These ice dentures should be a hit in the punch bowl at granny's party! If you want to pick up a set, try Amazon.

There are a few clever pranks here. I particularly like the Mentos stealth geyser. From the Mischief Makers' Manual.

The tradition of improvising a chess set from whatever's on hand is probably as venerable as chess itself. Chess culture is chock-full of sets put together from odds and ends of every description, but here I'm only focusing on sets built from mechanical and electrical bits--mostly nuts, bolts, and washers of various flavors. If you've got a good one I missed, please do link it in the comments.

If you're interested in making your own and want some guidance, Mother Earth News has a nice tutorial.

Most cell phones are provided with a very basic wall-wart charger, and you usually have to pay extra for a proper charging dock. The bundled charger is often unsightly in use, being just a transformer with a cord strung out to an end table or something where the cell phone rests. If you have a cat who likes to chew through cords, as I do, this can be more than just inelegant--it can be totally impractical. It's also a good project if you just hate, for aesthetic reasons, loose power cords strung out across the furniture.

A similar product is for sale at ThinkGeek, and that's where I got the idea. The nice thing about my version is that it requires no tools to mount or demount, being suspended by the plug on the charger itself. So you can quickly move it around to whatever outlet you want or take it with you when you travel. Plus it costs all of nothing to build.

J Miller shares video of the maiden voyage of his rocket built from the plans in MAKE Volume 15. The reaction to the lack-of-rocket-return here is genuinely priceless! And in case you're curious, yes, it was sucessfully recovered. Definitely a good idea to use a very wide open space for testing :)

Compressed Air Rocket  Volume 15, Page 102

More about the Fire Piston Kit

My friend Heathervescent hipped me to this introductory Turbo Pyro kit from Skylighter. The kit supplies what you'll need to make your own fireworks, including a 206 page eBook that guides you through making ten different fireworks: from tube sparklers to bottle rockets to aerial shells to something called a "Flying Fish Fuse Mine". I've skimmed through the eBook and it looks thorough and professionally done. It has a number of embedded videos in it, which should be pretty helpful.

I've only had moments to scan the contents of the boxes, but they include a lot of paper tubes, charcoal, potassium chlorate, clay, potassium nitrate, sulfer, and other compounds (this endeavor involves making your own gunpowder), a few different kinds of ignition fuses, a bunch of mysterious custom tools for packing the fireworks, a digital scale, mortar casings, a large mortar tube, and more. You have to supply some sieeves, trays, measuring spoons, an electric coffee mill, tape, glue, safety gear, and a few hand tools.

I'm going to try the simplest projects first, hopefully in time for the 4th of July. Then, if all goes well (and I have the same number of fingers as I'm typing with right now), I'll put together some of the big flying stuff and head out to the desert to fire them off.

You can sign up here to be notified when the next batch of kits is available:TurboPyro

Their blog is pretty cool too, I had no idea people had taken things to this level!

My dad recently took a minor tumble on his motorcycle. He's fine, but the bike was banged up a bit, including a bent brake rotor. Consensus among his buddies in the Magna Owners of Texas was that the rotor would have to be replaced, but of course they're pricey, and since the rotor was "shot" anyway, Dad figured he might as well try to straighten it and see what happened.

Here's what he did, in his own words:

Since I had mounted the tire/wheel on the axle in my vice to polish the wheel, it was a simple matter to rig up the "feeler" shown in the first picture to check out the rotor flatness. Just a piece of copper wire about AWG 7 to 9 or thereabouts -- I had in my electrical junk box. With a light behind the setup, one can use the reflection of the end of the wire from the rotor surface to obtain a very sensitive indication of warp when one spins the tire/wheel. Brought it back to planar using a soft face (brass) hammer. Go slow, it takes some time. "Sneak up on it" by whacking gently, measure, whack a little harder, measure, etc. until it yields just a bit.

Then, concerned that the rotor needed to be flatter than he could detect with the naked eye, he rigged up a second jig to test it:

Assemble your very own HD home theater projector using these DIY kits from G&P Optoelectronics. Combine the optics, housing, lighting, and electronics bundles and with luck you'll be watching your favorite episodes of Make: Television in glorious 1280x720 HD in no time.

DIY HD projector for under €499 [via slashgear]

Scoochmaroo shares this recipe for basic sunscreen free of the umpteen additives used in commercial varieties.

Sunscreen is intended to shield your skin from harmful UVA and UVB rays. These can cause premature aging, and more tragically, skin cancer. But commercial suncreens often involve more nasty chemicals than necessary.

By making your own sunscreen, you control exactly what goes in!

More about the Desktop Onager

I've seen this thing referred to as an "Ocean Mat," a "Prolong Knot," a "Ladder Mat," and a "Sailor's True Love Mat." Whatever you want to call it, it's a noble expression of the manly art of knot-tying, and this tutorial at the UK's Scullion Enterprises will show you how it's done.

More:

• Rope bending
• Make knots - Alaska museum of fancy knots
• How-To: Tie a double fisherman's knot
• Star knot tutorial
• Val ties the canoe
• The forgotten Zeppelin knot
• Knot reference wallet card

The "LED Light Brick" project in MAKE, Volume 18 has generated lots of good feedback for us, so we went back and asked Alden to explore a few variations on the theme of the brick casting itself, how you might be creative with it. This article is the result. Be sure to check out the original piece in MAKE, Volume 18, and also the on-line supplement containing specific casting instructions. --SMR

From the pages of MAKE

Some Experiments in Mold Making

A lot of the fun of the Light Brick is trying out different molds. Some very different effects can be achieved depending on the mold you make. This post explores some mold making options and experiments.

The Arkansasridgerunner pioneers the world of shipping chic with this sensible wine rack built from FedEx tubes. I do believe this would go quite nicely with my packing-peanut chaise lounge!

More about the ArduPilot

A former chemistry teacher of mine provided a great definition of "pyrophoric:"

[It] means that if you playfully squirt some at your lab mates, they will burst into flame.

In other (less amusing) words, a "pyrophoric" substance is one that ignites spontaneously on exposure to air.
Pyrophoric iron, however, isn't as dangerous as that makes it sound, especially in small quantities.

Basically, the oxidation of iron is so vigorous that it can cause very finely divided iron metal to become incandescent. Amazing Rust has a great tutorial on how to prepare finely divided iron by thermolyzing iron oxalate, a yellow powder that can, in turn, be prepared by a simple reaction between two common chemicals.

Uber-bender Pete Edwards of Casper Electronics shares his recipe for cooking up some tasty mods for Casio 'SA' series keyboards -

This is an engineered modification which works on most of the Casio SA series ( SA-1, SA-5, SA-7, SA-8 etc). There will be an Amplifier chip ( No AN8053 ) common across the SA series and a mask programmed CPU which will be made by OKI and have the part No M6387-xx where xx is the variant for the specific keyboard it is installed in, in the case of the SA-5 it is M6387-16. The different variant number accommodates different key / button layouts of the keyboard it is fitted into, the PCM sounds however remain the same. There are 5 interesting modifications that can be easily fitted:

1) Pitch Shifting
2) Power Crash
3) 5th's Switch
4) Glitch Randomizer
5) Filter/ Feedback Adjustment

I am just starting to learn Morse code and got a brand new key from American Morse Equipment. Most keys need to be mounted to hold them in place while the operator is dah-dit-ing. Keys are mounted on a heavy platform, or fastened to a radio. And some keys are worn on a leg strap. As a lady operator, and fashion designer, I wanted something cuter to keep my key on my leg, so here it is -- how to turn a standard leg strap into a cute Morse code key leg strap.

Materials:
* 1 yd 2" wide satin ribbon
* 1 yd 3/8" wide patterned ribbon
* 1 yd 3" wide lace
* 2 spools of thread (to match patterned ribbon and lace)
* scissors
* a small amount of tulle (an 8" x 8" square will work just fine)
* a small amount of organza
* pins
* screw driver
* measuring tape

* key
* leg strap

1. Using the measuring tape, measure around your leg where you'd like to wear the strap. Subtract ½" from this measurement and cut the lace and patterned ribbon to this length.

2. Using a sewing machine, straight stitch the edge of the ribbon 1 1/8" in from the edge of the lace.

More about the Fiber Optics Kit

The latest addition to my feed reader is There, I Fixed It, a site collecting fantastic and hilarious examples of jury-rigging in daily life. My favorite so far is the point-of-use hot water heater shown above, but the "Franken-chair" has to take a close second. Thanks to Melody for steering me to it.

AIDG is a NonGovernmental Organization (NGO) that helps provide low technology solutions to help address environmental and health needs to people living in communities without great access to the systems that many of us consider requirements.

Here are a few of their water-based initiatives:

Solar Hot Water:

XelaTeco, with support from AIDG's wonderful interns, recently installed a solar water heating system and water tower for La Guarderia, a childcare center in Llanos del Pinal, Guatemala. La Guarderia was started by two non-profit organizations, Pop Wuj and Jóvenes Juntos, who saw the need for daycare and after school homework assistance in a community plagued by poverty, domestic violence and alcoholism.

Jóvenes Juntos requested the hot water system to promote healthy hygiene practices amongst the children served by center, particularly in the cold winter months. The presence of hot water is expected to reduce the occurrence of skin ailments, such as scabies and other rashes. This segment of the project was funded by AIDG.

Ram Pump:

As the water runs downhill from the source to the ram pump, it gains force and velocity. When this velocity reaches a determined point, the water closes a valve in the ram pump known as the "impulse" or "waste" valve. The force of the water against the now closed impulse valve causes pressure to build inside the pump. The water sends high-pressure shock waves in all directions (the "water hammer," or "ariete" in Spanish, from which the pump gets its Spanish name, "Bomba de Ariete"). These shock waves open another valve, the delivery check valve, and water squirts through reaching altitudes of up to ten times greater than the vertical distance from the water's source to the pump. An air vessel installed in the pump acts as a kind of regulator which keeps the flow at the top steady, instead of delivered in bursts, as the pump internally functions

Sand Filtration:

Properly managed sand filters remove 96%-98% of water borne pathogens such as E. Coli and Giardia, producing a positive significant impact on the health of target users. The greatest effect is expected for young children, who are extremely susceptible to diarrheal diseases caused by exposure to contaminated water. Diarrheal disease causes approximately 2 million deaths per year among children in developing countries.

The World Health Organization has some good documentation on sand filtration technology.

To find out more about AIDG, check out their blog and their photos.

Built from plans in Make Magazine with a couple mods. Made from a sprinkler valve and PVC (and of course duct tape!), compressed air fires the rocket high into the sky. Our rocket is make of the foam cylinders you wrap around hot water pipes (and duct tape!).

Here is a printable pdf of the rocket body and cone. Check out the article in the digital edition of MAKE, Volume 15.

My Dad got a shiny new red tractor the week before Father's Day, which created a great opportunity for an easy, inexpensive, handmade gift: I bought a classic little red toolbox, to match the tractor, and fitted it with eight 3/4" ring supermagnets on the bottom to make it stick to the fender. There's a rubber washer between each magnet and the bottom of the toolbox, to cushion the magnets, each of which is secured using a 3/4" automotive panel fastener--basically a barbed plastic push fastener.

Inserted through the hole in the magnet, through the rubber washer, and through a 1/4" hole drilled in the bottom of the toolbox, the panel fastener secures everything in place. The head of the fastener also makes a nice black plastic "foot" on the bottom of each magnet, which protects the finish on the tractor from marring against the magnet, without being so thick as to block magnetic attraction.

More:

• How To: Father's Day Mini Toolbox
• HOW TO - Penrose Stamps

From planetwrite in the MAKE Flickr pool, This ought to scare the daylights out of your average babysitter!

Michael Jackson's death caused radio's roboprogrammers to take a back seat for a while. Increasingly, over the past few decades, broadcast radio has ceased to be a local affair. As the FCC regulations on local ownership of media outlets has faded towards corporate behemoths, radio programming more and more these days is done by databases and distant decision makers. For those of us who remember real radio dj's who made personal decisions about what song would come next, this has driven us more towards our own music collection, rather than being stuck listening to the corporate drivel. Pandora and Last.fm are okay, but they lack the personal touch.

With Michael Jackson's death announcement, the clacker driven music machine was taken off line, if only for a few hours and only on a few stations. Human beings again ruled the airwaves of some radio stations.

"It's a good reminder of what live radio can do, of the role that radio can play in bringing a community together,'' said Scott Fybush, editor of Northeast Radio Watch in Rochester, N.Y.

Many stations no longer have live announcers, using canned voices for part or all of the day, and so can't react to a major news event, he said.

DJ Deirdre Dagata, 39, has been working at Mix 98.5 part time since May, after being replaced at Kiss 108 by recorded programming the month before. And yesterday, she was back in action for the biggest radio day in memory.

Dagata was in constant motion during her 9 a.m. to 2 p.m. shift. Sitting in an elevated office chair in front of four computer screens, she punched blinking phone lines, tapped on keys, and slid knobs - simultaneously editing recorded calls and fielding a steady stream of new ones from listeners who wanted to share stories about Jackson.

Back in the day, I recall listening to the radio knowing something unique was happening. The radio announcers had their own tastes in music, and they helped to create a following around their musical tastes. Sometimes there was dead air as the dj missed the cue for a variety of human reasons, some more innocent than others. This caused me to volunteer at and work at several radio stations in the 1980's and 1990's. I actually chose my university because I liked the on air feel of the campus radio station, which turned out to be a very influential organization for me. At the station, I did on-air work, production of public service announcements, newscasts, dj training, and eventually became Program Director. The audience's active listenership of the music and programming was exciting to be involved with.

Back then, radio was a public service to be provided to the community, not just a marketing opportunity. Almost radio programming was done with people at the microphones, nearly always they were playing actual records, tapes or cds. Even the commercials were created in-house, except those for national campaigns.

Do you miss real radio? There are a bunch of college radio stations around, and most of them depend on the student body and sometimes local community members to create their programming. With web streaming, it is possible to listen way beyond the broadcast range of your favorite station. WERS in Boston plays a good mix curated by communications students. KEXP in Seattle has a wonderful mix of live performances and genuine djs choosing the music they play. Transom and Youth Radio are helping to cultivate the new voices of radio that we need. Public Radio Exchange has a channel on XM radio, and features a mix of voices that you may not have heard before.

With podcasting and the great suite of computer software and hardware available for free, just about everybody has the radio recording studio in their laptop, desktop, cellphone and digital camera that I had in my bedroom as a high school kid. If you want to broadcast, you may want to build your own transmitter. Sending out your homebrew radio programming out to your house or close neighbors could be a neat experience. You could record some short pieces like songs, jokes, or seque buffers, drop them into your music library and set your music player loose, sending your personalized radio program out to the transmitter.

Radio used to be a LOT of fun as a listener and programmer. Now the tools are much easier to get and use for us regular folks. Hopefully, the corporations will lighten up on their centralized programming and return to the human touch of radio, but even if they don't we can realize that we can choose what radio we listen to or create. If you have any stories of making your own or listening to real radio, pirate or otherwise, tell us in the comments.

Well, classes are finally over, and people like Charles can finally settle down to the important work of...extreme grocery carting:

While I seem to be in "build season" mode year-round, it is during long breaks with little in the way of academic or life obligations that I get the most done. Last summer, I began work on LOLrioKart and built Überclocker, Pop Quiz 2, and Nuclear Kitten for Dragon*Con.

So, for many of us, summer has arrived. Whether you are a teacher, student or neither, you likely have some essential experiment, project, mission or other task for the curious long days ahead. Fill us in through the comments, and point out some links so that we can see your winter and spring dreams come to summer's reality.
[via MITers]

C.K. Sample III (author of PSP Hacks) just posted his technique for making an iPod tripod mount; he used the form-fitting packing material that came in the box as the basis of the holder. You could probably extend his technique to a lot of other gadgets, too:

I was thinking about this tonight, and remembered the nice little white holster of plastic that came in the box of my iPhone 3GS and cradled it so nicely. So, I took that, took a 3/16 drill bit and drilled a hole where the camera is and another where the recycle symbol was on the back of the plastic holster. I shaped each hole slightly wider using the drill. The recycle symbol hole was just the right size to be a bit tight for the mounting screw, so that the screw itself could tap its own path tightly in the plastic hold...

How to make a cheap tripod mount for the iPhone 3GS

Instructables user thatoneguydavid shows us how to make an ultra-mini boiling pot from a beer can for backpacking. He also put together a 1 oz. spice kit with which to cook.

Build It Solar has a great collection of solar DIY projects, including stills, cookers, food driers, and water heaters. But the gem of their solar-distillation collection, for my money, is this paper, from 1985, by Horace McCracken and Joel Gordes. It's unformatted ASCII and black-and-white GIFs, but it provides a better review of the various designs of solar stills, and the theory that informs their design and operation, than anything else I've found in the tubes.

From the pages of MAKE:

If you're interested in all things solar, be sure to check out Parker Jardine's Solar Power System Design in MAKE 14.

More:

• The Watercone
• Make a pizza box solar oven
• HOW TO - Make your own solarbag

Steampunk devote slickshughes can only wear his goggles on his head because of his glasses, so he spruced up his forehead-only pair with some LEDs. Reminds me of The Fly.

Light up goggle mod