Gradient Infill Puts More Plastic Where You Want It

January 20, 2020 by Al Williams 13 Comments

It is always tricky setting the infill for a 3D printed part. High infill parts are strong but take longer to print, while low infill prints take less time, but are weaker internally and in danger of surface layer droop between the infill pattern. [Stephan] has a better answer: gradient infill. You can see a video below and find his Python code on GitHub.

The idea is simple enough. In most cases, parts under stress see higher stress near the surface. Putting more material there will make the part stronger than adding plastic in places where the stress is lower. [Stephan] has done finite element analysis to determine an optimal infill pattern before, but this is somewhat difficult to do. Since the majority of parts can follow the more at the edges and less at the center rule, gradient infill makes sense except for a few special cases.

Continue reading “Gradient Infill Puts More Plastic Where You Want It” →

Play That Funky 3D Printer…

January 19, 2020 by Al Williams 16 Comments

Human brains are wired for music. Scientists think the oldest musical instruments were flutes that date back somewhere between 67,000 and 37,000 years ago. We assume though that people were banging on wood or their thighs, or knocking two rocks together long before that. Almost anything can be a musical instrument. A case in point: [elifer5000] walked into a room containing a lot of running 3D printers, and thought it seemed musical. Next thing you know, he harnessed 3D printers as a MIDI instrument.

At a hackathon, he found some software that converts a MIDI file to GCode. The only problem is a common printer has three axes and, therefore, can only produce (at most) three notes at once. The obvious answer to this problem is to use more printers, and that’s what he did, as you can see below.

Continue reading “Play That Funky 3D Printer…” →

3D Printable Stick Shift For Your Racing Simulator

January 8, 2020 by Danie Conradie 22 Comments

If you don’t get enough driving in your real life, you can top it off with some virtual driving and even build yourself a cockpit. To this end [Noctiluxx] created a very nice 3D printable stick shifter you can build yourself.

The design is adapted for 3D printing from an older aluminium version by [Willynovi] over on the X-Simulator forums. Every version uses an off-the-shelf ball joint for the main pivot, below which is a guide plate with the desired shift pattern. Each position has a microswitch, which can be connected to a USB encoder from eBay which acts as a HID. The position is held in the Y-axis position by a clever spring-loaded cam mechanism above the ball joint, while the X-position is held by the bottom guide plate. The gear knob can be either 3D printed or the real deal of your choice.

This design is the perfect example of the power of the internet and open source. The original aluminium design is almost a decade old, but has been built and modified by a number of people over the years to get us to the easy to build version we see today. [amstudio] created an excellent video tutorial on how to built your own, see it after the break.

For more awesome cockpits check out this one to fly an actual (FPV) aircraft, and this dazzling array of 3D printable components for your own Garmin G1000 avionics glass cockpit. Continue reading “3D Printable Stick Shift For Your Racing Simulator” →

3D Pens Can Make Ugly Drone Parts That Almost Work

January 5, 2020 by Donald Papp 23 Comments

Small hobby aircraft and light plastic parts go hand in hand, and a 3D printing pen makes lightweight plastic things without the overhead of CAD work and running a 3D printer. So could a 3D pen create useful plastic bits for small quadcopters? [Michael Niggel] decided to find out by building his drone parts with a 3D pen loaded with ABS plastic. He mostly discovered that the created objects could politely be said to look like they were sketched by a toddler, but that’s not all he learned.

He found that in general creating an object was harder than the marketing materials implied. As soon as the filament exits the pen’s nozzle, the thin little molten line of plastic cools rapidly and does two things: it has a tendency to curl, and loses its desire to stick to things. [Michael] found the whole affair worked much less like ‘drawing in thin air’ and rather more like piping frosting, or caulking.

An almost functional micro quad frame. The arms aren’t rigid enough to hold the motors vertical when under power.

Nevertheless, [Michael] sought to discover whether a 3D pen could be used to make quick and dirty parts of any use. He created two antenna brackets and one micro quad frame. All three are chaotic messes, but one antenna bracket was perfectly serviceable. The 3D pen was indeed able to create a strangely-shaped part that would have been a nightmare to CAD up. The other antenna part worked, but didn’t do anything a zip tie wouldn’t have done better. The rapid cooling of the plastic from the 3D pen has an advantage: extrusions don’t “droop” like a glob of hot glue does before it hardens.

By now, [Michael] agreed that the best way to create a plastic part of any complexity whatsoever seemed to be to draw sections flat, build them up in layers, then use the pen to weld the pieces together and add bulk. The micro quad frame he made in this way doesn’t look any nicer than the other attempts, but it did hold the parts correctly. Sadly, it would not fly. Once the motors powered up, the arms would twist and the flight controller was unable to compensate for motors that wouldn’t stay straight. This could probably be overcome, but while the end result was dirty it certainly wasn’t quick. The 3D pen’s niche seems restricted to simple, unstressed parts that aren’t permitted to gaze up themselves in a mirror.

If you have a 3D pen, we’d like to remind you of this mini spool design whose parts are welded together with the pen itself. For bigger jobs, a high-temperature hot glue gun can be used to dispense PLA instead.

Unique 3D Printer Turned CNC Engraver

January 3, 2020 by Tom Nardi 4 Comments

As we’ve said in the past, one of the most exciting things about the proliferation of low-cost desktop 3D printers (beyond all the little boats we get to see on Reddit), is the fact that their motion control systems are ripe for repurposing. Outfitting a cheap 3D printer with a drag knife, pen holder, or even a solid-state laser module, are all very common ways of squeezing even more functionality out of these machines.

But thanks to the somewhat unusual nature of his printer, [Hammad Nasir] was able to take this concept a bit farther. Being considerably more rigid than the $99 acrylic-framed box of bolts we’ve become accustomed to, he was able to fit it with a basic spindle and use it for CNC engraving. He won’t be milling any steel on this rig, but judging by the pictures on the Hackaday.io page for the project, it does a respectable job cutting designs into plastic at least.

The IdeaWerk 3D printer that [Hammad] used for this project is phenomenally overbuilt. We don’t know whether the designers simply wanted to make it look futuristic and high-tech (admittedly, it does look like it could double as a movie prop) or they thought there was a chance it might get thrown down the stairs occasionally. In either event, it’s built like an absolute tank.

While the frame on lesser printers would likely flex as soon as the bit started moving across the workpiece, this thing isn’t going anywhere. Of course this machine is presumably still running on the standard GT2 belt and NEMA 17 arrangement that has been used in desktop 3D printers since the first wooden machines clattered to life. So while the frame might be ready to take some punishment, the drive system could respectfully disagree once the pressure is on.

Modification was simplified by the fact that the hotend and extruder assembly on the IdeaWerk is mounted to the X axis with just a single bolt. This makes it exceptionally easy to design alternate tool mounts, though arguably the 3D printed motor holder [Hammad] is using here is the weak link in the entire system; if it’s going to flex anywhere, it’s going to be there.

If you’re more photonically inclined, you might be interested in this similarly straightforward project that sees a 2.5 W laser module get bolted onto an entry level 3D printer.

A Wireless Method For Pressing Tofu

January 2, 2020 by Sharon Lin 47 Comments

Tofu is a fairly common food in East and Southeast Asian cuisines, but it has also been making its way around vegetarian circles as a meat substitute. While it may be a more environmentally friendly source of protein than meat, it does have the unfortunate side effect of being fairly tedious to cook. To reach the right consistency, tofu requires hours of pressing to drain excess water, which tends to be tedious for most amateur cooks.

A team of students at HackMIT developed a contraption that incrementally presses tofu for you, using signals sent over WiFi to initialize the device. Several 3D-printed components extend an existing food container, along with a stepper motor, motor shield, Adafruit Feather HUZZAH, and a screen.

The motor steps at a rate of 30rpm once a signal is sent from a mobile application, causing four connected threaded rods to begin rotating. The tofu tray travels upwards to press against its lid, draining out excess water. A central gear box containers complementary cutouts that allow the tofu platform to travel vertically when shafts are rotated, pushed by nuts below the platform. The students also included a screen indicating time remaining, as well as a notification sent to the user once the tofu is finished being pressed.

It’s certainly a useful solution that will hopefully increase the popularity of tofu-based recipes!

Ask Hackaday: How Do You Keep The 3D Printer From Becoming EWaste

January 2, 2020 by Jenny List 93 Comments

One thing we sometimes forget in our community is that many of the tecniques and machines that we take for granted are still something close to black magic for many outsiders. Here’s a tip: leave a 3D printer running next time you take a group of visitors round a hackerspace, and watch their reaction as a Benchy slowly emerges from the moving extruder. To us it’s part of the scenery, but to them it’s impossibly futuristic and their minds are blown.

Just because something says it's a Prusa i3, doesn't mean it is a Prusa i3. — Just because something *says* it’s a Prusa i3, doesn’t mean it is a Prusa i3.

Nearly 15 years after the dawn of the RepRap project we have seen a huge advancement in the capabilities of affordable 3D printers, and now a relatively low three-figure sum will secure a machine from China that will churn out prints whose quality would amaze those early builders. We’ve reached the point in our community at which many people are on their third or fourth printer, and this has brought with it an unexpected side-effect. Where once a hackerspace might have had a single highly prized 3D printer, now it’s not unusual to find a pile of surplus older printers on a shelf. My hackerspaces both have several, and it’s a sight I’ve frequently seen on my travels around others. Perhaps it’s a sign of a technology maturing when it becomes ewaste, and thus it seems affordable 3D printing has matured. Continue reading “Ask Hackaday: How Do You Keep The 3D Printer From Becoming EWaste” →