3D printers are now cheaper than ever and Monoprice is at the absolute forefront of that trend. However, some of their printers struggle with flexible filaments, which is no fun if you’ve discovered you have a taste for the material properties of Ninjaflex and its ilk. Fear not, however — the community once again has a solution, in the form of a hot end adapter for the Monoprice Mini Delta.
The Mini Delta is a fantastic low-cost entry into 3D printing but its hot end has a break in the Bowden between the extruder and nozzle. This can lead to flexible filaments not being properly guided through the hot end and a general failure to print. This adapter allows the fitting of the popular E3D V6 hot end, and is similar to modifications out there for other Monoprice printers.
Overall, 3D printing has long benefited from the efforts of the community to bring both incremental improvements and major leaps forward to the technology. We look forward to seeing more hacks on the Monoprice range!
We’ve always been fascinated at the number of ways logic gates can spring into being. Sure, we think of logic gates carrying electrons, but there are so many other mechanical means to do the same thing. Another method that sometimes has a practical use is fluidic or pneumatic logic. We guess [dAcid] has a similar interest since he’s written two posts on how to construct the gates. One post covers making them with ordinary tools. The other requires an SLA printer.
According to [dAcid], the design is effectively the same either way, but the SLA printing is more precise. Silicone is an important component, either way. Fluidic logic has applications in some mechanical systems, although digital logic has made it less important than it once was. However, it is very possible that nanotechnology systems will implement logic mechanically, so this is still an interesting technique to understand. You can see videos of how a D latch looks using both methods, below.
Dual extrusion 3D printers are not as uncommon as they used to be, but there are still a lot of single-extruder machines. [Paul Lang] wanted to refit his printer to take two MK8 extruders, and he documented his experience with a blog post that has a few good tips if you want to try it yourself.
[Paul] used Fusion 360 to design a holder for the extruders that would fit his printer. Since he had accidentally ordered a spool of pink PLA, the whole assembly is shocking pink — not subtle at all. He shares a few design tips about using PLA near the hot areas and making everything fit and level.
[Thomas Sanladerer] is at it again: testing all of the 3D-printer filaments that are fit to print (with). And this year, he’s got a new and improved testing methodology — video embedded below. And have a search for “filaween2” to see what he’s reviewed so far. There’s some sexy filaments in there.
We really love the brand-new impact strength test, where a hammer is swung on a pivot (3D printed, natch), breaks through the part under test, and swings back up to a measurable height. The difference in swing height reflects the amount of energy required to break the test piece. Sweet physics.
Here’s some interesting work shared by [Ben Kromhout] and [Lukas Lambrichts] on making flexible 3D prints, but not by using flexible filament. After seeing a project where a sheet of plywood was rendered pliable by cutting a pattern out of it – essentially turning the material into a giant kerf bend – they got interested in whether one could 3D print such a thing directly.
The original project used plywood and a laser cutter and went through many iterations before settling on a rectangular spiral pattern. The results were striking, but the details regarding why the chosen pattern was best were unclear. [Ben] and [Lukas] were interested not just in whether a 3D printer could be used to get a similar result, but also wanted to find out what factors separated success from failure when doing so.
After converting the original project’s rectangular spiral pattern into a 3D model, a quick proof-of-concept showed that three things influenced the flexibility of the end result: the scale of the pattern, the size of the open spaces, and the thickness of the print itself. Early results indicated that the size of the open spaces between the solid elements of the pattern was one of the most important factors; the larger the spacing the better the flexibility. A smaller and denser pattern also helps flexibility, but when 3D printing there is a limit to how small features can be made. If the scale of the pattern is reduced too much, open spaces tend to bridge which is counter-productive.
Kerf bending with laser-cut materials gets some clever results, and it’s interesting to see evidence that the method could cross over to 3D printing, at least in concept.
[Robin Reiter] had a powered TV stand that only rotates around 20°, because who really needs their TV to rotate fully? He wanted to turn it into a motorized turntable for shooting videos, but first he had to hack it.
After opening it up [Robin] discovered that there was a surprising amount of electronics in the base. In addition to a DC motor, there was a potentiometer attached to a gear to give feedback, but it was set up for partial rotation so it had to be yanked out.
There was also a plastic gear with teeth around just part of the interior. [Robin] took a picture of the gear and dropped it into Fusion360, using the photo as a reference image while he re-created the gear. The new piece had teeth all around the periphery. After printing it out he glued it into the old gearbox, and now he had turned his TV stand into a motorized turntable.
A key feature of many manufacturing processes is the use of fixtures and jigs to hold parts during machining and assembly operations. These must be developed before manufacturing begins and must be custom made to suit the given application. Many manufacturers outsource the development of such fixturing, even in large operations – even major automakers will often outsource development of fixtures and new process lines to outside firms. This can have major ramifications when changes need to be made, introducing costly delays. However, 3D printers can be used to rapidly iterate fixturing designs to suit new parts, greatly reducing development time. As stated in the article, Louis Vuitton uses this to great effect – the reduced time of development is incredibly useful when changing manufacturing lines every few months in the fashion industry.
Obviously there are limitations – in a factory producing large steel castings, it’s unlikely a FDM-printed fixture will be much use when it comes to the wear and tear of machining hundreds of castings a day. However, as a development tool, it can prove very useful. What’s more, jigs for light industrial work – think electronics assembly, woodworking glue-ups, or any form of delicate work by hand – need not be as robust. Lightweight, readily produced 3D printed parts may be just the ticket.
Another great benefit of 3D printing is its ability to be used for mockups. You may be designing a product that requires several aluminium parts to fit together, but alas – the parts won’t be ready for weeks. Rather than wait all that time, only to find out something doesn’t fit right, it may be advantageous to print out a plastic version of the parts. Being able to check geometry with actual parts is often very useful, and makes a great tool if you need to present your work to others. It’s much easier to communicate an idea to people if they can hold and touch what you’re talking about!
It’s something worth considering if you’re setting up any sort of small production line – perhaps you’re looking for a way to make populating a run of PCBs faster, or ease the assembly of a series of distributed sensor modules. These techniques may prove particularly useful if you consider yourself a scrappy hacker.