3D-Printed COVID Stuff That’s Not Face Shields Or Ventilators

The coolest stories from the hacker community this year are the rapid manufacturing efforts that have gone on in response to COVID-19. But [Mark Rehorst], frequently featured on these pages for his clever takes on 3D printing, shared a couple of really useful prints that are out of the ordinary for what we’ve been seeing: bias tape folders and ear savers.

Initial bias tape folding jig design by ongaroo

Tailors around the world have threaded the needle on grass-roots face mask production. One of the more labor intensive parts of sewing a face mask is the fastening mechanism. With elastic straps, the size of the loops needs to be just right, but when you run out of elastic you need to sew straps. Bias tape is a popular material for that, but it’s finicky to fold and hold it for sewing.

[Mark] heard of the need and grabbed a bias tape folder design from Thingiverse. These work kind of like a zipper, pulling in the unfolded tape on one side and feeding it out the other, folded nicely for the needle and thread to take over. But of course he did one better, refining the original design to use less plastic to get more parts, faster, with less material use — win, win, win.

Speaking of those mask straps, it turns out the backs of your ears don’t like being rubbed raw for back-to-back-to-back 12-hour shifts at the hospital. We’ve seen health workers, themselves skilled hackers, recommend sewing buttons onto a headband to hold the mask straps.

But the 3D-printing world has an “earsaver” that provides a series of hooks on a plastic band that loops behind your head. Once again, [Mark] iterated on the standard design, finding ways to reduce material use while also fitting more units onto a single printer bed.

These functional prints are glamorous in their own ways. We love seeing hard-working 3D-printed items, but we love it even more when we see them getting better and better with each new version. The back story and the design files for the improved versions are available on his project writeup. Go [Mark]!

Threading 3D Printed Parts: How To Use Heat-Set Inserts

We can make our 3D-printed parts even more capable when we start mixing them with some essential “mechanical vitamins.” By combining prints with screws, nuts, fasteners, and pins, we get a rich ecosystem for mechanism-making with capabilities beyond what we could simply print alone.

Today I’d like to share some tips on one of my favorite functional 3D-printing techniques: adding heat-set inserts. As someone who’s been installing them into plastic parts for years manually, I think many guides overlook some process details crucial to getting consistent results.

Make no mistake; there are a handful of insert guides already out there [1, 2]. (In fact, I encourage you to look there first for a good jump-start.) Over the years though, I’ve added my own finishing move (nothing exotic or difficult) which I call the Plate-Press Technique that gives me a major boost in consistency.

Join me below as I fill in the knowledge gaps (and some literal ones too) to send you back to the lab equipped with a technique that will give you perfectly-seated inserts every time.

Continue reading “Threading 3D Printed Parts: How To Use Heat-Set Inserts”

A 3D Printed Car Jack? No, Seriously!

Ah nuts, I lost my car jack again. What will I do? Well, why not 3D print a new one?

Uploaded to Thingiverse earlier this week, this design allows you to 3D print a fully functional car jack — provided your build platform is large enough. It’s actually a bit of a promo for the Cheetah 2, a massive┬ámodular 3D printer by [Hans Fouche]. Earlier this year we shared his 3D printed lawn mower; which spoiler, also works.

The neat thing about the Cheetah 2 is that it doesn’t use filament. It actually processes plastic pellets right inside the hot end, allowing for much cheaper material — typically dollars on the kilogram, as opposed to the $30+/kg we’re all used to being gouged on. Of course, you could also make your own filament. Continue reading “A 3D Printed Car Jack? No, Seriously!”