was a such an incompetent bomber. Oh, and the feds were almost certainly responsible for burning those Davidians alive. The wind patterns. The holes punched by their tear-gas tank created a chimney effect. The pattern to the holes appears deliberate.)

about how certain places should be blown up.

I've been a long-time critic of airport security. It's just nuts. (I can't take a pair of nail clippers on. What's the rational there? If you don't let me hijack the plane, I'll trim my toenails? Or forcing women to drink their own breast milk?)

On the other hand, even with all the extra post-911 security, its still damn trivial to slip guns/knives/bombs through. Obvious security lapses that just aren't being patched.

I'd like to get them to change. Preferably without getting myself arrested in the process...

I'm just doomed, aren't I? But imagine if they raided Sam Barros' place!

P.S. As long as we're playing gestapo here, I hope you won't be put out about coming down to the station for some hard questioning, not to mention paying for a lawyer, for conspiracy to rape that girl out in Timbuktu. After all, you've got the equipment! We need to investigate...

...Is this really anonymous? If you don't hear back from me, its not...

Or Dremel

Mr. Tesla is one of the more underrated scientists of the 20th century. From his coil to his steam turbine (which goes fast enough to cause it to break apart under centrifical (or is it centrifugal? I can never remember the difference) force much like spinning a CD with a drill/Dremel. Speaking of which, the poster should check out Sam Barros' site, which shows his past experiments (most/all of which include technical information) You are bound to find something helpful/entertaining in there (like fun things you can do with an old microwave oven :) --Brendan Orr (after hitting the preview button and going to the site, I realized that Sam deals with mostly high-power [i.e. that could kill & fry you in under a fraction of a second], so it might not be too helpful, still fun to read.)

S-ATA seems to be the solution for the data transfers involved with 16x DVD recording and the fast 52x CD-RW drives. Did we forget that CDs tend to explode when spun up faster than 56x? That seems like a bigger problem than not having enough bandwidth to transfer data...

That is, in fact, faster than the fastest speeding bullet (how fast is a speeding bullet?) So what could you do with a vehicle that fast?

Actually it's not. There is a special projectile/gun type which can reach hypersonic speeds and that is the railgun (no joke). The difference is that the rail gun accelerates in vaccum by electormagnetic means and can easialy reach 5000+ MPh. The US army is experimenting with the thing (which is Huge if large speeds is to be attained) and are planning to build some sort of tank killer using just the kinetic kill principle.

For reference look Here or here

Yours Yazeran

Plan: To go to Mars one day with a hammer.

PowerLabs?.

See Sam Barros' Powerlabs for similar stuff - the guy has got a lot of very cool and realy interesting stuff.

Especially interesting are his high-voltage stuff.

See Sam Barros' Powerlabs for similar stuff - the guy has got a lot of very cool and realy interesting stuff.

Especially interesting are his high-voltage stuff.

Like this one, eh?

bit of shameless karmawhoring...
Powerlabs

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

That only works for Windows users. For Linux users, you sit at a root console and repeatedly type:

pppd call adsl

or, if you have a cable modem:

ifdown eth0 ; ifup eth0

If the modem isn't even working right, THAT'S when you consult the list. Especially the part about the AOL disk.

This guy has the right idea: http://www.powerlabs.org/cdexplode.htm

I posted earlier but it got modded down by some bitter asshole; I got kicked out of school 4 years ago for this right here which I wrote about a classmate (his website is here)

I got kicked out of school for making a webpage about a class mate who had his website here on slashdot once. I don't regret it because I still think it was totally hilarious and that he was a nerd, and that's what's really important to me.

But still neither are quite as cool as this Trebuchet from the which launched a piano and a cow.

Honestly? This sounds like a job for PowerLabs.

"Sex is no problem here," Holowaty said.

"But violence is very problematic."

This picture is great. The guy is sitting on the floor looking at a 35000 RPM CD which is most certainly going to explode, and wearing nothing but a pair of (what looks to be) sunglasses! He looks like a little kid whose found his first book of matches and is mesmerized by fire! I can't view the video (./'d) so I can't comment of his actual procedure, but from the looks of things he could have been in for a world of hurt. At 35000 RPM, that plastic might as well be concrete, or glass.