3D printing is a staple of the hacker community. From decorative items to rugged functional parts, almost anything you can think of, can be printed. [anurag.id] shows us some classic 3D printing hacks by converting his keyboard into a compact workstation.
Like any hacker project, the initial idea is small: he decides the knob on his mechanical keyboard is boring, so he designs some alternatives. First, one “retro style” knob. Then, like any good project, the scope creep begins. He makes another knob, and another… by the end he has 6 different designs! But don’t worry, the scope can get even bigger. He decides his ipad needs a good stand on his desk–and what better place to put it than on the keyboard? Now it’s starting to look like a real little workstation. Finally, as a finishing touch, he adds some magnetically-attached wrist rests for a compact, ergonomic workstation.
Keeping your filament safely away from moisture exposure is one of the most crucial aspects of getting a good 3D print, with equipment like a filament dryer a standard piece of equipment to help drive accumulated moisture out of filament prior to printing or storage. Generally such filament dryers use hot air to accomplish this task over the course of a few hours, but this is not very efficient for a number of reasons. Increasing the vaporization rate of water without significantly more power use should namely be quite straightforward.
The key here is the vapor pressure of a liquid, specifically the point at which it begins to transition between its liquid and gaseous phases, also known as the boiling point. This point is defined by both temperature and atmospheric pressure, with either factor being adjustable. In a pressure cooker this principle is for example used to increase the boiling temperature of water, while for our drying purposes we can instead reduce the pressure in order to lower the boiling point.
Although a lower pressure is naturally more effective, we can investigate the best balance between convenience and effectiveness.
We haven’t seen an instrument panel quite like [bluesyann]’s, which was made by curing UV resin directly onto plywood with the help of a 3D printer and a bit of software work. The result is faintly-raised linework that also makes hand drilling holes both cleaner and more accurate.
The process begins by designing the 2D layout in Inkscape, which has the advantage of letting one work in 1:1 dimensions. A 10 mm diameter circle will print as 10 mm; a nice advantage when designing for physical components. After making the layout one uses OpenSCAD to import the .svg and turn it into a 3D model that’s 0.5 mm tall. That 3D model gets loaded into the resin printer, and the goal is to put it directly onto a sheet of plywood.
A little donut shape makes a drill centering feature, and the surrounding ring keeps the edges of the hole clean.
To do that, [bluesyann] sticks the plywood directly onto the 3D printer’s build platform with double-sided tape. With the plywood taking the place of the usual build surface, the printer can cure resin directly onto its surface. Cleanup still involves washing uncured resin off the board, but it’s nothing a soak in isopropyl alcohol and an old toothbrush can’t take care of.
[bluesyann] has a few tips for getting the best results, and one of our favorites is a way to make drilling holes easier and cleaner. Marking the center of a drill hit with a small donut-shaped feature makes a fantastic centering guide, making hand drilling much more accurate. And adding a thick ring around the drill hole ensures clean edges with no stray wood fibers, so no post-drilling cleanup required. Don’t want the ring to stick around after drilling? Just peel it off. There’s a load of other tips too, so be sure to check it out.
Usually, when we see non-planar 3D printers, they’re rather rudimentary prototypes, intended more as development frames than as workhorse machines. [multipoleguy]’s Archer five-axis printer, on the other hand, breaks this trend with automatic four-hotend toolchanging, a CoreXY motion system, and print results as good-looking as any Voron’s.
The print bed rests on three ball joints, two on one side and one in the center of the opposite side. Each joint can be raised and lowered on an independent rail, which allows the bed to be tilted on two axes. The dimensions of the extruders’ motion system limit how much the bed can be angled when the extruder is close to the bed, but it can reach sharp angles further out.
The biggest difficulty with non-planar printing is developing a slicer; [multipoleguy] is working on a slicer (MaxiSlicer), but it’s still in development. It looks as though it’s already working rather well, to the point that [multipoleguy] has been optimizing purge settings for tool changes. It seems that when a toolhead is docked, the temperature inside the melt chamber rises above the normal temperature in use, which causes stringing. To compensate for this, the firmware runs a more extensive purge when a hotend’s been sitting for a longer time. The results speak for themselves: a full three-color double helix, involving 830 tool changes, could be printed with as little as six grams of purge waste.
Embedding fasteners or other hardware into 3D prints is a useful technique, but it can bring challenges when applied to large or non-flat objects. The solution? Use a gap-cap.
The gap-cap technique is essentially a 3D printed lid. One pauses a print, inserts hardware, then covers it with a lid before resuming the print. The lid — or gap-cap — does three things. It seals in the part, it fills in empty space left above the component, and it provides a nice flat surface for subsequent layers which makes the whole process much cleaner and more reliable.
This whole technique is a bit reminiscent of the idea of manual supports, except that the inserted piece is intended to be sealed into the print along with the embedded hardware under it.
If you have never inserted anything larger than a nut or small magnet into a 3D print, you may wonder why one needs to bother with a gap-cap at all. The short version is that what works for printing over small bits doesn’t reliably carry over to big, odd-shaped bits.
For one thing, filament generally doesn’t like to stick to embedded hardware. As the size of the inserted object increases, especially if it isn’t flat, it increasingly complicates the printer’s ability to seal it in cleanly. Because most nuts are small, even if the printer gets a little messy it probably doesn’t matter much. But what works for small nuts won’t work for something like an LED strip mounted on its side, as shown here.
Cross-section of a print with an embedded LED strip. The print pauses (A), LED strip is inserted and capped with a gap-cap (B, C), then printing resumes and completes (D).
In cases like these a gap-cap is ideal. By pre-printing a form-fitting cap that covers the inserted hardware, one provides a smooth and flat surface that both seals the component in snugly while providing an ideal surface upon which to resume printing.
If needed, a bit of glue can help ensure a gap-cap doesn’t shift and cause trouble when printing resumes, but we can’t help but recall the pause-and-attach technique of embedding printed elements with the help of a LEGO-like connection. Perhaps a gap-cap designed in such a way would avoid needing any kind of adhesive at all.
The concept is simple. [Shake the Future] uses silicon carbide crucibles, which can heat up by absorbing microwave energy. Put one in an insulated container, dump some metal in, and throw it in a microwave, and soon enough you have a pot of molten metal you can use to cast stuff.
Let’s say you want to make an adjustable wrench, which is how [Shake the Future] demonstrates this technique. The first step is to print the wrench parts in plastic, such as PLA. These parts are then packed into fine sand to create casting molds. The PLA is burned out of the mold, leaving a negative imprint of the geometry. Molten cast iron can then be poured into the mold to create the part in solid metal.
It’s a messy technique that requires a lot of manual labor, but it does work quite well. There are some tricks to learn, though, particularly when it comes to successfully casting parts with holes or fine geometric features.
And before you think that you’re going to put the hardware store out of business, it should also be noted that it failed on first encounter with a real-world nut. The thinnest part by the screw just wasn’t strong enough.
Although usually nylon (generally PA6) filament is pretty cheap, there are some more exotic variants out there, such as the PA12-based Lyten 3D graphene filament that comes in at a cool $150 for a 1 kg spool. Worse for [Dr. Igor Gaspar] here was that the company doesn’t ship to the EU, and didn’t respond to emails about obtaining a sample for testing. Fortunately he got a spool via a different route, so that he could test whether this is the strongest nylon filament or not.
The full name for this filament is PA1205, though it’s not certain what the ’05’ part stands for. PA12 is a less moisture-sensitive version of PA6, however. Among the manufacturer’s claims are that it’s the strongest nylon filament, as well as very lightweight and heat-resistant. Interestingly the datasheet recommends printing with an 0.6 mm nozzle, which is the only major deviation from typical nylon FDM filaments. Of course, printing with an 0.4 mm nozzle had to be tried.
With a standard PA-CF preset in Bambu Lab’s slicer the printing of test parts worked without issues, which was promising. With load testing the filament made a good showing compared to average PA filaments, though as with most fiber reinforced filaments it’s more brittle than the pure material. Compared to PA-CF this PA1205 was much less brittle than PA-CF, however. Overall it’s not a bad filament, but for the asking price it’s a tough ask.
