A few machines have truly changed the world, such as the wheel, steam engines, or the printing press. Maybe 3D printers will be on that list one day too. But for today, you can use your 3D printer to produce a working printing press by following plans from [Ian Mackay]. The machine, Hi-Bred, allows you to place printed blocks in a chase — that’s the technical term — run a brayer laden with ink over the type blocks and hand press a piece of paper with the platen.
The idea is more or less like a giant rubber stamp. As [Ian] points out, one way to think about it is that white pixels are 0mm high and black pixels are 3mm high. He suggests looking at old woodcuts for inspiration.
The microscope build actually took two forms. One, a regular digital microscope any of us may be familiar with, using a C-mount microscope lens fitted to a Raspberry Pi HQ camera. The other, a polarimetric microscope, using an Allied Vision Mako G-508B POL polarimetric camera instead, with the same microscope lens. The polarimetric camera takes stunning false-color images, where the color values correspond to the polarization of the light bouncing off an object. It’s incredibly specialized hardware with a matching price tag, but [E/S Pronk] hopes to build a cheaper DIY version down the line, too.
3D printers make excellent microscopes, as they’re designed to make small precise movements and are easily controlled via G-Code. We’ve seen them used for other delicate purposes too – such as this one modified to become a soldering robot. Video after the break.
Everyone wants to print using metal. It is possible, but the machines to do the work are usually quite expensive. So it caught our eye when MakerBot announced a printer — armed with an experimental extruder — that can print stainless steel parts. Then we read a bit more and realized that it can only sort of do the job. It needs a lot of help. And with some reasonable, if not trivial, modifications, your printer can probably print metal as well.
The key part of the system is BASF Ultrafuse 316L Stainless Steel filament, something that’s been around for a few years. This is a polymer with metal incorporated into it. This explains the special extruder, since metal-bearing filament is hell on typical 3D printer nozzles. However, what comes out isn’t really steel — not yet. For that, you have to send the part to a post-processing facility where it is baked at 1380 °C in a pure hydrogen atmosphere using special equipment. This debinding and sintering produces a part that the company claims can be up to 96% pure metal.
Infinite-bed 3D printers have long been an object of desire in our community, but it has taken a long time for the promise to catch up with the reality in terms of relatively affordable models that live up to expectations. They’re still a little expensive compared to their fixed-bed cousins though, so if you hanker for a Creality CR30 but only have the cash for an Ender 3, [Michael Sgroi] may have the project for you. He’s created the EnderLoop, a set of parts to perform the conversion from a stock Ender 3 to a fully-functional belt printer.
It takes the Ender 3 gantry and tilts it sideways on a pair of 3D printed supports, and replaces the stock Y azis with a belt on rollers driven by a larger motor through a timing belt drive. He has a variety of suggestions for sourcing a belt, and in his case he’s chosen one from PowerBelt3D. As well as the GitHub repository already linked, it can also be found on Thingiverse.
It’s clear that hacking apart a reliable printer in this way is not for the faint-hearted, and that a cautious hacker might prefer to wait a while for a cheaper off-the-shelf model. But we can see that the reliability of the Ender 3 will mean that its parts are still of decent quality in the new configuration, and that it looks as though the base printer can be reassembled should a belt-based build be a failure. Infinite bed printers will inevitably have a major presence in our community, and it is designs such as this one which will lead the way as they evolve into reliable machines.
There’s an old joke about the physics student tasked with finding the height of a building using a barometer. She dropped the barometer from the roof and timed how long it took to hit the ground. Maybe that was a similar inspiration to [Moe_fpv_team’s] response to the challenge: use a 3D printer to create a PC board. The answer in that case? Print a CNC mill.
[Moe] had some leftover 3D printer parts. A $40 ER11 spindle gets control from the 3D printer software as a fan. The X, Y, and Z axis is pretty standard. The machine can’t mill metal, but it does handy on plywood and fiber board and should be sufficient to mill out a PCB from some copper clad board.
Most 3D printers use leadscrews for at least one axis. These are simple devices that are essentially a steel screw thread and a brass nut that travels on it. However, for maximum precision, you’d like to use a ball screw. These are usually very expensive but have many advantages over a leadscrew. [MirageC] found cheaper ball screws but, since they were inexpensive, they had certain limitations. He designed a simple device that improves the performance of these cheap ball screws.
Superficially, a ball screw looks like a leadscrew with an odd-looking thread. However, the nut is very different. Inside the nut are ball bearings that fit in the grooves and allows the nut to spin around with much less friction. A special path collects the ball bearings and recirculates them to the other side of the nut. In general, ball screws are very durable, can handle higher loads and higher speeds, and require less maintenance. Unlike leadscrews, they are more expensive and are usually quite rigid. They are also a bit noisier, though.
Ball screws are rated C0 to C10 precision where C10 is the least accurate and the price goes up — way up — with accuracy. [MirageC] shows how cheaper ball screws can be rolled instead of precision ground. These screws are cheaper and harder, but exhibit more runout than a precision screw.
This runout caused wobble during 3D printing that was immediately obvious on the prints. Using a machinist’s dial gauge, [MirageC] found the screws were not straight at all and that even a relatively poor C7 ball screw would be more precise.
The solution? A clever arrangement of 3D printed parts. ball bearings, and magnets. The device allows the nut to move laterally without transmitting it to the print bed. It is a clever design and seems to work well.
Controlling most desktop 3D printers is as easy as sending them G-code commands over a serial connection. As you might expect, it takes a relatively quick machine to fire off the commands fast enough for a good-quality print. But what if you weren’t so picky? If speed isn’t a concern, what’s the practical limit on the type of computer you could use?
In an effort to answer that question, [Max Piantoni] set out to control his Ender 3 printer with an authentic Apple IIc. Things were made a bit easier by the fact that he really only wanted to use the printer as a 2D plotter, so he could ignore the third dimension in his code. All he needed to do was come up with a BASIC program that let him create some simple geometric artwork on the Apple and convert it into commands that could be sent out over the computer’s serial port.
Unity controlling the Ender 3
Unfortunately, [Max] ran into something of a language barrier. While the Apple had no problem generating G-code the Ender’s controller would understand, both devices couldn’t agree on a data rate that worked for both of them. The 3D printer likes to zip along at 115,200 baud, while the Apple was plodding ahead at 300. Clearly, something would have to stand in as an interpreter.
The solution [Max] came up with certainly wouldn’t be our first choice, but there’s something to be said for working with what you know. He quickly whipped up a program in Unity on his Macbook that would accept incoming commands from the Apple II at 300 baud, build up a healthy buffer, and then send them off to the Ender 3. As you can see in the video after the break, this Mac-in-the-middle approach got these unlikely friends talking at last.
We’re reminded of a project from a few years back that aimed to build a fully functional 3D printer with 1980s technology. It was to be controlled by a Commodore PET from the 1980s, which also struggled to communicate quickly enough with the printer’s electronics. Bringing a modern laptop into the mix is probably cheating a bit, but at least it shows the concept is sound.
