[Stephan Henrich] is probably going to set off a wave of bigfoot sightings if his new shoe, the Cryptide sneaker takes off. The shoe is completely 3D printed in flexible TPE using a laser sintering printer from Sintratec. The shoe takes a name from cryptozoology and, in fact, would leave a puzzling footprint due to its articulated toes and scaly-looking sole.
Judging from the look of the sole, it should be pretty cushy and we presume if you were 3D printing these, you’d scan or precisely measure the intended foot for a perfect fit. You can see a video about the shoe below.
Continue reading “3D Printed Shoes Make Bigfoot Tracks”
You might not think to use the word “rigid” to describe most 3D-printer filaments, but most plastic filaments are actually pretty stiff over a short length, stiff enough to be pushed into an extruder. Try the same thing with a softer plastic like TPE, though, and you might find yourself looking at this modified Bowden drive for elastomeric filaments.
The idea behind the Bowden drive favored by some 3D-printer designers is simple: clamp the filament between a motor-driven wheel and an idler to push it up a pipe into the hot end of the extruder. But with TPE and similar elastomeric filaments, [Tech2C] found that the Bowden drive on his Hypercube printer was causing jams and under-extrusion artifacts in finished prints. A careful analysis of the stock drive showed a few weaknesses, such as how much of the filament is not supported on the output side of the wheel. [Tech2C] reworked the drive to close that gap and also to move the output tube opening closer to the drive. The stock drive wheel was also replaced with a smaller diameter wheel with more aggressive knurling. Bolted to the stepper, the new drive gave remarkably improved results – a TPE vase was almost flawless with the new drive, while the old drive had blobs and artifacts galore. And a retraction test print showed no stringing at all with PLA, meaning the new drive isn’t just good for the soft stuff.
All in all, a great upgrade for this versatile and hackable little printer. We’ve seen the Hypercube before, of course – this bed height probe using SMD resistors as strain gauges connects to the other end of the Bowden drive.
Continue reading “A Better Bowden Drive For Floppy Filaments”
Zizzy is a personal robot designed to help those with limited mobility. Rather than being assisted by a nightmare creature, Zizzy would offer a more appealing and friendly option.
The coolest part about Zizzy is the 3D printable pneumatic artificial muscles. Project creator, [Michael Roybal] said it took over a year of development to arrive at the design.
The muscles are hollow bellows printed out of Ninjaflex with carefully calibrated settings. A lot of work must have gone into the design to make sure that they were printable. After printing the muscles are painted with a mixture of fabric glue and MEK solvent. If all is done correctly the bellows should be able to hold 20 PSI without any problem.
This results in a robot with very smooth and precise movement. It has none of the gear noise and can also give when it collides with a user, a feature typically found only in very expensive motor systems. If [Michael] can find a quiet compressor system the robot will be nearly silent.