What's the Coolest Thing You've Ever Built?

Josh Lindenmuth asks: "In high school I was involved in an engineering competition where we needed to create a machine that could move 100 lbs of groceries from a disabled person's car up and down a set of stairs, and then into their kitchen. It was probably the coolest thing I ever built (there were only 3 of us on the team), even though the wooden treads started splintering halfway up the stairs (we didn't have a metal shop, so it was made entirely out of wood, spare boat parts, and conveyor belts) and then it completely destroyed the stairs on its way down (it weighed over 300 lbs)." That's Josh's story, now he wants to know yours. Cool computers, cars, hovercraft, handheld devices, fusion reactors — what is the most interesting gadget, product, or device that you've ever built on your own?

My Son

[Anonymous Coward]

Period!

Re:My Son

[Anonymous Coward]

Mod parent up! HA HA! Really! Parent! Oh, pinch me!

Re:My Son

[Fulkkari]

Built? If you are the average Slashdotter, you merely did half of the design.

Although...

Getting that far can be already be seen as a great accomplishment over here. :-)

Re:

[Anonymous Coward]

If they are the avarage slashdoter, i think they did more then half, like all of it. Its no secret that its hard for us to find a partner to perform this activity, so, some rare slashdoters must have evolved to a point where they can do all the work themselfs. This is proof of evolution in action.

Re:My Son

[ettlz]

Actually, isn't the process a bit like building^Winstalling Gentoo?

Re:My Son

[quigonn]

That's right. Both take about 9 months to complete.

Reminds me of a joke

[kbielefe]

Maybe when DNA research advances, you can actually build your child.

That reminds me of a joke:

A scientist goes to God and says, "We don't need you anymore. I can create a human from nothing more than a handful of dust."

"Alright then, let's see," God replies.

"No problem," says the scientist, and he bends over to scoop up some dust.

"Hold on," God interrupts. "Get your own dust."

My Son My Period.

[Anonymous Coward]

You built a period into your son? How freudian of you. I hate to see what you put into your daughter.

Re:

[waterford0069]

At worst you provided half the design.

At best you provided half the design, the manufacturing space, the materials distribution chain, and the delivery system. Your son did the rest him self (which when you think about it is rather resourceful of him).

However, this being Slashdot - I'd bet on the former over the latter.

Re:My Son

[hotdiggitydawg]

Actually, as a theoretical worst-case he may have not even been the one who "put in the successful tender", and just been stuck with the rather lengthy maintenance contract.

Re:

[Paradise Pete]

My Son Period

With a name like that he's in for nothing but grief.

I gots you all beat

[Quiet_Desperation]

I built a reality simulator. You're living in it right now. Neat, huh?!

Re:I gots you all beat

[hotdiggitydawg]

No, it sux bigtime. The plot moves at a glacial pace. Why do you think we're always trying to escape it?

Dude ... the joke's on you.

[Savage-Rabbit]

I built a reality simulator. You're living in it right now. Neat, huh?!

Your self are living in one of my own collection of home built reality simulators. I'll give you credit for being the only one of my simulated worlds to develop a reality simulator inside your simulation.

Greetings,
Your Lord and Creator.

P.S. If you think that's strange you should see the 4D Holo-presentation I got the other day attatched to a subspace mail message. It's from a giant lizard like creature who claims that I am living on a planet in a miniature universe he carries in a little marble on his keychain....

Satellite Parts

[SirLoadALot]

When I was in high school, I built some parts for the temperature regulation system of the AMSAT Phase 3D satellite. 288 tiny aluminum parts, each about 2cm long, and 0.1mm tolerance on all measurements. We used the school's CNC milling machine, but I had to hand-write the CNC code to do the parts in four passes, because the CAD/CAM software wasn't up to it. We then we hand-polished the parts to get them within tolerance where possible. The satellite is still in orbit, it shows up in J-Track as Oscar 40, but apparently it doesn't work anymore.

Re:Satellite Parts

[fyngyrz]

That's really neat.

My "coolest" thing was related to ham radio also.

I came up with some ideas for a mix of hardware and software for the Amiga that would do SSTV, as well as a new SSTV mode that would provide a degree of noise resistance not present in then-current SSTV modes. Previously, I had written a PCB CAD system that did circuit trace layout. I designed a microprocessor-based board that would do the modulating and demodulating, but I didn't have a schematic capture system which I really wanted to use since I had seen them in magazines, so I wrote one and then used that. Then, when it came time to write the code for the CPU, I didn't have an assembler; so I wrote a cross-assembler for the Amiga. So that code had to be burned to the EPROM in the CPU; as it happened, I had worked for a company in Ft. Lauderdale and designed a burner for that CPU and I still had one of those, so I used that. I wrote the host program in C -- lucky me, I had the Lattice C compiler and 68000 assembler that came with the Amiga. :-)

What was cool about this, to me, is that I kind of picked myself up by my bootstraps almost every step of the way. The PCB design system and the schematic capture I wrote, the board I designed, the circuit I designed, the 68705 assembler I wrote, the code for the 68705 I wrote, the 68705 burner I designed, the C host code and all of it running an SSTV mode I designed... that is the most varied set of tasks I ever had to do for any one project and to this day I have one of those gadgets hanging on the wall to remind me that if you can't find what you need... you can do it yourself.

Eventually a HAM radio company (AEA) bought the design and it went on to do pretty well for the kind of widget it was. It was in the ARRL handbook for a while, might still be for all I know. It won technical achievement of the year at the Dayton hamfest, too, for the noise resistance. Almost everything about that project (except the FCC approval process) was fun. Although the device passed first time out, the bloody Amiga itself was noisy as hell; we just got in under the wire. That was my first real lesson on just how unreasonable and silly the FCC can be. Since then, I've learned... they're even worse than I thought. :)

Stealth Roach-Clip

[FatSean]

I had a fancy Williams-Sonoma aluminum cork screw and bottle opener. It was a flat oval and the end opposite the bottle opener hook split open like wings. The wings revealed a cork screw, which was yanked out of the gizmo the third time I opened a bottle with it.

So, a little epoxy and an old aligator clip...I have a stealth bottle-opener and roach clip.

Was also involved with 'Odyssey/Olympics of the Mind', but that was lame because every team had parental help and the money rules were shat upon constantly

Re:Stealth Roach-Clip

[itwerx]

Speaking of "re-use"...
      I built an entire assembly line with pick-and-place, SMT hot bar, etc for memory modules (single-sided only) out of parts from old printers, floppy drives, tape drives, typewriters, hard-drives, and assorted other junk. This was back in the early 90's when 72-pin modules first came out and were expensive as hell even though they weren't really any different technology than 30-pin. It only produced about 10 modules per hour (with frequent stops and starts for various reasons) at a time when commercial lines produced 50k an hour, but it worked dammit! :)

That one time

[pap3rw8]

There was that one time I built a machine that could propel cats to the moon. It almost worked, too.

Re:That one time

[ArsonSmith]

Is that why I found a dead cat in my back yard yesterday?

Re:That one time

[Savage-Rabbit]

Is that why I found a dead cat in my back yard yesterday?

That depends.... Was it wearing an astronaut's suit?

I hate to (have to) ask...

[davecrusoe]

but... how could a 300 pound machine completely destroy stairs... because of its weight? For what it's worth, I imagine that many of us weigh > 300 lbs when carrying our MASSIVE computers upstairs from the car... or 130 pounds of Ramen noodles... or about 60 of the lastest video games... or... well, you get the point.

Re:I hate to (have to) ask...

[setirw]

I think many /. readers weigh >300lbs, period.

Re:

[stevo3232]

It's all in how it's going down the stairs. A 300 pound person walking down the stairs and barrelling down the stairs are two different things.

Re:I hate to (have to) ask...

[Anonymous Coward]

Feet tend to distribute wait in a nice, convenient way. That, added to the fact that muscles allow us to slowly descend our feet to contact the step. A 300lbs robot composed of wood, probably does not have this feature. Plus, wood is much harder than flesh (duh). Get a 300lbs pirate with wooden pegs for legs and watch him fuck up your stairs in a few weeks.

Cool!

[jrobinson5]

Where can I sign up to order one of these 300 pound pirates with peg legs?

Re:

[TommydCat]

Ye kin orrrrder a schwabby from "Pirates RRRRRRRRRRR Us", of courrrrse!

Re:I hate to (have to) ask...

[hotdiggitydawg]

You missed the major factor - contact surface area. If you've got a polished wood floor, a 120lb woman can very easily damage it in high heels if the surface area of the heel is small. I imagine a 300lb geek dressed as a pirate in high heels would go right through to his parent's basement.

Re:I hate to (have to) ask...

[Chris Burke]

I don't know, but I'm thinking he'd view his project as much more of a success if he simply re-defined it. Machine for carrying groceries up stairs? No! Automatic Staircase Destroyer? Hell yes!

Re:I hate to (have to) ask...

[dapsychous]

You work for Microsoft, don't you?

Re:

[fotbr]

Thanks, but we SI impared people don't normally use decimals when measuring feet. We inherited this goofy unit called "inches".

And 300 pounds is a bit over 20 stones, if that helps your imagination any.

While in my engineering college ...

[Utopia]

... I build a radar.
Now I don't build cool stuff I just write code.

Ronja project

[Anonymous Coward]

I have built Ronja Optical Datalink (FSO) according the instructions on the homepage (ronja.twibright.com [twibright.com]). It's amazing to build a wireless network device on your own.

Mine

[iamdrscience]

One time I made a "Jump to Conclusions" mat. You see, it was this mat that you would put on the floor... and had different conclusions written on it that you could jump to.

Re:Mine

[zerojoker]

That's the worst idea I've ever heared of. Yes, this idea is horrible!

Comment removed

[account_deleted]

Comment removed based on user account deletion

Re:

[Chairboy]

I'm also building an airplane, a Cozy Mk IV (a 4 seater version of Burt Rutan's LongEZ).

Airplanes are very fulfilling projects, well suited for this crowd.

Re:

[worst_name_ever]

RV-7 here. And since I'm posting on /. you know my panel will be geek-pimped out!

Re:

[MadEE]

I have been interested in that craft. How much has it cost you and how difficult has the construction been on that model? Any other weirdness?

Re:

[JourneyExpertApe]

2007 should be the year...

I'd hold off on having your tombstone inscribed just yet. You might not finish the plane until 2008.

Biodiesel Reactor

[Anonymous Coward]

My first semester at UW Madison my Introduction to Engineering class buit a BioDiesel Reactor. It was 18 freshman students who knew nothing about biodiesel, and by the end of the semester we designed and constructed the reactor. I was involved on the team that designed and executed a safety system that monitored the temperatures inside the reactor tank, if the temperatures exceeded 60 degrees celsius a relay shut off the heating element in the reactor. This was one section of a larger lecture, and all other projects pailed in comparison. We also had a $500 budget which we exceeded by $4500, the project was paid for by a department at a technical school in Madison.

Re:Biodiesel Reactor

[Anonymous Coward]

We also had a $500 budget which we exceeded by $4500, the project was paid for by a department...

have you considered a rewarding and successful career with the United States Government?

Re:

[Alchemar]

but the project was completed on time, that would never be acceptable in the fast passed world of government funding. They would be able to see if it works before paying the bill.

Re:

[mwpierce]

I built one of those too out in my shop. I was one 40 year old geek who new nothing about biodiesel but wanted to "stick it to the man". It took me about 2 weeks to build a complete system using information off the internet. I didn't tell my wife of the hazards and risks so I didn't need a safety system :) This think worked great and produced several tanks of biodiesel for my 1 ton truck. One day the cows broke into my shop and one of them thinks of rubber hose as licorice so she ate all the tubing work goi

amstrad Teletype

[CdBee]

Back in the 80s I had 2 Amstrad CPC464 personal computers (Z-80 CPU, 64k, tape deck built-in). I built an electronic circuit to link the joystick port from one to the sound-out port of the other (sound triggered a switch-effect using transistors)

I wrote Morse-code modulator/demodulator software and set them up as a simple text-based comms system down the garden...

A custom kernel

[bogaboga]

The coolest thing I ever did was build my own custom Linux Kernel. It was way back in the year 1999 when the process was not that straight forward. My distro was called `Bogaboga Linux' and is still available on a 486 system.

Couple of things

[tompaulco]

When I was about 11 or 12, I helped my dad build a Z80 based computer. As far as what I have done one my own (although the article had three people), all of my early exploits were software based. When I was around 13 I wrote the entire game of Monolopoly on a TRS-80. A few years later, since I couldn't afford Tetris, but I had seen how it worked, I wrote Tetris on my very early PC.
Nowadays, I build more hardware stuff, but it is not as cool because I am an adult and should know how to build it. For example, I built a 180 gallon saltwater reef tank with an oak cabinet, aut water replenisher, Carbon doser, protein filter and all kinds of other accessories, and plumbed the sump down to my basement.
A few years back, I built a 20X40 swimming pool with diving board and slide, and built a 70X40 concrete deck (yes, I mixed and poured it myself) with cedar railing to surround it.

an IM client on a TRS-80

[AWhistler]

With a friend I built and wrote an IM client that worked between two TRS-80 model I computers. We "networked" them together by connecting the tape drives between each other (needed an amplifier), and cross connected the "send" and "receive". Then we wrote software that accepted input, sent it across the tape drive, then listened for a message from the tape drive.

It worked well, but of course was very slow.

Then there's the joystick-controlled typewriter...but that wasn't as cool.

Re:

[AWhistler]

Oh yeah. I saw a friend write a space invaders game in the built-in BASIC, so I proceeded to learn how and wrote one myself. That was a neat trick since the TRS-80 was too slow to do real-time games without assembly code, but it worked well. That was pretty cool at the time.

* ft tall water balloon slingshot

[Registered Coward v2]

We were the terror of Fraternity Row. It used steal pipe and multiple pieces of chem hose - after a little practice we could lob a water balloon through an open window hundreds of feet away.

Burningman

[Anonymous Coward]

You want to see some neat engineering? Most is not practical at all which means it's all that much more awsome. Go to Burningman [burningman.com]

A partial computer!

[IversenX]

As a freshman in the danish "gymnasium" (which is senior year of high school + 2 years of college), we had
an project in physics class where we could write about anything we wanted to. As a group of three students
we chose to write about digital logic. In the beginning, we only planned to write about digital logic theory,
circuit design theory, and so on, but we soon realized we wanted to build an actual circuit design.

After spending days or even weeks designing the thing, we finally had our ÜberMachine - we called it the
DALO (Digital Arithmetic and Logic Unit). It was essentially an ALU with support for addition, subtraction,
logic "or", logic "and", and logic "not".

Now, in this day and age of computers, it would take most programmers just a few minutes to make such a program
in most programming languages. But this was done entirely in hardware, with no fancy integrated circuits! We
used about 15 simple chips (classic phillips 74xx-series), which only contains or, and, not and the occasional
full-adder.

For the input, we used manual flip-switches, connected directly to the input legs on the microchips.

For output we used a series of LEDs to output each of the 4 digits in the A-input, B-input and the result. At
the same time, we used a classic 7-segment display for each, driven by a 7-segment-decoder chip.

In the end, the things actually worked, which was quite amazing to see. We hadn't received any formal training
in digital logic, electronics, or circuit design - and yet it worked. The entire machine was soldered with more
wires than I ever wish to see again, and it took a lot of blood, sweat and... time - but we did it!

Some years later, I was employed as a teaching assistant at the university. One of my classes were in machine
architecture, a course which most students couldn't see as relating to reality very much, because they didn't
believe anybody except large companies could build computers or circuits. On the day of my last class, just a
few days prior to the exam, I brought our high school project with me, and showed them how it was built.
Several of them were amazed by it, and it really seemed to make a difference. Computers were no longer magical
devices crafted by dwarven builders, they were simply complex machines, free for anybody to build.

That's the greatest thing I have ever built. Now, if we were talking about programming, that would be
another matter... :-)

A robot that can traverse staircases

[drgroove]

I built a robot in jr high that could walk up and down stairs. The robot had two legs, w/ four feet, two on each side. Each leg was bound to the robot's body using a turning motor in the center of the leg (which was really just a tubular pipe about 1 ft in length). Each leg had one foot on the end, which had a flat, circular surface that was adjoined on a small 1" pipe, attached to the end of the leg. The feet could spin freely at the endpoint of the leg. So, when the legs spun, the feet rotated around. Gravity moved the feet flatly towards the floor. Walking up stairs, the robot would have two feet on the current stair, with the next two rotating upwards or downwards towards the next stair. I built in a little button on both sides of the robot's body that would alternate the direction of the leg motors, so when the robot got to the top of the stairs, it would bump the wall, change direction and walk back down. About every 3 weeks I'd change the batteries and put it back in action. Pity my poor parents, having to walk over my robot anytime they wanted to go up or down the stairs for about 3 months!

Re:

[myrdos2]

I built a tele-operated robot a few years ago. I got the biggest RC vehicle they had at Radio Shack, built a water-proof plexiglass box to hold the motherboard, and hooked it up to a wireless adapter. I used a 533 mhz fanless VIA mini-ITX board, and it had Debian Linux through a flash drive. The vehicle was controlled through the parallel port.

Here are some pics: http://www.junction.bafsoft.com/telebot2/ [bafsoft.com]

A 'clue meter' for the office

[nurb432]

Too bad i cant get it to move off zero, must be a flaw in it somewhere....

Not Cool

[camperdave]

I built my own computer, but it's not very cool. In fact, it can get quite warm at times.

Nixie tube display for a computer

[Alioth]

A few months ago, I started learning electronics. My first project is (electronically) complete - it just needs some finishing off to the housing.
It's a Nixie tube display, with 7 nixie tubes. I built an RS-232 reciever/sender out of 4000-series logic ICs (not a CPU or microcontroller in sight) - mostly counters and registers, and a few AND gates and inverters.

Pictures of the project's progress are at http://www.alioth.net/pics/nixies/nixies.html [alioth.net] (two pages of photos - the working project is on page 2). I've also kept a journal of building and learning in my Slashdot journal.

The hardest part of it was probably getting the 170 volt switch mode power supply to work correctly (mainly getting it to regulate) and not put so much noise back into the 5 volt supply to cause latches and registers to lose their values. Some help from the NEONIXIE-L group on Yahoo was invaluable here, and I now have a decent 170 volt supply.

I'm now learning how to make things with microprocessors, and once I've done some breadboard experimentation, my next project is to build a logging weather station for the glider club, using a Z80 processor, a flash EPROM, some RAM and probably compact flash for mass storage (not that it'll use a lot of it!), and a small graphics LCD module for display. Currently, I'm at the stage where I've breadboarded a very basic Z80 system that can output values on a crude output device. But it works!

Re:

[rbanzai]

Great pictures! I love nixie tubes though I've never done electronics. I just like the look of them. It's nice to see the "ugly" electronic truth behind all these lovely pixels.

Lego

[Ant P.]

The coolest thing I've probably built is still the car thing I stuck together years ago out of technic parts, with a moving engine block and weird cantilever suspension. I lost it somewhere :(

An AM transmitter

[Announcer]

It's designed for use on Amateur Radio frequencies, specifically between 3700-4000 Khz and uses basically the same technology as broadcast transmitters from the early days up to the 1960's.

Here's a Coral link to it:

http://www.mymorninglight.org.nyud.net:8080/ham/61 46.htm [nyud.net]

The best part about it, is that I built it entirely from stuff that was headed to the scrap heap!

There are other interesting or unusual things I've built, which can be seen by following the links. In one especially unusual project, I used the analog circuits from a fried SoundBlaster card, and a CD drive as a modulator for a tube-based, low-power AM transmitter. Combining 2000's technology with 1950's. It worked, too!

Igloo

[owlnation]

I built an Igloo once, that was really cool.

Sorry...(ducks)...

Re:

[Bastard of Subhumani]

I really did build an igloo! Three of us slept in it overnight. It was surprisingly comfortable.

Built, but never tested

[svunt]

I once built a super-sweet ride, but I never got to really enjoy it, as it's prohibitively difficult to generate 1.8 jiggawatts of power.

My best - the Abtaser (and my other IP flops, too)

[transporter_ii]

Been working on a list of my biggest inventions and intellectual property items that flopped in a big, big way. My coolest inventions and IP flops are:

• My book, "Men Are From Mars, and Women Love Martian Penis," failed to crack the NY Times Best Seller list for five consecutive years after publication.

• NBC cancelled my sitcom, "Nudist, With Children," before a single episode was aired.

• My idea for non-decomposing toilet paper never made it to market.

• While at first very successful, my tubs of chocolate-chip cookie-dough flavored roach poison, designed to fool even the most intelligent roaches, were pulled from shelves nationwide. While a federal judge initially upheld an injunction on the recall, the injunction was later overturned by a law created in a special session of Congress (the law was named Kimberly's law, in honor of the memory of the two-year-old baby Kimberly).

But my all time coolest thing I have built, and my biggest tech flop, is one I called an abtaser:

Abtaser [thearmedcitizen.com]

Because of their small size, AbTasers can fit easily in your purse, bag, backpack, coat etc. Other Ab products, like Ab belts, are bulky and only work your Abs. The AbTaser's design lets you not only work other parts of the body, but you can work other people's Abs from up to 15 feet away!

Conveniently carry it with you whenever traveling around town, shopping leaving bars or night clubs, using pay phones, parking lots, garages, alleys, subways, bus stations, home alone, walking, jogging, running errands, deliveries, and for house wives, students, daughters, night workers, drivers, law enforcers, sales people, travelers, security guards, etc., and for anyone needing or wanting extra exercise.

Other low-power Ab products have to be used for an extended period of time. The high-powered AbTaser works every muscle in your body in a split second. And again, not only is it capable of working your abs, but you can also work the muscles of others up to 15 feet away. Imagine your bosses surprise when you decide he needs a little exercise! AbTasers are great for relieving stress, too. Feeling down, feeling blue? AbTasers will give you a new outlook on life!

*Check federal, state and local laws before ordering your AbTaser! Do NOT carry your AbTaser concealed. Do not attempt to use the AbTaser while operating a motor vehicle. Do not use the AbTaser on someone else operating a motor vehicle. Do not attempt to board aircraft while in the possession of an AbTaser.

Automated Monorail

[rongage]

I think the coolest thing I ever built (or designed and programmed) was a self-contained turntable system for an automated monorail part transport system. The thing had multiple stop points that could be programmed, automatic homing, and built-in accel/decel ramping. Used a mini handheld pendant to program the stop points - you could literally walk under the thing and see the alignment as you made your adjustments.

To the best of my knowledge, it is still in production at Caterpillar today. It was designed and built in 1998.

The second best coolest thing I ever built was some software for interfacing a Linux based PC to an Allen Bradley ControlLogix PLC. The real cool bit is knowing that this software is being used in multiple production facilities around the world from making baby formula in Canada to being used in a mix simulator for the AirBorne Laser program.

Cheap supercar

[Lumpy]

Put a corvette LS5 engine in a pontiac fiero. I now have 1Hp at the wheels for every 6 pounds of car. I can put crotch rocket motorcycles to shame, and eat any "fast" car I get challenged by.
Cost me a total of $15,000.00US and a year tinkering. the car costs $350 a year to insure and takes everyone by suprise that tries to race that slow old 80's wannabe sportscar.

Biggest drawback? touchy to drive. if you sneeze while accelerating slowly you suddenly burn the tires hard, have the nose lifting off the ground and are starting to go sideways. It's dangerous for anyone that doesn't know how to drive insane levels of Hp to weight ratios.

Re:

[tompaulco]

I have a cheap supercar, too. An '88 Lotus Esprit (about $17k these days). Earlier this year, the transmission input shaft bearing destroyed itself, so I completely disassembled the engine, got a larger bearing, had a machine turn the crankshaft to accept the larger bearing. Got the flywheel polished, got all new gaskets, rings, bearings, new clutch plate, input shaft, and all kinds of other stuff. I cleaned everything up in a parts washer, and got it all back togethr, and it actually ran. I had some help f

Re:Cheap supercar

[Lumpy]

LS5 is a chevy big block that was in top production in the 70's the fact it was a muscle car engine gives me HUGE aftermarket performance parts that makes it really easy to generate 500+hp. Instead of using girly fuel injection I have a nice set of carbs on top that really unleash the power.

Cool part, engine is near indestructable because it was made for power and over engineered. The go-fast parts are way cheaper and with a simple adapter plate It was easy to adapt it to a strong 6 speed FWD tranny.

Problem is, IT eats axles. IF I sit still and floor it in first I will get about 200 feet before I rip a standard axles apart. I have a set of suctom made racing axles that are supposed to be 5X stronger and hope to get them installed this winter.

Kegerator

[Kairos21]

I built a 2 tap Kegerator with a tile counter and a computer to weigh the kegs and tell how much beer is left in each keg. Check it out here http://photos.yahoo.com/melendez_21 [yahoo.com] I also installed a glass door to keep liquor cold with a black light.

Re:

[ArsonSmith]

As a fellow kegerator builder I must give props on a very well done one. I love the tile top.

Mine was built out of an old fridge that was just large enough to hold a keg. I then just drilled and put the tap in the door. I shaved off the handles and cleaned up/painted the outside to make it look nice, then painted the inside with a gold spray paint. Figured the keg should sit in a bed of gold. Only other thing I wanted to do was make it so when you opened the door, angelic music would play. You know th

several machines

[ArsonSmith]

About 2 years ago I decided to get into hobbie prop building. One of the first things I built was a vacuum-forming table out of some MDF an empty beer keg a bit of metal from Home depot and a home built heating element.
http://24.251.127.62:8088/gallery/vacformtable [24.251.127.62]

I have used this thing to make several diffirent things from speaker boxes to Stormtrooper armor. It has been a blast. The latest project I have made has been a rotocast machine.
http://s14.photobucket.com/albums/a331/arsonsmith/ Rotocast%20Machine/ [photobucket.com]

I started by building the lego mock up at the bottom of that link then started aquaring the other parts. It has been used to make several diffirent things from replica guns to costume masks and helmets.

Re:

[ArsonSmith]

Wow I make a lot I forgot about some of these other things.

This came from an article in MAKE Magazine
http://24.251.127.62:8088/gallery/PotatoLaunchers [24.251.127.62]

This I got the idea from slashdot back 5 or 6 years ago when the Mame cabinets were all the nerdy rage:
http://24.251.127.62:8088/gallery/MAME_Arcade [24.251.127.62]
The one with the Mame across the top was built from scratch.

This one is still in my garage and is on the back burner right now but needs to be completed:
http://24.251.127.62:8088/gallery/JeepUpgrade [24.251.127.62]

Please go easy o

Linux from scratch

[owlman17]

Old-timers used to do this routinely, but for relative noobs like me, linuxfromscratch.org [linuxfromscratch.org] nothing beats the joy of rolling your own distro, boot-strapping the compiler, etc. I suppose, those old-timers still find joy in doing this.

A Human Powered Submarine.

[slashkitty]

Here is the international contest we entered into: http://www.isrsubrace.org/ [isrsubrace.org]

Well, I didn't actually see the end of the project, but we got a lot of it done. It was an awesome design, carbon fiber shell, aluminum frame and cool prop.

The Ghetto Router!

[markhagan]

Duct tape, paper clips, electric tape, a broken Linksys switch, and a 486, FTW!

http://www.extremeoverclocking.com/articles/howto/ Ghetto_Router_1.html [extremeoverclocking.com]

A couple of things...

[Chairboy]

I've built a few things I really liked:
1. Building an airplane (200+mph 4 seater version of a Burt Rutan design)
2. Flamethrowers (the response time of the Culver City police department to 40+ foot flame mushroom clouds is 5 minutes)
3. TankCams - I've explored the crawlspace under my house from the comfort of my living room via teleoperation.
4. A couple of neat costumes, this year I was written up on slashdot about my Aliens walking forklift costume.
5. An inertially coupled autopilot for R/C planes I built years ago as a cheap UAV so I could send a plane someplace, take pictures, then have it fly itself back, all without crashing.

There are lots of cool things to do out there, I'll be dead when I stop working on them. Instead of being a "remember that time back when I was held the football record at Polk High" thread, I hope this thread focusses not just on past accomplishments, but also mentions things people are still actively doing, otherwise it'll be terribly depressing.

Tunneling Scanning Electron Microscope

[Hiigara]

While I was a Junior/Senior at Everett High School, (Lansing, Michigan), I built a tunneling scanning electron microscope. We originally followed/used a kit from the University of Muenster in Germany that I had learned about from Slashdot. Unfortunately, the documentation sucked, the circuit board was etched incorrectly and there was a design error. Furthermore, the control software was written is visual basic and was nothing more then a toy.

With the help of a electrical engineering group at Michigan State University we overcame the problems and I decided to modify the original design to use GXSM, a powerful open source electron microscope software package that is Linux only. This required adding a sranger digital signal processing board and stepping up the input/output voltages for the piezo crystals. Amazingly, almost all the work was done by myself or fellow students, MSU only guided us in understanding the circuit diagrams, making small adjustments, fixing the errors in the plans and designing/building the stepping circuits for my modifications.

I have some really great memories, spending all day in the basement lab I had set up, eating pizza while skipping all my classes with permission from the principal, "accidentally" burning my long time enemy with the soldering iron, ripping a chunk of my finger off jumping a network wiring cage to connect the main computer to the internet.

Working with the electronics and science was very interesting, but the most valuable experience came from lobbying for the funding from local government, assembling a team of fellow students to work on the project and starting a Nanotechnology elective class to actually use the damn thing. Eventually, former State Senator Virg Bernero (now Mayor of Lansing, Michigan) convinced BioPort (the company that makes the Anthrax vaccine) to provide the majority of the funds.

The project eventually inspired local university and government leaders (I wouldn't stop bugging them ;)) to support accelerated Nanotechnology development and commercialization while also encouraging applied and basic research. Michigan State University and the surrounding universities are home to world class researchers and students working on Nanotechnology and Nano-Biotechnology. It has been decided that it is time the state began to leverage that asset to create a bright 21st century future for our citizens.

I'm 19 years old, and thanks to the Slashdot article "build your own electron microscope" I've actually become something I'm proud of. I've built a tunneling scanning electron microscope, lobbied for funding and government support, founded a Nanotechnology class at Everett High School with help from a amazing science teacher who now is inspiring the class to even greater things while developing a soon to be accredited curriculum, hired as a contract consultant by a company in silicon valley, been sent overseas, all expenses paid to a nanotube conference in Japan by the same company and I now work at M.S.U. as the only employee in a new Nanotechnology supporting office at the college of Engineering. (There is also some other stuff I'm not allowed to speak of.)

I've met very important people from NASA's JPL, IBM, Oxford, Harvard and founders/pioneers of Nanotechnology.

In my free time, I lobby for the creation of a Michigan Institute of Nanotechnology, which will become the center of Nanotechnology in the state, facilitating the cooperation of private industry, research, academia and government to create jobs, businesses, breakthroughs and secure a portion of the world economy for ourselves. It already has a extremely wide and powerful base of support.

Not bad for someone who graduated with a 2.5 GPA.

Links

[Bromskloss]

the Slashdot article "build your own electron microscope"

Build Your Own Scanning Tunneling Microscope [slashdot.org]

GXSM, a powerful open source electron microscope software package

Gnome X Scanning Microscopy [sourceforge.net]

Re:

[Dr. Smeegee]

If you damned kids would get off your asses and start doing something besides playing video games then we wouldn't be loosing our jobs to the danged Chinese!

Pneumatic scat launcher

[TofuDog]

A couple of years ago I built an air cannon [corin.com] for the purpose of launching mountain lion scat at prey species, as part of my study of prey responses to cues of predation risk. My first test-firing of my dog's turd (using a foam coffee cup sabot) launched it's payload >200 m towards a house on the next street (I hid rather than verify the point of dookie impact). Imagine, if you will, the joy of recreating the primal thrill of monkeys hurling their excrement through the bars -all under the guise of science, of course. Alas, the seals in the sprinkler valves blew out after a dozen firings and I reverted to the low-tech slingshit to complete my experiment. Now if I would just finish writing the Ph.D. instead of posting to slashdot...

An NPR demo reel.

[Grendel Drago]

It's not exactly *built*, but I'm still proud of it.

Back in 2001/2002 or thereabouts, there was a film festival in the art department. I spent several weeks making a nonphotorealistic (cartoon-style) demo reel. I wrote some PHP scripts to generate the RIB files, wrote a pair of shaders (for cel-color and edge generation), and generated a couple of megabytes of scene description to feed into BMRT. (I even wrote a shader which made that red-yellow-and-blue Pixar ball, the one in the lower-right here [wikipedia.org], procedur

I built a model Maglev.

[NoNsense]

Throughout high school, I was forced to do Science Fair projects. I picked MagLev's. I did experiments, wound my own coils, did a bunch of different tests and moved my project along in different phases during freshman to junior years. Senior year I was able to get a mini grant and order from Scientific American for some rare earth magnets. It was not as automated as I liked, but I had built stepping logic and used my own coils to at least show things are possible. If you've been to Epcot there is a demo which was very close to what I built in my senior year. I can't say they were equivalent. I was very depressed once I saw it, but then again I was only 15, and it was Disney, they had all the toys.

Fast forward to college. Senior project and after taking all the courses in logic, programming, processors, etc I then found out what I could use to make my toy work. So, I spoke to my advisor, he loved the idea. I spent that summer winding coils with 26 gauge wire. I made a length of track two feet long and I it used 48 coils. I used sewing machine bobbins as the sizing. I cut a 3/4" pvc pipe so that I could slide in each coil and get to the leads. This gave me four sections of track, each with 12 coils. The coils were wired in series so that we had a pattern ABCABCABCABC. The logic I built would pulse the A group at 12v, the B group at 9v and the C group at 6v. This created a "wave" that would "push" the train in the desired direction. To go the other direction, all you had to do was flip a DPDT relay and switch A with C.

The brains were provided by a Parallax Stamp 2. This thing was great. I could have multiple inputs and outputs to make everything work. I used som buffers to make sure I didnt kill the chip with draw and I used logic to drive transistors that tripped 12v relays for the juice. When working, the train could go one direction or the other, depending on how the coils were energized. Since the track was only 24" long, I used optical led sets to detect where the car was. These inputs were fed into the stamp. Based on direction and track section the car was on, the group of 12 coils were the car left was turned off, and the section the train was about to enter was turned on. Of course, there were always two sections on so if the train was in section 2 going to section 3, then the stamp knew to switch off 1 and turn on 3, leaving 2 running. The car was pulsed slow, so it had time. Was not as smooth as I liked.

Had to use a huge power supply, 12v 30a, tho I think it only used between 8 and 10. I still have it on a shelf behind me. Maybe one day I'll dust it off and see how I can improve on it. It blew away everyone else's project. Once I started the car rolling, it would happily go back and forth all day long. It was stable (temperature wise) and if you ignored the clacking relays, it was fun to watch.

It is not the coolest thing I've ever worked on or designed, but in terms of what I put into it and the fact it was my brainchild, I'm totally thrilled with it to this day.

A Yurt

[Weaselmancer]

Yup. A yurt.

It was actually a pretty geeky project, too. I designed most of it in Maple.

An ethanol still

[bergeron76]

I'm building my own Ethanol Still [clubethanol.com] (mirrored from tripod [tripod.com]). A little bit of corn mash (or beer) and out comes E-100 Ethanol Fuel.

Previous to that, I built one of the first carputers (the DashPC [dashpc.com]) back in 1999 (it was slashdotted 3 times).

My next project is to make our new project car run on my own homemade E100. It's a 1995 Ford Festiva that gets about 50 MPG right now.

My coolest...

[multimediavt]

Well, I helped design and build what was the third fastest (public) computer in the world three years ago, System X [vt.edu]. That was pretty cool. I'm still not done with doing stuff like that yet. ;-)

Car stuff

[gorehog]

A clutch alignment tool for a nissan that had no pilot bearing.

Though a lot of people think it's that incense burner I made from a pringles can.

A clock radio!

[rspress]

Back in the early 70's myself and my friend had a contest to see who could come up with a clock radio. These were real Rube Goldberg devices and the more extra features they did the more points we got. Both of our designs pretty much took up the whole space underneath out respective beds. Since we lived in the same apartment complex it was easy to check out each others designs. He would come over to my parents house and check mine out and I would go to his parents house and check his out. Stealing ideas was just fine. We robbed our electronic parts boxes. Mine used a wind-up alarm clock that pulled a string to engage a old radio tuner to make connect with a battery, this in turn engaged other devices such as a motor with a weight on one side connected to the bed for a magic fingers effect. A large 15 inch speaker give you a nice thump to the bed frame in time with the music. Each bell on the alarm clock was wired to a buzzer wired to one bell and a light wired to the other bell. The striker was connect to a battery and when the alarm went off it would alternate between the light and the buzzer.

Of course they were accidents waiting to happen and I am surprised we never burnt our respective apartments down. But hey for 12 year olds back in 1973 it was great fun!

Material things?

[Bluesman]

A buddy of mine and I in high school entered one of those King of the Hill competitions where you had a list of household items you could use to build a machine, and a set of objectives to accomplish.

There was a tie-breaking rule -- if no objectives were completed, whoever got furthest up the hill won.

So, figuring that nobody's machine would work perfectly, we built a car that ignored every objective but was lightening quick and used all of the allowed mousetraps to either propel itself or flip the other car over.

Our plan worked flawlessly, and in the last round we knocked the over car almost completely off the hill.

I see it as the ultimate engineering victory -- finding the easiest/cheapest way to accomplish a task in a competitive environment. Although I do think the organizers were a bit disappointed that we won.

Matrix BulletTime on the cheap

[higgins]

I didn't build it all myself, I was just on the team, but we made a rig that simulated the Matrix BulletTime effect using 32 $20 Mattel Barbie digital cameras. The cameras were mounted on foam core and corrugated plastic, arranged in a big circle, and we used truck mirrors to get a wide angle effect. All the cameras were wired to a central triggering circuit, and we used a garage door opener as a remote control. You would go into the center of the circle with your friends and some props, do something crazy, and hit the remote. The cameras would fire --- then all the pictures would be sent to a printer which would print out a flip-book on cardstock so that you could see a low-tech animation of yourself spinning around doing whatever.

Here's some propaganda about the project. [maya.com]

In the 5th grade

[Zex_Suik]

I made two working telephones completely from scratch, the coolest part were the microphones:

they were essentially the bottoms of paper dixie cups, I crammed powdered coal into them with electrodes at each end and taped them up. Ran a current into them. As you spoke, the sound waves compressed the carbon allowing the current to run faster or slower through the carbon.

Worked great. Wasn't too sensitive so it didn't pick up whispers and stuff.

Sferics Recorder

[Aging_Newbie]

In high school my junior year ('65) I built a system that displayed electromagnetic radiation from lightning strokes on a CRT. I had little money so built it from old TV and surplus parts. Three foot loop antennas oriented N-S and E-W picked up the signals and displayed them on a scope tube. The whole thing was vacuum tubes, I think around 8 or so. That was pretty cool but not all I wanted. The next year, I contacted IBM, who helped me with schematics of flip flops and other logic implemented with transistors (wow!) and I made a recorder that would write the signals on paper charts so I could correlate them with the next day's newspaper reports of distant storms. The recorders were constructed of old speakers with the cones removed but the voice coils still in place, recording pens on long arms that magnified the motion of the voice coil, and a coffee can driven by a clock radio movement that moved a sheet of paper under the pens every 12 hours. I ran it a whole year and tracked storms as far away as Lousiana from my house in Minnesota by the lightning they produced. It was pretty neat. I also tracked some tornadoes that I recognized by the almost continuous lightning they produced. It was lots of fun and I won some awards at the science fair.

It also got me a college scholarship to get into a physics program, which I wouldn't have gotten any other way. So, now you know how I came to be spending my Saturday afternoon typing into Slashdot.

FPGA integer factorization implementation

[RKBA]

Since my retirement I've taught myself the Verilog programming language (yes, Verilog is a programming language regardless of what hardware designers will tell you) and designed FPGA hardware implementations of the following:

1. Lenstra's Elliptic Curve Method (ECM) of integer factorization.
2. Fermat's method of integer factorization.

It turns out that the ECM design was far too large to fit into any existing FPGA, so I now have two different FPGA development boards running Fermat's factorization method on RSA-704 and RSA-768 respectively. Yes, I know the Sun will engulf the earth before either FPGA development board comes up with an answer, but they both display a lot of pretty colored blinking lights while doing the calculations so they make a great conversation piece - Har. :-) Besides, I did this primarily as a learning exercise for myself in lieu of spending my time watching brain-dead TV programs, etc.

Fusion reactor

[hairykrishna]

I built a Farnsworth fusor. CLear above background neutron signature and everything.

I win

[jbrader]

Back in high school I made a really huge bong out of 1 liter soda bottles and aquarium tubing.

Smoke screen on my car.

[jaided]

In the summer of 1988 my two biggest hobbies were Radio-control airplanes and modifying my 1969 Firebird.

I was interested in putting a skywriting system on one of my RC airplanes. The kits were expensive so I looked into the methods used by the old-timers on real airplanes. A common DIY method back in the day was to pump a 50/50 mixture of diesel and transmission fluid right into the engines exhaust headers. My first thought was "Forget the airplane, this would work on my car!" I ran down to the hardware store and bought some brake lines(metal tubes threaded on the end), fuel hose, 1-gal Gas can, etc. Then I ran to the wrecking yard and pulled the first electric fuel pump I found. The whole project was easily under $20 at the time.

I drilled holes in all 8 exhaust headers of my Firebird as close as I could to the manifold and tapped them so I could thread in the brake-lines. I ran them all back to the electric fuel pump, which then lead to the gas can. I filled the gas can up faithfully following the 50:50 Diesel/Tranny-fluid mix and set out to test it on some abandoned logging roads.

On the drive there I was thinking about what I might need change to improve it. Would the fuel pump be enough? Will I need to slightly constrict the shorter hoses so the mixture reaches all the headers simultaneously? Will I need to adjust the mixture?
The first test worked so ridiculously well that I never bothered optimizing anything. Thick, white smoke filled up both lanes of the access-road nearly to the tops of the trees. I had to wait several minutes for the smoke to clear before I could drive back through it..

I used it responsibly for the most part (if that's even possible) but you just can't have something like that when you're in High school. I remember one friend borrowing my car at lunch and completely shutting down traffic for about 10 min. on the highway in front of our High-school. Another time I was at the movie theater parking lot and a crowd of "popular kids" from school begged to see it. I revved the engine and fired off a "small puff" while parked. Two police cars showed up when the saw the 300' "mushroom cloud" over the theater and I had to convince them that the rings were going bad but the car only smoked "sometimes." Yet another time a "friend" hit the switch when I wasn't looking at a stop light in downtown Portland. I looked back to see what all the honking is about and I see no cars, no buildings, just a while cloud. The rest of that story is a calamity that I don't care to elaborate on. I will say that nobody was hurt, though.

I dismantled it after that and never made another. The fun/stress ratio wasn't even close to being worth it.

Rockets

[sakusha]

Like many kids in the 1960s, the coolest thing we could get our hands on was Estes model rocket engines. I particularly loved to make "boost gliders" which were devilishly difficult to build right. They were complex because they had a large rotatable wing. During the boost phase the wing was retracted parallel to the main tube, but after the rocket burned out, the propellant module ejected and the wing would rotate out to a configuration like an aircraft. The idea was that the rocket would shoot upright to maximum altitude, then the wing would deploy and it would fly in a flat spiral, then land close to the launch site. If you did it wrong, it would go up and then fly off in a straight line off to the horizon, never to be seen again.
The best rocket I ever made was a scale model of the BOMARC, one of the first cruise missiles in the US arsenal. I spent weeks making sure every detail was perfect, it looked beautiful, even the paint job was polished to mirror-like perfection (very difficult for a 12 year old kid like me to achieve). The aerodynamics looked good, although scale model kits were notorious for poor flight qualities since sacrifices were made for the sake of accurate design. But I managed to static test the rocket until it worked right, this was done by attaching a long piece of string to the rocket's center of gravity, then whirling it around at the end of 20 feet of string, watching its flight dynamics until you puked from dizziness. A little trim balancing here, a little added weight there, and everything was perfect.
In fact, so perfect I didn't want to launch it. I hung the rocket from my bedroom ceiling, where I fondly gazed at it every night as I lay in bed. Eventually I decided I had to see it fly. But to minimize the risk, the first flight would be a small rocket engine, I didn't want to shoot it up 2000 feet and maybe never see it again, a small 200ft flight would be sufficient. Whenever I set up my launch pad, all the neighborhood kids would suddenly show up to watch the launch. 3..2..1.. blastoff! It popped up, the engine ejected, and the BOMARC flew in a perfect spiral about one block in diameter. All the kids started chasing after it, back and forth, as it lazily spiraled around up out of their reach, I laughed and laughed. I stood right by the launch pad as the rocket started coming down, it looked like it would land almost at my feet.. and it DID! And then one of the kids chasing it STOMPED right on top of it, smashing my beautiful rocket to bits! Dammit!
I think I gave up building rockets after that, my heart wasn't in it anymore.

Oh yeah.. I do recall building one cool rocket, once I was an adult. I found out that ultra high performance engines had come on the market, I think this was the late 1970s. No more wimpy Estes D engines, these were E, F and G engines. I heard there was a 2 stage rocket kit that would break the sound barrier, so I ordered one. IIRC, it was a G engine with a D on top of it. No sense in buying more than one set of engines, this kit would go up thousands of feet and come down miles away, I'd never see it again. The fins were made of composite balsa plywood, regular plywood would just break apart when it hit the sound barrier. The fins had to be epoxied carefully to the body tube with perfect fillets, construction details were crucial, the kit instructions said that the slightest flaw would cause the rocket to break up and smash INTO the sound barrier, rather than through it. It also recommended not painting the rocket as the least imbalance (i.e. more paint on one side than the other) would have an adverse effect.
So I built the rocket, and my friends got together so we could launch it. We had to find a big field because you were supposed to stand at a specific distance away (~250 ft IIRC) so you'd be in the right spot to hear the faint sonic boom. We brought a long tape measure to mark off the distance precisely. I only had 20 feet of wire to run to the electronic igniter, so we drew straws on who would launch, the poor sap who pressed the button woul

MFG machine

[Old.UNIX.Nut]

In 1980 I built a machine to manufacture Cement Pipes using the "centrifugal molding" ** process. The pipes are 20' in length and 1.5' to 6' in diameter - single or double wall thickness. If you live in S-California or S-Nevada then some of those pipes reside under your city streets.

** cement is fed into a spinning mold by a complex feeder (my part of the project) that rolls on small train rails, then put in to a steam room. 4 hours later you have a pipe outside the mold "curing" in the sun.

A Pan flute.

[jotaeleemeese]

If you think that is easy, check all the arithemetic required to make one that is actually in tune.

Re:

[l810c]

My senior year at high school, we were supposed to build a float for the high school parade. Instead, we built a 10 foot high paper mache penis and placed it on top of the school right over the principal's office.

Re:

[snooo53]

How did you transmute the wood into rock? This sounds suspiciously like a totem pole...