Recently I was building a project for a client, who needed an internet-controlled display device. For quick development time and minimal budget, I selected an Arduino Duemilanove, XPort Shield, and XPort Direct from Lady Ada's Adafruit store. Soldered everything together, tested and configured the XPort, everything worked. Then I wrote the necessary code to request data from a web server, that all worked too.

Finally I took the project down to the client's office in Mountain View and set it up...didn't work. I ended up working on the project for about four hours trying to get it running (minus some tricky subnet issues...use increments of 8 bits on an XPort). The client was using lighttpd to serve the display data, and I had been using Apache for testing. HTTP is HTTP, right? It should work on either? It didn't. I set up an Apache server on my laptop and everything worked great...point the Arduino sketch back at the client server, nothing worked. I kept getting "501 - Not Implemented" errors from the web server. If I opened up a telnet session directly to the web server and manually typed in the request the Arduino was sending, it worked.

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I got a batch of cables that had a few bad wires in them, so I needed to test every cable. Checking all the wires with a multimeter was out, so I built this simple cable tester out of a proto board, some headers, an LED, a resistor, and some wire. It just completes a circuit through all the wires in a cable; if any wire is bad, the LED will not light. Simple concept, but it allowed me to test about 300 cables in about half an hour. A video of a few cable tests is below:

This was pretty ugly. I needed to cut a bunch of copper-clad FR4 into thin strips for my LED array project. 144 1/4" strips, to be precise. I wasn't going to use the metal shear at TechShop, since fiberglass is pretty abrasive. I was also worried the pinching effect would wrap copper around the edges and short the two sides. Anyway, I lashed together a mini table saw with a Dremel, diamond wheel, hot glue, plywood, and duct tape. Note the Shop Vac dust removal system. It actually worked quite well, cutting about 120 feet of PCB material and I didn't notice any decline in cutting ability.  Read more»

I decided to make a laundry hamper for my bathroom last weekend. For some reason I didn't want to just buy a hamper, I guess I had specific ideas about durability, shape, and size that weren't available. I also wanted a place to put my towels, and I don't think any hampers have built-in towel racks, and no towel racks have a place to put a hamper. Home Depot is within sight of my front door, so I walked over and wandered the aisles with the familar blank expression of home-improvement pondering. I walked back with 40 feet of 1/2" PVC tubing, various connectors, zip ties, and plastic garden mesh. The result in the photo took about 1-1/2 hours. Aesthetics aside, it definitely works, doesn't take up much space, will never rot or warp like my original wood construction idea, is a little bigger than expected but will be able to hold all my laundry even on a day I wash blankets. PVC tubing is only like $1.89 per 10 foot piece, so it's a cheap construction material and pretty strong in lengths shorter than 3 feet.