Gizmodo: coasters

DIY Smart Coaster Lets You Know When Coffee Is 'Just Right'

Jack Loftus — Sun, 23 Nov 2008 18:30:00 EST

As a cream and sugar kind of guy—that's a "regular" to we Yanks in Boston—getting a cup of coffee that's consistently at the "right" temperature is a crapshoot at best. If there's not enough cream, I'll scald myself with a fresh cup. Other times there's not enough; I'll get sidetracked, and then go back to my cup for a disgusting gulp of cold nastiness. The cream throws me off. It ruins my calm, and plays havoc with my coffee temperature. I need something that knows when my cafe is a the right temperature. Popsci, thankfully, has delivered this evening with a DIY "Smart Coaster" they've made using an old shoe polish tin. The work week starts tomorrow; this couldn't have come a moment too soon.

TIME: 3 hours
DIFFICULTY: easy

PARTS

* LM324N (Mouser #512-LM324N)
* Thermistor (I used an obsolete thermistor from Electronic Goldmine #G1929 for my circuit.) Try this one from SparkFun Electronics #SEN-00250
* 1K resistor (Mouser #660-CFS1/4C102J)
* Red LED (I used a salvaged LED for my circuit.) Try this one from Mouser #696-SSLLX5093HD-5V
* 10K resistor (Mouser #660-CFS1/4CT52R103G)
* 10K potentiometer [I used a salvaged pot for my circuit.] Try this one from SparkFun Electronics #COM-00104
* 3.7V battery (SparkFun Electronics #PRT-08818)
* Scrap wire
* Round flat-top metal container (I used a salvaged Kiwi Brands shoe polish container — just to prove to some of you that I do know shinola.)

STEPS

1. Clip off the unnecessary legs from the LM324N IC: keep pins 1, 2, 3, 4, and 11.

2. Attach the thermistor to the inside of the metal container's lid with some tape. Be sure to insulate both of the thermistor leads.

3. Drill a hole in the side of your metal container for holding the red LED. Insulate the bottom of the metal container with some scrap paper or 2mm hobby foam.

4. Follow our schematic for building the Smart Coaster circuit.

5. Fit the components inside the metal container, connect the 3.7V battery, and close the metal lid. You can easily test your completed project by turning the potentiometer until the LED just turns off (this is roughly equal to room temperature). Now hold one of your hot little fingers on the lid of the Smart Coaster. Within about 5-10 seconds, the LED should turn on. If not, then open up your metal container and carefully reexamine your wiring. If this test result is OK, you are now ready to calibrate your Smart Coaster.

Place your cup of fresh brew on the Smart Coaster and use the 10K potentiometer to adjust the sensitivity of the thermistor. Turn the potentiometer until the red LED glows and closely monitor the temperature of your beverage. When the cup's temps have fallen to your desired drinking level, turn the potentiometer until the LED goes out. Your Smart Coaster is now calibrated for monitoring your future drink temps. Remember, if you change cups or mugs you will have to recalibrate the Smart Coaster. Bottoms up.

See? Easy. And now the mornings will go by *slightly* faster than normal. [Popsci]

Please Insert Drink 5 of 12 to Continue Alcoholism

Erica Ho — Mon, 03 Nov 2008 21:15:00 EST

This hand-sewn floppy disk coaster set will put you back $28 for stain-free coffee-table goodness for the neat-freak nerd. Available in five colors, it'll also make you reminisce for the times you sat there for forty minutes, inserting floppy disk after floppy disk to install Microsoft Office 6.0. At least you won't have to worry about those drink stains when you are sitting in front of the television Election Night, with your ol' friend Jack Daniels, choosing between celebration or consolation. It's a shame they don't cure hangovers for a bright and early day at work Wednesday morning! [Etsy via GeekSugar]

Smart Coasters Differentiate Iced Tea from Hot

Mark Wilson — Wed, 01 Oct 2008 16:20:00 EDT

We know that you probably don't need help figuring out if what you're drinking is hot or cold, but that only makes these Smart Coasters all the more endearing. Essentially a solar cell trapped in waterproof resin, cold drinks light up blue and hot drinks light up red. Full instructions to build your own can be found in The Hungry Scientist Handbook (which runs about $12 at Amazon). But for the less labor-inclined, sticking your finger into visitors' drinks has always been considered a fine gesture of hospitality. [Evil Mad Scientist Lab via boingboing]

Polaroid Coasters Catalog Adventures You Never Had

Mark Wilson — Mon, 22 Sep 2008 13:40:00 EDT

These four retro-exotic beauties had nothing to do with your past exploits, but hey, Polaroid coasters make for great cocktail conversation—especially when they depict semi-tasteful, half-naked women. Rarely do we find coasters worth ruining your coffee table for, but this $12 set is so much hipper than your yellowing IKEA furniture anyway. So go ahead, put that glass right on the veneer and tell us a tale about the lovely Luna from Liechtenstein. We're listening. [GAMA-GO via Nerd Approved]

Pixel Drink Coasters Can Have Any 8-Bit Shape You Want

Jesus Diaz — Fri, 05 Sep 2008 14:00:00 EDT

These pixel drink coasters are made of paper and come in 50-unit packages for $8. Nothing special there until you notice that they have different shapes, which are not actually made at the factory: The coasters come in a single sheet, folded in 50 segments that you can cut in any way you want using the one-centimeter-long square perforations that divide each segment into 110 pixels. The results are beautiful, including an obligatory Space Invaders theme.

According to Technabob, the paper is special, which allows to resist the condensation and even get reused. [25togo via Technabob]

Floppy Coasters Help You Party Like It's 1979

AddyDugdale — Mon, 03 Mar 2008 07:37:11 EST

Designed by Greek geeks-at-heart Supermandolini, these floppy coasters are cute things to stick beneath your drinks. Measuring 3.5" square, a set of six will cost you $41 and make you wish you were still licking your brother at Asteroids all over again. [SuperMandolini]

DIY Smart Beer Coasters Open Up a Whole New World of Drinking Games

Sean Fallon — Wed, 12 Dec 2007 19:40:08 EST

If you can stay sober long enough to build one, a company called Sentilla has developed a DIY "smart" beer coaster that could lead to a myriad of new drinking games for you and your friends to enjoy. The coaster is "smart" in the sense that it can detect when a drink is present and when it is removed, it can communicate with nearby coasters, and it can provide feedback in the form of flashing lights. Plus, it does it all wirelessly. More info and a video of the coasters in action are available after the break.

Besides its more obvious and pointless applications, Sentilla also suggests that these smart coasters can be used to notify a bartender when you are in need of a new drink. Personally, I would rather forgo the seizures and utilize a more elegant solution. Still, if you would like to try your hand at building one, instructions are available on the Sentilla website. [Sentilla via InventorSpot via Geekologie]

DIY LED Pressure-Sensitive Coasters

Travis Hudson — Thu, 02 Mar 2006 07:00:58 EST

This is an extremely simple, but cool idea for a coaster. It works by placing small watch batteries inside an acrylic coaster. Then connect one end of the LEDs to the battery while bending the other LED into an L-shape. Once a full, frosty beverage is placed on the coaster, the other LED contact will touch the battery and light up. Follow the linkage for the detailed instructions, including pictures.

CoasterGlow [MetkuMods]

Circuitboard Coasters

gizmodo.com — Wed, 28 Dec 2005 15:09:10 EST

Remember the kid you picked on back in high school who was winning math Olympiads and what not? You should probably give him a call and apologize this holiday season. In fact, a gift is more appropriate. So why not get him these totally radical circuitboard coasters? Made from REAL circuitboard and not painted on, these coasters are the epitome of geekdom. Now I know this is not the first time you've seen a circuit board used as a coaster. But all hues of the PCBoard rainbow are represented here—amber, green, blue, and others. You can net a set of six coasters for only $20. You'll still get picked on if you use them, but at least you won't have those ugly water rings on your wooden tables.

Circuitboard Coasters [Oh! Gizmo]