This beautifully crafted grinder would make any machining enthusiast salivate.It features a fixture for holding your work at any angle or orientation to the grinding wheel but the slotted bed also allows for other attachments to be used. Two of the examples shown in this highly detailed (machine porn) writeup include sharpening bits and light surface grinding. There’s not much more to say because the pictures speak for themselves.
[Thanks Bud]
[Mpark’s] propeller controlled Etch-a-Sketch is well built and very accurate. He was inspired by the Step-a-Sketch project and he’s carried that design through to a stunning conclusion. The driver board was built around a Parallax Propeller P8X32A microcontroller. But this isn’t just a serial controller board for connecting the hardware to a PC running CNC software. He’s included TV out and a keyboard port so that programming can be done on the chip itself.
In the video after the break you can see how precise the plotting is on the Etch-a-Sketch. It is well mounted but also benefits from some software compensation for the toy’s imprecise controls. [Mpark] has also included an erase function that tilts the frame upside-down a few times. This is used not only to erase a drawing but to hide the line created when moving the stylus into its starting position.
Continue reading “Propeller Takes Step-a-Sketch To A New Level”
[youtube=http://www.youtube.com/watch?v=XJ7gD0nH-xA]
If you think there’s never enough computerized numerical control in your life perhaps the pizza plotter should be your next project. This is a large 2-axis machine that shoots pressurized sauce onto a pizza crust. It’s a food-grade RepStrap and appears to use a garden sprayer as a reservoir. They learned their lesson when a loose hose clamp sprayed sauce around the room. We’re thinking this is a bit of reinventing the wheel as pizza-making factories but it’s fun nonetheless.
[Bart] built a giant laser etcher from scratch. One of his first test engravings included the Hackaday skull-and-wrenches on a polished granite floor tile (we love it when people do that). He used an XMOS controller and Mach3 CNC software to handle the device. With just two axes to worry about this seem like an easy project. The difficult bit is controlling, cooling, and focusing the laser. Oh, and if you screw up, you could be blinded, burned or horribly maimed. But if you start from the beginning you’ll see that [Bart] knows what he’s doing.
[lucassiglo21] let us know about his finished 3 axis CNC (Translation via Google). While home CNCs are nothing new, we really liked this masterpiece. The CNC is entirely custom, from the electronic control boards (connected to a PC via parallel port) to the physical mill (with an end result of 30x30x15cm workable area). Our favorite part is the use of screw/band clamp zip ties to hold the Dremel – a true showing of hacker geekyness. For those who haven’t seen a CNC drill a circle before (and honestly, who hasn’t?), check a video after the break.
[Nophead] started the year off by successfully extruding acrylic using a RepRap machine. The problem when working with this material is that when the hot ooze hits the cold air the printed material tends to warp, badly. [Nophead] raised the ambient air temperature around the part being extruded by replacing the bed of the RepRap machine with a heated aluminum plate.
We took at look at his build details for the hotbed. The plate itself is aluminum that he had milled by a machinist friend of his. It looks like the heat is produced by a network of power resistors bolted and soldered to the bottom of the plate. The original idea was to produce a controllable SMT soldering platform. Unfortunately this heating method doesn’t have the power needed to raise the temp quickly but that failure turned out to be a RepRap success.
[Chris] is getting his feet wet with Computer Numerical Control starting with an Etch-a-Sketch interface. This is a great way to start out because the really tough parts of the project are already inside of the toy. He’s replaced the two white knobs with stepper motors and connected them through a mosfet network to a PIC 16f84a. The PIC then gets its commands from a computer via the parallel port.
A video of the CNC machine can be seen after the break. He needs to add a frame to increase the precision of the images drawn but this first attempt is pretty good. We prefer to have the computer in charge of the design because controlling an Etch-a-Sketch with a mouse doesn’t make our drawings any better. Continue reading “Step-a-sketch”
