A Papercraft Resistor Calculator From Adafruit

April 27, 2012 by Brian Benchoff 22 Comments

The Adafruit blog just posted a neat papercraft resistor calculator. If you haven’t yet learned the horribly offensive mnemonic for resistor color codes, now’s your chance to have a cheap and portable resistor value reference.

This papercraft resistor calculator is the latest in the family of Circuit Playground tools that include a fabulous electronic reference app we reviewed some months ago. Instead of an Android or iOS device, the papercraft resistor calculator runs on its own mechanical computer; a series of four printed disks and some paper fasteners.

If you’d like to print out your own resistor calculator, Adafruit put up the PDF on GitHub and posted the Illustrator file on Thingiverse for easy editing. It’s not the old-school cool of a slide rule, but we could easily see this resistor calculator being useful if you’re ever lucky enough to teach electronics to children. At least then you won’t have to share that offensive mnemonic.

Sand Casting Motorcycle Cases

April 25, 2012 by Caleb Kraft 12 Comments

Sand casting has been around since, well, since a really really long time ago. For thousands of years, people have been pouring molten metal into finely crafted sand casts, and there’s really no reason that someone can’t do the same thing in their garage or workshop today. This article covers the process of sand casting new case parts for antique Indian motorcycles. In this instance, the parts were not only very difficult to find, the author also wanted to modify the design completely.

Though there are a few terms that pop up with which we’re unfamiliar, the process seems pretty straightforward. You build a model of what you want, you create the sand cast from the model, you fill the cast with molten metal. Done. In some cases, depending on the level of precision needed, you may need some machining done afterward. However, in many cases things don’t have to be quite so exact.

[via Matthew Van Arsdale]

Homebrew Solder Pot Is Too Dangerous Even For Us

April 25, 2012 by Brian Benchoff 58 Comments

[rue_mohr] is building a hexapod robot, and that meant he needed to tin a whole bunch of ribbon cables with solder. Using a soldering iron for this task would take far too long, so he built a homebrew solder pot to tin all those wires quickly. While [rue] was able to get solder on all those wires quickly, we need to question his method – he used a halogen light and reflector to melt all that solder.

The build began with a recycled halogen light fixture. After taking apart the entire assembly, [rue] reassembled it into something resembling a solder pot; a concave reflector and halogen light bulb sit perfectly flat on the table, ready to accept pieces of solder.

After throwing the switch and putting a few bits of solder in the reflector, the solder pot surprisingly worked. [rue] was able to quickly tin his ribbon cables, and the halogen bulb and reflector didn’t break yet.

This is one of the least safe solder pots we’ve ever seen – the bulb could easily explode, and melted solder could come pouring out of the reflector at any time. [rue] is aware of the safety implications and make sure to wear a pair of goggles. If it works though, we really can’t complain.

Check out the video of [rue]’s solder pot (with an awesome temperature indicator light right in the middle of a pool of solder) in action after the break.

Continue reading “Homebrew Solder Pot Is Too Dangerous Even For Us” →

PiP-Boy 2000 Build Goes For Function Over Form

April 24, 2012 by Caleb Kraft 14 Comments

[Daniel] wrote in to tell us about his PIP-Boy 2000 prototype. While most PIP-Boy remakes we’ve seen tend to be focusing more on the aesthetic side, like a prop, [Daniel] is attempting to make a functional one. He has included a GPS sensor, RFID reader, and radiation detector in his build but did choose to stick with the familiar PIP-Boy visual theme in the menus. He has a very long way to go if he wants it to do everything the PIP-Boy from Fallout did, but his list of semi-functional features is growing steadily.

Currently there are the basic functions of:

automapping and waypoint navigation
external PC interface
inventory status and item recognition (using RFID)
player experience (adds experience as you go to new locations)
ambient radiation
screensaver

Let us know when you get that sucker to stop time [Daniel]

Printing PCBs On A Junked Epson Printer

April 24, 2012 by Brian Benchoff 28 Comments

When it comes to making PCBs at home really quickly, there’s not much to improve upon with [Ryan]’s bodged up Epson printer that prints an etch mask directly on a piece of copper clad board.

Like most of the direct to copper PCB printer conversions we’ve covered ( 1, 2, 3 ), [Ryan]’s build relied on an Epson printer and Mis Pro yellow ink. The Mis Pro ink is one of the most etch-resistive substances that can be shot out of an inkjet printer, and Epson printer cartridges use a piezo pump that is perfect for squirting ink out on command.

After tearing the printer apart and lifting the print head a bit, [Ryan] needed a proper feed system to control where on the copper he was printing. He managed to make a board carrier out of a sheet of aluminum. By taping down the copper clad board, everything seems to work phenomenally.

After the break you can check out how fast [Ryan] can print out a fully etch-resisted PCB. It’s not improbable that he could produce a few dozen boards an hour; something our toner transfer PCB production method would kill for.

via makezine

Continue reading “Printing PCBs On A Junked Epson Printer” →

A 3D Pantograph

April 19, 2012 by Jeremy Cook 17 Comments

It seems that there is no end to ingenious woodworking tools, such as this 3-D Router Pantograph from [Woodgears.ca]. The pantograph, a design using linkages to trace and scale drawings, may have been invented in the 1600s, but if we were honest, most of us haven’t heard of this device. This particular pantograph is able to trace letters or other stencils in three dimensions by pivoting about an additional axis.

If you’re wondering where to get these stencils, they’ve got you covered with an online stencil generation tool. However, if you want to make even more detailed stencils, we might recommend using a free drafting tool such as Draftsight (here’s a review), or Sketchup.

[Woodgears] gives a good explanation of how it’s made in the video after the break. You can also buy plans for it if you want templates to use to cut everything. Continue reading “A 3D Pantograph” →

Android App Review: ADSdroid Gives You Every Datasheet, Ever

April 18, 2012 by Brian Benchoff 34 Comments

A few months ago when I reviewed the Android electronic reference app ElectroDroid, I made the offhand remark that a front end app for alldatasheet.com would be a killer mobile electronic reference app. [András Veres-Szentkirályi] accepted my challenge and built ADSdroid, the unofficial Android app for alldatasheet.com. You can check out my complete review after the break.

Continue reading “Android App Review: ADSdroid Gives You Every Datasheet, Ever” →