Self-assembling Polymers Support Silicone 3D Prints

We all know what the ultimate goal of 3D printing is: to be able to print parts for everything, including our own bodies. To achieve that potential, we need better ways to print soft materials, and that means we need better ways to support prints while they’re in progress.

That’s the focus of an academic paper looking at printing silicone within oil-based microgels. Lead author [Christopher S. O’Bryan] and team from the Soft Matter Research Lab at the University of Florida Gainesville have developed a method using self-assembling polymers soaked in mineral oil as a matrix into which silicone elastomers can be printed. The technique takes advantage of granular microgels that are “jammed” into a solid despite being up to 95% solvent. Under stress, such as that exerted by the nozzle of a 3D printer, the solid unjams into a flowing liquid, allowing the printer to extrude silicone. The microgel instantly jams back into a solid again, supporting the silicone as it cures.

[O’Bryan] et al have used the technique to print a model trachea, a small manifold, and a pump with ball valves. There are Quicktime videos of the finished manifold and pump in action. While we’ve covered flexible printing options before, this technique is a step beyond and something we’re keen to see make it into the hobby printing market.

[LonC], thanks for the tip.

Monoprice Releases Their Mini Delta Printer (On Indiegogo)

Around this time last year, Monoprice quietly unveiled a small, $200 3D printer. At the time, a fully functioning printer at this price point wasn’t unheard of. A good 3D printer at this price point was. It turned out this printer was actually fantastic and completely changed the value proposition of desktop 3D printers.

In the year since the release of the MP Select Mini printer, Monoprice has been hard at work bringing costs down, reworking designs, and creating an even less expensive printer. Now, it’s out. It’s available for pre-order on Indiegogo right now. Is this still a $150 printer? Not quite: the ‘early bird’ price is $159 with free shipping and August delivery, and a regular price of $169 plus $10 shipping with September or October delivery. There’s also a bundle for $279 that includes the printer, 2kg of filament, and a software package.

The first time we saw this tiny printer was way back in January at CES. It looked to be an extremely capable printer; the only question was if Monoprice could produce it and get it out the door. This would be a tall order; this printer comes with NEMA 17 stepper motors, a heated bed, a 32-bit controller board, and has WiFi enabled.

Here’s what we know about the capabilities of this printer. It’s a fairly standard delta printer with Bowden extruder and a heated bed. PLA and ABS is supported. The printer has auto bed leveling that measures the bed by ‘tapping’ the nozzle against the bed in about a dozen places before printing. From what we saw at CES, the hot end appears similar to the first revision of the $200 MP Select Mini — possibly opening up the door to E3D hot end installations.

Is this printer worth it? Every 3D printer released on a crowdfunding platform should come with the standard warnings, but Monoprice says this machine is in production right now. This raises the question: why release it on Indiegogo when Monoprice already has the whole ‘taking orders for products online’ thing in the bag? I suspect this crowdfunding campaign is just building a buffer; a year ago, the MP Select Mini was perpetually out of stock, and demand far outstripped supply. The same thing will happen with a 3D printer that’s even deeper into impulse buy territory.

In any event, the printer we’ve all been waiting for has been ‘released’, for varying values of ‘released’. The first units will start making their way onto desktops this summer, and we’re going to pick one up and put it through its paces. You can check out Monoprice’s video of this printer below.

Continue reading “Monoprice Releases Their Mini Delta Printer (On Indiegogo)”

3D Printing Custom LED Bar Graphs

[BikerGlen] wanted to spice up his zombie containment unit (see video below) so he designed and 3D printed some very cool looking bar graphs. Apparently, you can get curved bar graph LEDs, but only if you buy a fairly large quantity. Hand soldering discrete LEDs at the perfect angle would be frustrating, but with a 3D printed jig, it was a piece of cake.

The devices use a MAX6954 LED driver, so it needs very few parts and takes commands via SPI. The chips were not cheap, but the small size and high integration sold [Glen] on it.

Continue reading “3D Printing Custom LED Bar Graphs”

Transparent 3D Printing?

Transparent plastic is nothing new. However, 3D prints are usually opaque or–at best–translucent. [Thomas Sanladerer] wanted to print something really transparent. He noticed that Colorfabb had an article about printing transparent pieces with their HT filament. [Thomas] wanted to try doing the same thing with standard (and cheaper) PETG, which is chemically similar to the HT. Did he succeed? Watch the video below and find out.

You can get lots of clear plastic filament, but the process of printing layers makes the transparency turn cloudy, apparently mostly due to the small gaps between the layers. The idea with the HT filament is to overextrude at a high enough temperature that the layers can fuse together.

[Thomas] wanted to create some clear parts and diffusers for lamps. The diffusers print using vase mode and the lamps he creates when them look great even without clear diffusers.

His first experiments involved layer height and extrusion rates. He tried to determine what was making things better and worse and modifying his technique based on that. There were also some post-processing steps he tried.

If you want to see what the Colorfabb HT parts made by someone other than Colorfabb look like, check out the second video below from [3D Printing Professor]. The prints he is making don’t look very clear until he does some post processing. Even after the post processing, it isn’t going to fool anyone into thinking it is glass-clear. However, the parts that Colorfabb shows on their blog post about the material do look amazing. Between the overextrusion used to prevent gaps and the post processing steps, [3D Printing Professor] warns that it won’t be easy to get parts with precise dimensions using this technique.

If you have a big budget, you could try printing with actual glass. There seem to be several ways to do that.

Another Printer With An Infinite Build Volume

Very rarely do we see a 3D printer that is more than just a refinement of what’s currently standard practice. [Prusa]’s single-hotend, four-color printer makes the list, but that came out a while ago. The novel 32-bit controller board found in last year’s $200 Monoprice printer has the potential to change a cottage industry. Save those two exceptions, innovation in 3D printing really isn’t seeing the same gains we saw in 2010 or 2011.

A company out of the Netherlands, Blackbelt 3D, is bringing out the most innovative 3D printer we’ve seen since last March. It’s an infinite volume 3D printer that’s built for autonomous production. This printer can produce row after row of 3D printed parts, or it can print an object longer than the build plate. If you have enough time, filament, and electricity, there’s no reason you couldn’t print a plastic beam hundreds of meters long.

The specs on this printer are about what you would expect from a large machine meant for industry or prototyping, as opposed to a machine designed to print out tugboats and fidget spinners. The Blackbelt uses interchangeable print heads for the hotend with 0.4, 0.6 or 0.8 mm nozzles. The filament feed is a Bowden with the extruder hidden under the control panel. The frame is explicitly Bosch extrusion, and the machine’s build volume is 340 mm by 340 mm by whatever. Retail price (on Kickstarter) comes in at €9,500, but for an extra €3,000 you can also get a neat stand with casters on the bottom. Of course, with an infinite build volume, you could also print a stand. Continue reading “Another Printer With An Infinite Build Volume”

3D-Printed Tiger Lopes with the Help of a Motor

[Greg Zumwalt], master of 3D-printed mechanisms, has published his Saber 2 project as well as an assembly Instructable telling you how to put it together.

Saber 2 is a 3D-printed gear-and-cam saber-toothed tiger that can be motorized to show an excellent loping movement. It’s 14” long and 10” tall and consists of 108 components of which 34 are unique parts, and it all moves with the help of a 6 VDC 60 RPM gearmotor. With threaded PLA rods to keep it all together, and tapped holes to secure the rods, one imagines the printer would have to be pretty finely tuned and leveled for the parts to move as elegantly as you see in the video.

Hackaday readers might recall [Greg]’s 3D-printed projects such as his balloon-powered engine as well as his toy car also powered by balloons.

Continue reading “3D-Printed Tiger Lopes with the Help of a Motor”

Monoprice Select Mini Gets Smooth

We’ve had a love affair with the Monoprice Select Mini since it came out. The cheap printer has its flaws, though. One of them is that the controller is a bit opaque. On the one hand, it is impressive that it is a 32-bit board with an LCD. On the other hand, we have no way to modify it easily other than loading the ready-built binaries. Want to add bed leveling? Multiple fans? A second extruder and mixing head? Good luck, since the board doesn’t support any of those things. [mfink70] decided the controller had to go, so he upgraded his Mini with a Smoothie board.

On the plus side, the Smoothie board is also a 32-bit board with plenty of power and expansion capability. On the downside, it costs about half as much as the printer does. Just replacing the board was only part of the battle. [mfink70] had to worry about the steppers, the end stops, and a few other odds and ends.

Continue reading “Monoprice Select Mini Gets Smooth”