If you have an old manual lathe, mill, or even a drill press, a digital readout (DRO) is a very handy tool to have. A DRO gives you a readout of how far you’ve cut, milled, or drilled into a piece of work without having to stoop to caveman levels and look down at a dial. Here’s a stupidly cheap DRO for all your machine tools. It should only cost five bucks or so, and if you need it, you already have the tools to manufacture it.
This build is inspired by an earlier build using the same single component – a digital tread depth gauge. This digital tread depth gauge is commonly found in countries that don’t use the US penny as currency to measure the depth of tread on a tire. The throw isn’t that large – only about 27mm – but with a few modifications it can fit on any machine tool.
The modifications include a small bit of metal glued to the back and four tiny neodymium magnets. For the ‘tool head’ of this DRO, only a tiny plastic collar and another deo magnet are needed.
This digital tire depth gauge looks like – and probably is – the same mechanism found in those super cheap calipers from the far east. In theory, it should be possible to extend this modification to those digital calipers, making for a simple DRO with a much larger throw.
The title of ‘maker’ is conventionally applied to the young-adult age group. In the case of 84 year-old Ralph Affleck, a lifelong sawmiller, ‘maker’ perhaps undersells the accomplishment of building a fully functioning sawmill that can be operated by a single individual.
Starting in the trade at the age of 16 under his father’s tutelage, fifty years of working in sawmills saw him still loving what he did as retirement loomed. So, with pen, paper, and a simple school ruler he designed the entire shop from scratch. Decades of expertise working with wood allowed him to design the machines to account for warping and abnormalities in the timber resulting in incredibly accurate cuts.
With no other examples to guide his design — aside from perhaps old style steam-powered sawmills, and newer portable ones that he feels are inadequate for the job — much of the shop is built from scratch with scavenged parts. And, that list is impressive: four hydraulic cylinders from a Canberra bomber, levers from an old locomotive, differentials and gearboxes from a MAC and 1912 Republic trucks, a Leyland engine that operated for 13 years without the need for maintenance, and an assortment of old military and air force vehicle parts. This is complimented by his log skidder — also custom — that would look at home in a post-apocalyptic wasteland. Built from two tractors, it combines three gearboxes for 12 forward and 8 reverse gears(what!?), and can hit 42mph in reverse!
3D printers are all the rage, but there’s still space for more traditional CNC machines. For their Hackaday Prize entry, [Andy], [Tim], and [Chris] are building the Sienci Mill – a simple desktop CNC mill that’s able to cut drill and carve everything from wood to circuit boards.
As far as desktop CNC machines go, it doesn’t get much more simple than this. They’re using steel plates for the rails, NEMA 17s for the motors, and a simple stepper motor driver Arduino shield for the controller. The more complex parts are 3D printed, and the BOM doesn’t add up to much.
Right now, the guys are testing their mill on wood, plastic, and aluminum. With 3D printed parts, they’re also able to test a bunch of different spindles from the ubiquitous router to the smaller Dremel. It’s a great project and should be fantastically cheap when the guys finalize the plans, making this a great entry for the Hackaday Prize.
Several years ago, Iran used GPS spoofing to ‘land’ an RQ-170 Sentinel drone operated by the US military. Why is this interesting now? Because this week Pokemon GO was released. It’s a mobile, augmented-reality game that forces you to walk around your neighborhood to catch Pokemon. Apparently you can capture a Mewtwo if you make it to Area 51, Groudon near any volcano, and Deoxys is aboard the International Space Station. In the next week or two, someone will figure out how to spoof the GPS location on a phone to catch rare and legendary Pokemon. This will happen.
The FR4 Machine Shield is a CNC kit made from a PCB. Yes, the entire machine can be constructed using a panel from a board house. It’s now a Kickstarter. Like other desktop PCB milling machines, the FR4 uses hobby brushless motors (think quadcopters) for the spindle, and features tab and slot construction. It’s a pretty neat little tool we checked out a little while ago
If you ride a bicycle, you have a hand pump somewhere around. Those hand pumps get pretty tiring. Here’s a much better solution. It’s a pneumatic air pump. It will inflate your bike tire with the power of compressed air. But that’s not all… this device will also inflate basketballs, soccer balls, and footballs, all with a simple and easy to use air compressor.
You have to be careful with CNC; it’s a slippery slope. You start off one day just trying out a 3D printer, and it’s not six months before you’re elbow deep in a discarded Xerox looking for stepper motors and precision rods. This is evident from [Dan] and his brother’s angle aluminum CNC build.
Five or six years ago they teamed up to build one of those MDF CNC routers. It was okay, but really only cut foam. So they moved on to a Rostock 3D printer. This worked much better, and for a few years it sated them. However, recently, they just weren’t getting what they needed from it. The 3D printer had taught them a lot of new things, 3D modeling, the ins of running a CNC, and a whole slew of making skills. They decided to tackle the CNC again.
The new design is simple and cheap. The frame is angle aluminum held together with screws. The motion components are all 3D printed. The spindle is just an import rotary tool. It’s a simple design, and it should serve them well for light, low precision cuts. We suspect that it’s not the last machine the pair will build. You can see it in action in the video after the break.
For those of us unfamiliar with the process a machinist would go through to accomplish such a thing, the video is extremely educational; it can be sobering both to see how much design work happens before anything gets powered up, and just how much time and work goes into cutting and shaping some steel into what at first glance looks like a relatively uncomplicated part.
We had a chance to talk to Matthew Hertel of PocketNC at the Bay Area Maker Faire this year. During the conversation, he answered some questions I’d had about the project since I saw it on Kickstarter, and told a cool story while he was at it.
When the Pocket NC 5-axis Tabletop CNC Mill KickStarter came out, I immediately chocked it up as a failure out of the gate. I figured that there would never be a single delivered unit. It just seemed too impossible. The price was too low for a machine with that many large machined aluminum pieces. It had real linear guides. It had a real spindle and housed a beagle bone black running linuxCNC. It just couldn’t be that cheap. Ends up, I’m quite happy to be wrong. Pocket NC is doing well, delivering their first units, and taking new orders.
It’s easy to get jaded with the Kickstarter and IndieGoGo scams that are out there. Or even the disappointing behavior of projects that could be legitimate. People often do failure analysis of companies, but it is also worth investigating what people did right when they are successful.