Making Magnetite Nanocrystals

May 8, 2010 by Caleb Kraft 11 Comments

Unlike many chemistry projects we post here, making magnetite nanocrystals doesn’t require anything that can’t be found in a local grocery store. All that is required is oil, vinegar, crystal drain opener, and rust. We don’t recognize the specific brand of drain cleaner that they are using, but we’re sure that you could find one with the same ingredients. Magnetite nanocrystals are used to remove arsenic from water. If you are in the USA or most of Europe, that’s not a big concern, but it can’t hurt can it?

[via Make]

Cornell Final Project List

May 8, 2010 by Jakob Griffith 6 Comments

Looking for an interesting project to do using an Atmel Mega644? Students at Cornell University have got you covered. They were required to choose, design, and build a project using the microcontroller; and this year is quite promising with video object tracking, the always popular theremins, helicopters, Potentiostats, even Pavlovian conditioned mosquitoes, and more.

Of course all the previous years are included as well, making over 350 projects total.

[Thanks Bruce Land]

5×2 Patch Board

May 7, 2010 by Mike Szczys 16 Comments

Sometimes we want to sit on the back porch, crack a beer, and do some prototyping. Other times we’d like to do the same but on the couch in the livingroom. To that end we added a 5×2 pin to 10×1 pin patch board to our solderless breadboard.

The 5×2 pin form factor is pretty common, used as an AVR programming header, on development boards like the Dragon Rider 500 and the STK 500, and in small prototyping devices like the Bus Pirate. We like the freedom of using IDC cables as interconnects and that’s where this board comes in. Now we can patch into the IDC cables yet still quickly disconnect them when moving to a different prototyping location. Check out the PCB artwork and this handy device in use after the break.

Continue reading “5×2 Patch Board” →

Reuse That PDA As A WRT Terminal

May 7, 2010 by Mike Szczys 21 Comments

[Michu] used his old Palm IIIc to make a serial interface for his OpenWRT router. It’s a matter of cracking open both the router and the Palm device, then connecting the TTL lines from the router to the MAX 3386e level converter chip inside the Palm. From there, Pocketterm can connect to the router’s serial terminal.

A lot of us have old electronics lying around that work perfectly well. It’s nice to find hacks that make them useful again.

[Thanks Isama]

Toner Transfer Explained Step-by-step

May 7, 2010 by Mike Szczys 33 Comments

[Tanjent] send us a link to his tutorial on the toner transfer process for fabricating circuit boards. We’ve seen a lot of these in the past, but we liked how his is straight to the point while also sharing several tips and options along the way. Notably, he ”tints” the copper clad before trying to adhere the toner to it by swabbing on a bit of etchant. His reasoning for this is that the toner has more trouble sticking to the shiny copper. Just a bit of etchant will pit the surface and let the toner stick better.

He’s still using paper as a medium and not printing toner powder directly to the copper clad. His paper of choice is HP Brochure Paper while we use glossy pages from the union newspaper. But like us, he does use copper chloride as an etchant, which you can learn to make yourself. We’re still looking for a definitive solution for disposing of this chemical. We’ve been using the same batch for years and recently it’s turned cloudy with impurities. If you’ve got disposal tips let’s hear them in the comments section.

Hand Made Manipulator Arm

May 7, 2010 by Mike Szczys 32 Comments

We’re pretty used to seeing CAD used in the design process for most things. It’s a bit of a shocker to come across a project this involve, and this well executed, that didn’t use CAD.

[Anton] spent 100 hours building this manipulator arm by hand. He made the parts by drawing them on styrene and cutting them out with scissors. He has started building version two with AutoCAD but from what we’ve seen in the video after the break, improvements on the original design will be minor. The speed and fluidity of the servos with added magnetic encoders makes for a graceful robotic dance; we’d love to be its chess partner. Continue reading “Hand Made Manipulator Arm” →