How To Build A Mill With Epoxy

March 26, 2019 by Lewin Day 27 Comments

The typical machine tool you’ll find in a workshop has a base and frame made of cast iron or steel. These materials are chosen for their strength, robustness and their weight, which helps damp vibrations. However, it’s not the only way to make a machine tool. [John McNamara] has been working on a CNC mill with an epoxy base, with impressive results.

The molds were designed in CAD prior to casting, ensuring there was room for all required components.

The build is one that could be readily achieved in any decently equipped makerspace. [John] used lasercut steel parts to construct the molds for the epoxy base, with some custom turned parts as well. The precision cut parts fit together with great accuracy, and with proper control of the casting process there is minimal post-processing of the final cast piece required. The mold is built with zero draft angle, and is designed to be taken apart to remove the finished pieces. By using steel, the same mold can be used many times, though [John] notes that MDF could be used for a one-off build.

The base is cast in epoxy, mixed with granite aggregate and sand to create a strong, heavy, and vibration damping material. There are also steel reinforcements cast in place consisting of threaded rods, and conduits for various electrical connections. After casting, [John] has spent much time measuring and truing up the mill to ensure the best possible results from the outset.

It’s an impressive build, that shows that building your own accurate machine tools is quite achievable with the right tools and knowledge. We’ve seen similar work before, too – epoxy really does make a great material for casting at home.

Get Moving With New Software From OpenBuilds

March 23, 2019 by Tom Nardi 16 Comments

If you’re reading Hackaday, you’ve probably heard of OpenBuilds. Even if the name doesn’t sound familiar, you’ve absolutely seen something on these pages that was built with their components. Not only is OpenBuilds a fantastic place to get steppers, linear rails, lead screws, pulleys, wheels, and whatever else you need to make your project go, they’re also home to an active forum of people who are passionate about developing open source machines.

As if that wasn’t enough reason to head over to the OpenBuilds website, [Peter Van Der Walt] recently wrote in to tell us about some new free and open source software he and the team have been working on that’s designed to make it easier than ever to get your creations cutting, lasing, milling, and whatever else you could possibly imagine. If you’ve got a machine that moves, they’ve got some tools you’ll probably want to check out.

“OpenBuilds CAM” is a web-based tool which imports SVG and DXF files and creates toolpaths for all sorts of cutting, whether your machine does the business using a beam of angry photons or a simple drag knife. The resulting GCode can then be plugged into “OpenBuilds CONTROL”, which as you may have guessed, does the actual controlling of the piece of hardware connected to your computer. There’s no worries about vendor lock in here either, CONTROL will talk to any Grbl-compatible board.

But what if you don’t have a board? Well, it just so happens that OpenBuilds offers a very slick new piece of gear they’re calling the BlackBox. This beefy CNC controller includes a laundry list of features that [Peter] says the team is very excited about, including stepper drivers powerful enough to run NEMA 23 motors. As an interesting note, they’ve actually made the enclosure for the BlackBox out of cleverly solder masked PCBs; a fantastic trick we don’t see often enough.

The video after the break shows the CNC router version of “Hello World” using CAM and CONTROL, and should give you a pretty good idea of the typical workflow. If it looks familiar to you, it might be from our previous coverage of LaserWeb, a similar web-based project spearheaded by [Peter Van Der Walt] a few years back. Continue reading “Get Moving With New Software From OpenBuilds” →

An Improved Bed And Custom Wasteboard For A CNC Router

March 19, 2019 by Donald Papp 4 Comments

[Adam Haile] has been spending some time improving his CNC router and his latest change is a custom wasteboard with improved bed support. Not only does the MDF wasteboard have plenty of threaded inserts to make for easy clamping solutions, but [Adam] replaced the frame underneath the board with a new set of aluminum extrusions to provide better support. Originally, there was only support for the edges of the wasteboard, which allowed the middle to sag. While researching the machine’s specs, he was able to recognize and order the exact extrusions he needed from Misumi and construct an improved bed to go with the new board. Should you wish to make your own version, [Adam] provides all the part numbers and CAD files required.

Embedded below is a video showing the machine drilling the holes, followed by surfacing the entire board so that it is flat. Since the bolt heads are well below the surface of the board, and the threaded inserts for the holes are on the bottom, there’s no worry of the tool hitting anything it shouldn’t during this process.

Continue reading “An Improved Bed And Custom Wasteboard For A CNC Router” →

Wood SCARA Arm Gets A Grip

March 14, 2019 by Donald Papp 4 Comments

[Ignacio]’s VIRK I is a robot arm of SCARA design with a very memorable wooden body, and its new gripper allows it to do a simple pick and place demo. Designing a robot arm is a daunting task, and the fundamental mechanical design is only part of the whole. Even if the basic framework for a SCARA arm is a solved problem, the challenge of building it and the never-ending implementation details make it a long-term project.

When we first saw VIRK I in all its shining, Australian Blackwood glory, it lacked any end effector and [Ignacio] wasn’t sure of the best way to control it. Since then, [Ignacio] has experimented with Marlin and Wangsamas support for SCARA arms, and designed a gripper based around a hobby servo. It’s as beautiful to see this project moving forward as it is to see the arm moving ~~ping-pong~~ balls around, embedded below.

Continue reading “Wood SCARA Arm Gets A Grip” →

[Ben Krasnow] Drills Really Small Holes With Electricity

March 14, 2019 by Dan Maloney 21 Comments

Drilling holes is easy; humans have been doing it in one form or another for almost 40,000 years. Drilling really tiny holes in hard materials is more challenging, but still doable. Drilling deep, straight holes in hard materials is another thing altogether.

Luckily, these days we have electric discharge machining (EDM), a technique that opens up all kinds of possibilities. And just as luckily, [Ben Krasnow] got his hands on some EDM gear to try out, with fascinating results. As [Ben] explains, at its heart EDM is just the use of a small arc to ablate metal from a surface. The arc is precisely controlled, both its frequency via an arc controller, and its location using CNC motion control. The arc controller has always been the sticking point for home EDM, but the one [Ben] tried out, a BaxEDM BX17, is squarely aimed at the small shop market. The whole test platform that [Ben] built has a decidedly home-brew look to it, with a CNC gantry rigged up to a water tank, an EDM drill head spinning the drill rods slowly, and an airless paint gun providing high-pressure process fluid. The video below shows that it works remarkably well nonetheless.

While we’re certainly keen to see [Ben]’s promised videos on EDM milling and cutting, we doubt we’ll line up to shell out €2,950 for the arc controller he used. If you have more courage than money, this mains-powered EDM might be a better fit.

Continue reading “[Ben Krasnow] Drills Really Small Holes With Electricity” →

Omni Wheels Move This CNC Plotter

March 12, 2019 by Dan Maloney 12 Comments

We’ve always had a soft spot for omni wheels and the bots that move around somewhat bumpily on them. Likewise, CNC pen plotters are always a welcome sight in our tip line. But a CNC plotter using omni wheels is new, and the results are surprisingly good.

Built from the bottom of a spring-form baking pan, [lingib]’s plotter is simplicity itself. Four steppers turn the omni wheels while a hobby servo raises and lowers the pen. The controller is an Uno with a Bluetooth module for smartphone control. Translating wheel rotations into X- and Y-axis motions was not exactly trivial, and the video below shows the results. Lines are a bit wobbly, and it’s clear that the plotter isn’t hitting the coordinates very precisely. But given the somewhat compliant nature of the omni wheels, we’re surprised [lingib] got results as good as these, and we applaud the effort.

[lingib] reports the most expensive part of this $100 build was the omni wheels themselves. We suppose laser-cut MDF omni wheels could reduce the price, or even Mecanum wheels from bent metal and wood. We’re not sure either will help with the precision, though.

Continue reading “Omni Wheels Move This CNC Plotter” →

Painting With Light And A Little G-Code

March 11, 2019 by Dan Maloney 9 Comments

Most photographs are made in the fraction of a second that the camera’s shutter is gathering reflected light from the scene. But there’s fun to be had by leaving the shutter open and directing light into the camera. Called light painting, it can be as simple as a camera on a tripod in a dark room and a penlight spelling out dirty words – not like we’d know – or as complicated as this CNC dot-matrix light printer.

The first idea that [Jeremy S. Cook] had for this build didn’t go so well. He fitted an LED to the gantry of his 3D-printer, intending to send it G-code representing bitmaps. The idea would be to set it up in a dark place, open the shutter, and let the machine build up the image by rastering through the X- and Y- axes while blinking the LED on and off at the right time. But since the gantry only moves in one axis, he abandoned the printer in favor of his CNC router. He printed a collar to fit the dust collector shroud we previously featured, added a battery-powered LED, and affixed a pushbutton switch to the let the Z-axis turn on the light. It took some tweaking such as adding a translucent PLA diffuser, to get decent images, but in the end it worked. We like the soft look of the floating voxels, which were really helped by the later addition of a Nano and a Neopixel. Check out the build in the video below.

One thing we’d suggest is better reflection control. [Jeremy] used a black platen as a background, but it wasn’t quite enough. We suggest going none more black next time.

Continue reading “Painting With Light And A Little G-Code” →