Homemade CD Shooter?

Rinisari asks: "I've recently come into a very large amount of defunct, yet still structurally intact, CDs. I did some searching about on Google, but turned up nothing on my goal: A Compact Disc Cannon. Has anyone ever built a device for shooting CDs in a horizontal or vertical fashion? I'm thinking almost something like one of those foam disc shooters..."

Comments

Uses for CDs

[mbstone]

The World Series of Poker on ESPN features a poker player who can slice a banana with a thrown playing card. Maybe you could try slicing a raw potato or other object in this manner with a CD. Then you could organize a contest and sell the TV rights.

Shazbot!

[Dfiant]

I was going to make a disc launcher a la Starsiege Tribes, but never took the time to find/make the proper gun structure. My idea was to cut the top off a CD-R spindle full of AOL CD's and mount it upside down on the gun so gravity would feed ammo into it.

What I'd have is a typical gun structure, but with a loading mechanism made to support stock spindles (of 25, 50, or perhaps even 100 CD's). When recoiled, the CD should fall into place onto a small bolt or something. The trigger would drive this bolt forward sharply along a rail by a spring or rubber band. At the end of the rail, the bolt would have to drop down so the CD can fly free of the mechanism. I hadn't put much thought into a semi-auto system, though.

Combo Railgun and Dremel

[R2.0]

I'm thinking the following:

1) Magazine feeds a CD to a dremel motor which spins the CD in place to about 5000 rpm. As it is spinning up, the...

2) capacitors in the railgun are charging. Since the disk has an aluminum layer, it should be able to be ejected from a railgun. So when the capacitors are charged...

3) a switch kills the dremel motor, which drops the disk into the railgun receiver. CD shoots off, rack another one into the spinner-upper.

4) Repeat.

Alternately, hack an old CD drive to spin and release the cd.

Re:Combo Railgun and Dremel

[dododge]

BTW: it's easy to demonstrate that aluminum and magnets can interact with each other.

Get a really, really strong magnet. For example a rare earth magnet from a hard drive head actuator (early 1990's drives with lots of platters are great for this). Then find something flat made of aluminum, such as a screen door. Place magnet on aluminum. As expected, it won't stick.

Now slide the magnet on the aluminum surface. If the magnet is strong enough, you'll feel it resist the movement. The faster you move it, the harder it'll resist. This should work just as well with copper and other non-ferrous metals. The motion of the magnet's field through the aluminum generates eddy currents (which other people have mentioned) and a corresponding magnetic field within the aluminum. Google for "magnetic braking" for real applications of this effect.

How you could use this to build a CD rail gun, however, I don't know.

1977 Ford F-100

[Piquan]

Stuck it under my tire and peeled out.

only 33 CD's?!!

[zcat_NZ]

I managed to collect just over a thousand CD's a few years back, well over 800 of them AOL CD's. This is quite an achievement given that AOL has no point of presence in New Zealand, so I have no idea why those CD's were here in the first place. I was planning to make a CD launcher using a pair of small rubber wheels, but in the end I gave the whole lot to a friend for part of an art project.

Rotational speed and linear velocity

[Tmack]

are what you need for a good CD launch. Without the CD spinning, it will just flop around and go nowhere. With a good spin on it, it will fly somewhat straight, with a slight curve to its flight path depending on launch angle. High linear speed will at least stretch that out if not eleminate it while on its way to the target.

My vision is of a CD spindle looking clip that loads the "ammo" from the top (gravity fed), with a bolt like thin sliding arm with a center spindle, to push the discs forward one at a time while holding the rest of the stack out of the way. When the trigger is pulled, the arm slides forward to launch a disc, and releases the next disc in the stack onto the top of the chamber. As the trigger is released the disc falls into the chamber where rotors on the sides of it, or the spindle on the arm spin the disc up to speed. When ready, the trigger is pulled, pushing the arm and spindle forward to the launching wheels. When the disc gets to the launching wheels, the spindle drops out of the way. The wheels themselves are rubber, touching each other, and spinning in opposite directions, such that when a disc is pushed into them, they spit it out rather quickly. They should be near the center of the disc on top and bottom of the track the disc slides on, offsetslighly to maintain the rotation on the disc itself, but keep the path of the disc somewhat straight out the end.

just a thought, dont look at me if you try to actually build somthing from this and hurtyourself.

tm

Think spinning tops, not frisbees.

[sakusha]

I can easily think of a mechanism to make this gadget work. Let me give you a few hints and you can work out the rest.

Think about tops, not disks. You guys are all thinking about spinning a CD down a slot. Instead, think of it as a spinning top revolving on its axis, like a CD is designed to do. Nothing says you can't modify the CD slightly. You could glue a small spindle into the center of the CD, or just cut a small slot in the edge of the center hole, so you can make a removable spindle with a keyed rod that goes in the slot to keep the CD from slipping.

So if you've understood what I'm getting at, you now have a CD with a little wooden spindle sticking up from the top and bottom. Essentially you now have a very thin, wide top. It used to be fairly common to have wooden top "launchers" or "brackets" with notches that held the top and bottom spindle on a top. In this case, you'd need a piece of wood about an inch thick and about 1 foot long. Cut a slot down the center of the wood to allow the CD to pass through. Cut a V shaped notch across the end of the stick, perpendicular to the slot.

Now you can set the spindle of the "CD top" in the notch. Wrap some string around the spindle, pull, and you've got the CD spinning at high RPM. flick the rod and your CD is flying.

I looked around the web and this page is about as close as I came to finding a top bracket.

http://www.turnertoys.com/tops4_toddlers.htm

You can kind of see what I'm getting at, but this version just drops the top down, it's not intended for tossing, and the plane of the top isn't centered in the bracket, it's below. But I think you'll get the idea. Now go build it..

Old skewl

[billcopc]

Call me hardcore, I remember a little Ninja Turtles toy that did just this, but with smaller, pizza-colored hard plastic discs that hurt like @*#^$. I think it used small motors to spin and launch the discs because the pizza thingies would fly everywhere, bouncing off walls/expensive vases/my forehead. Now those things were about 2" wide, and 1/8" thick, so they were relatively "dull". If you did this with CDs, I think it would be a safety risk because CDs are thinner, thus "sharper" and lighter so they fly faster and farther and dig deeper into your victim's skin if properly aimed.

Re:Easy

[denis-The-menace]

This DOES work!
I had a CD-ROM burner do this to me 6-7 years ago.
I has 12" away from the drive and it nearly got me.
The tray openned and the disk was spinning and bumping inside the tray like it was about to explode. It eventually hit one of the disc stoppers on the tray and that made it fly up and away. The wall behind me stop it, otherwise the 5 1/4" spinning ginsu would have done a lot of damage.

What about the Ripper from UT?

[DiscoSnorlax]

http://www.unrealtournament.com/utgoty/weapon_prof ile.php?weapon=ripper

Pitching Machine

[nuxx]

You mean something like Survival Research Labs' Pitching Machine?

This thing shoots 6' long 2x4's at over 120mph using the same concept... Except using tires and a 500 cubic inch engine. :D

Re:super dangerous

[Johnathon_Dough]

You could take the potato cannon method a step further (and dangerouser) Use propane instead of compressed air, create a decent launch tube for a cd with a small rubber seal, add an igniter at the end of the barrel...and weeee flaming cds. One solenoid valve, some 300psi tubing, a 12 volt battery, a few wires and a momentary switch.

I wonder if wrapping a few turns of gauze over the cd would get you both the surface area and seal you need for a compressed air release? It is amazing what 200 psi will get you in velocity.p. Using propane and kerosene soaked tennis balls, you can get a spectacular show...warning...big flat non flammable area highly reccomended.

70's Toy Disk Shooter

[JoeCommodore]

There was an old toy I had when I was a kid (70s), it held a stack of yellow plastic disks (about 3" diamter) in a drop load cylindar. You pull back a rubber band lever which dropped the bottom disk into a disk sized rectangular barrel under the cylindar, releasing the lever snaps it back - the disk pushing part of the lever mechanism was curved in a way so as it went back it spun the disc as it forced the disk out the barrel. Could probably de done with CDs with a bit more percision design work.

Another cool feature was at the top of the ammo cylindar was a rectangular funnel so you could theoretically catch disks shot at you and they would be back ready to be shot back.

I looked for a picture but I couldn't find one on-line, though I am sure I've seen smaller versions in the cheap-toy section of places like Target or Wal-Mart.