“A laser harp is basically a big frame resembling a real harp. There are no strings. Instead, beams of laser light are projected from the bottom of the harp. These beams strike light sensors at the top of the frame. When something (a hand, foot, etc.) blocks the beam, a note is triggered on a synthesizer or some type of tone generator. Theoretically the harp could control anything but I’m interested in its musical possibilities.” Here’s how to make one! [via] Link.
In MAKE 01 we showed you how to make a “gauss rifle” – A linear accelerator for studying high-energy physics costs around $5 billion. But you can make one for about 30 bucks with four strong magnets, a wooden ruler, some plastic tape, and nine steel balls. Here is Daniel’s photo set on Flickr of the one he’s making… Link.
Andreas writes “I don’t know how, but late at night I got the idea that I wanted to covert my new 3D cell Mag-Lite to a handy photo-lamp. Next morning I dug out some 250 GSM paper and some adhesive foil I’ve been saving for a worthy project and whipped up a quick ghetto-lamp…It’s not all that powerful, but it’s great for macro shots and softening hard shadows, and it’s very portable. Think of this as a beta version, I’ll likely improve the design a bit once christmas is over. The basic concept is sound, I think there’s potential for more if I sort out a proper parabolic reflector for it.” Thanks Jason! Link.
Jonathan designed a great printed circuit board router, he writes – “Printed circuit boards are usually manufactured by chemical etching (with iron (III) chloride or ammonium persulfate, for example). This is not very practical if only a few boards are necessary, because these etchants are messy and somewhat dangerous. PCBs can also be manufactured by “mechanical etching,” in which a trace is “etched” by milling away the copper along its perimeter. This requires software to generate a toolpath from the layout and a small CNC mill or router. Lots of companies make routers for PCB fabrication, but they are unjustifiably expensive so I decided to build one.” Link.
Here’s a detailed log of how to build a utility trailer. Includes a free AutoCAD drawing, materials list, parts list, as well as lots of pictures. Glen writes “I needed a trailer to haul around a snowmobile so I decided that I might get better use out of a general utility trailer instead of a snowmobile trailer. I checked the local trailer retailers and found that the going rate for a 5′ x 10′ utility trailer was around $1,300 Cdn. The trailers weren’t very strong and were made mostly from light angle iron. Always looking for a good project, I decided to build one instead.” Link.
From the folks who brought us the homemade sheet-rock lifter – cement casting with forms…“I designed these window sills as a DIY solution as to what to do with 200 plus windows we had to rebuild, this saved us from having to restore the brickwork that was damaged from years of neglect and weather. The most obvious solution would have been to restore the brick and slap a piece of wood on top. Instead I created a mould that was fastened to the wall and the sills were cast in place.” Thanks Frank! Link.
Here’s another great how to on converting an ATX power supply to a lab power supply, Abizar writes “Computer power supplies are US$15 but lab power supplies are US$100+. By converting the cheap (free) ATX power supplies that can be found in any discarded computer you can get a phenomenal lab power supply with huge current outputs, short circuit protection, and very tight voltage regulation.” Link. See previous.
