Ender 3 Meets MIG Welder To Make A Metal Benchy — Kind Of

November 23, 2021 by Dan Maloney 20 Comments

When you can buy a 3D printer at Aldi, you pretty much know that 3D printing has been reduced to practice. At least for the plastic version of 3D printing; metal printing is another thing entirely. It’s easy to squeeze out a little molten plastic in a controlled fashion, but things get a little more — energetic — when you try to do the same with metal.

At least that’s what [Lucas] has been experiencing with his attempts to build a metal 3D printer over on his Cranktown City YouTube channel. Granted, he set himself up for a challenge from the get-go by seeking to stick a MIG welder onto an Ender 3, a platform that in no way was ready for the abuse it was about to endure. Part 1 of the video series below shows the first attempt, which ended badly for both the printer and for the prints.

But that first prototype, melted parts notwithstanding, gave [Lucas] enough to go on for the improvements of version 2, including a better build plate, heat shielding for the printer’s tender bits, and a legit MIG welder wire feeder. [Lucas] also built current control in, with a clever non-destructive interface to the welder controls. These improvements were enough to attempt a Benchy print, which started out pretty decent but got a bit droopy toward the end.

As imperfect as it is, the Benchy is a vast improvement over the formless blobs from version 1, and the printer holds quite a bit of promise for the future. One thing you can’t accuse [Lucas] of is giving up on a project too easily; after all, he built a laser cutter from scratch, including the laser tube.

Continue reading “Ender 3 Meets MIG Welder To Make A Metal Benchy — Kind Of” →

DIY High Flow 3D Printing Nozzle

November 23, 2021 by Al Williams 50 Comments

Sometimes advances happen when someone realizes that a common sense approach isn’t the optimal one. Take radio. Success in radio requires bigger antennas and more power, right? But cell phones exist because someone realized you could cram more people on a frequency if you use less power and smaller antennas to limit the range of each base station. With FDM 3D printing, smaller nozzles were all the rage for a while because they offer the possibility of finer detail. However, these days if you want fine detail you should be using resin-based printers and larger nozzles offer faster print times and stronger parts. The Volcano hotend started this trend but there are other options now. [Stefan] over at CNC Kitchen decided to make his own high flow nozzle and he claims it is better than other options.

Don’t get too carried away with the DIY part. As you can see in the video below, he starts with a standard nozzle, so it is really a nozzle conversion or hack. The problem with high flow isn’t the hole in the nozzle. It is melting the plastic fast enough. The faster the plastic moves through the nozzle, the less time there is for it to melt.

Continue reading “DIY High Flow 3D Printing Nozzle” →

A PDP 11 By Any Other Name: Heathkit H11 Teardown And Repair

November 22, 2021 by Al Williams 31 Comments

[Lee Adamson] is no stranger to classic computers. He recently picked up a Heathkit H11A which, as you might remember, is actually a PDP-11 from DEC. Well, technically, it is an LSI-11 but still. Like a proper LSI-11, the computer uses the DEC QBus. Unlike a lot of computers of its day, the H11 didn’t have a lot of switches and lights, but it did have an amazing software library for its day.

[Lee] takes us through a tour of all the different cards inside the thing. It is amazing when you think of today’s laptop motherboards that pack way more into a much smaller space. He also had to fix the power supply.

Continue reading “A PDP 11 By Any Other Name: Heathkit H11 Teardown And Repair” →

Visualizing WiFi With A Converted 3D Printer

November 22, 2021 by Dan Maloney 9 Comments

We all know we live in a soup of electromagnetic radiation, everything from AM radio broadcasts to cosmic rays. Some of it is useful, some is a nuisance, but all of it is invisible. We know it’s there, but we have no idea what the fields look like. Unless you put something like this 3D WiFi field strength visualizer to work, of course.

Granted, based as it is on the gantry of an old 3D printer, [Neumi]’s WiFi scanner has a somewhat limited work envelope. A NodeMCU ESP32 module rides where the printer’s extruder normally resides, and scans through a series of points one centimeter apart. A received signal strength indicator (RSSI) reading is taken from the NodeMCU’s WiFi at each point, and the position and RSSI data for each point are saved to a CSV file. A couple of Python programs then digest the raw data to produce both 2D and 3D scans. The 3D scans are the most revealing — you can actually see a 12.5-cm spacing of signal strength, which corresponds to the wavelength of 2.4-GHz WiFi. The video below shows the data capture process and some of the visualizations.

While it’s still pretty cool at this scale, we’d love to see this scaled up. [Neumi] has already done a large-scale 3D visualization project, using ultrasound rather than radio waves, so he’s had some experience in this area. But perhaps a cable bot or something similar would work for a room-sized experiment. A nice touch would be using an SDR dongle to collect signal strength data, too — it would allow you to look at different parts of the spectrum.

Continue reading “Visualizing WiFi With A Converted 3D Printer” →

Shop-Built Rig Measures Strength Of Wood Accurately

November 22, 2021 by Dan Maloney 7 Comments

Wood is an incredibly versatile material, but like everything else, it has its limits. Build a chair from weak wood and the worst that can happen is probably not that bad. But if you build machine tools from wood, the stakes for using the wrong wood can be a bit higher.

That’s the thinking behind the wood strength testing setup [Matthias Wandel] came up with. Previously, he had a somewhat jury-rigged test setup with a hydraulic bottle jack to apply force to the test piece and a bathroom scale to make measurements. That setup was suboptimal, so version two used a jackscrew to apply the force, but the bathroom scale still left the measurements open to interpretation. Version three, the topic of the video below, went with strain gauges and an A/D converter connected to a Raspberry Pi to automate data collection. The jackscrew was also integrated into the test setup with a stepper motor and, of course, [Matthias]’ famous wooden gears.

While the test rig is pretty simple in design, there’s a lot of subtlety to the calibration to make sure that it’s measuring the test material itself and not just compliance within the mechanism. It’s just another in a long line of data-gathering exercises that [Matthias] seems to groove on, like his recent woodshop electrical explorations.

Continue reading “Shop-Built Rig Measures Strength Of Wood Accurately” →

GBA Remote Play Upgrade Lets You Play PlayStation On The Bus

November 22, 2021 by Lewin Day 4 Comments

The Nintendo Game Boy Advance was basically the handheld gaming situation of its era, by virtue of the fact that it had no serious competitors in the market. The system was largely known for 2D games due to hardware limitations.

However, [Rodrigo Alfonso] has recently upgraded his GBA Remote Play system that lets him play PlayStation games and others on his classic Game Boy Advance. We first featured this project back in July, which uses a Raspberry Pi 3 to emulate games and pipe video data to the handheld for display, receiving button presses in return.

Since then, [Rodrigo] has given the project some upgrades, in the form of a 3D-printed case that mounts a battery-powered Pi directly to the back of the console for portable play. Additionally, overclocking the GBA allows for faster transfer rates over the handheld’s Link Port, which means more pixels of video data can be clocked in. This allows for more playable frame rates when running at 240×160, the maximum resolution of the GBA screen.

The result is a Game Boy Advance which you can use to play Crash Bandicoot on the bus just to confuse the normies. Of course, one could simply build a Raspberry Pi handheld from scratch to play emulated games. However, this route takes advantage of the GBA form factor and is pretty amusing to boot. Video after the break.

Continue reading “GBA Remote Play Upgrade Lets You Play PlayStation On The Bus” →

Simple But Stylish Numitron Clock Can Display Time, Date And Temperature

November 22, 2021 by Robin Kearey 6 Comments

While it seems like Nixie tubes get all the attention when it comes to making retro-style displays, there are plenty of other display technologies that can make a good-looking retro design. Take the Numitron tube: introduced by RCA in the early 1970s, these display tubes might look superficially similar to Nixies but work in a completely different way. The Numitron uses incandescent elements that make up seven-segment displays.

The main advantage Numitrons have over Nixes is that they don’t require a high-voltage supply, which makes them much easier to hook up to modern low-voltage electronics. [mircemk] used this to his advantage when he built a simple clock using four numitrons that can display the time, the date, and the ambient temperature.

The brains of the device are formed by an Arduino Nano coupled with a DS3231 battery-backed real-time clock module. For now, the time has to be synchronized by connecting the Arduino to a PC and reprogramming it, but [mircemk] has plans to update the design with pushbuttons to allow the user to set the time manually.

Four shift registers are all that’s needed to interface the microcontroller to the display tubes, thanks to their low-voltage operation. They do need quite a lot of current, so [mircemk] used the high-power TPIC6C595 instead of a regular 74HC595 chip. We wonder if the tubes’ high power consumption could be the reason why the temperature in his lab seems to hover around 30 °C.

A simple but stylish plastic enclosure completes the design. Since Numitron tubes are relatively low-cost and no other specialized components are needed, this could be one of the cheapest and easiest ways to make a retro display tube clock. Although we’ve seen a couple of Numitron clocks and even watches before, today’s build is a great example of how simple such a design can actually be. Continue reading “Simple But Stylish Numitron Clock Can Display Time, Date And Temperature” →