This week on Maker Update: CNC Routing on the cheap, a wiggly gearbox, creepy robots, Jitterbugs, Vintage safety glasses, and what to do when someone steals your design.

++Show Notes [Maker Update Ep. 232]++

-=Project of the Week=-

$50 diy cnc router by DAZ Projects
https://www.youtube.com/watch?v=xfFhh5kzQms

-=News=-

Shapeoko 4 Announced
https://www.youtube.com/watch?v=w-8n6hmgS9w

-=More Projects=-

3d printed harmonic drive by 3d Printed Life
https://www.youtube.com/watch?v=Emvo3bLT-Z4

Balisong Scissors by Contraption Collection
https://www.youtube.com/watch?v=mQhm9aX8l38

Jitterbugs by Shang Ke
https://www.youtube.com/watch?v=HZvQ35DDeGs

Repairing Vintage Safety Glasses by Switch & Lever
https://www.youtube.com/watch?v=SQfrIi5AnAo

-=Tips & Tools=-

What happens when someone steals your design by Make Anything
https://www.youtube.com/watch?v=ly02Lve1K0s

Mark Setrakian interview by Tested
https://www.youtube.com/watch?v=NsFBHqbNKvA

3d printing deals at HF by Uncle Jessy
https://www.youtube.com/watch?v=yPLAmqLY-9I

Turn images into 3d prints by Print Dogs
https://www.youtube.com/watch?v=aVirbHHsMuc

-=Digi-Key Spotlight=-

C/C++ on the Raspberry Pi Pico
https://www.youtube.com/watch?v=B5rQSoOmR5w

Transcript

This week on maker update: CNC Routing on the cheap, a wiggly gearbox, creepy robots, Jitterbugs, Vintage safety glasses, and what to do when someone steals your design.

Hello and welcome back to Maker Update! I’m Tyler Winegarner and, you’re awesome. I just thought you should know that. Here in New York we’ve got spring in full effect, trading our snow shovels for lawn mowers and of course we’re up to our shins in pollen. We’ve got another awesome show lined up for you, so let’s check out the project of the week.

DIY CNC router projects aren’t especially new. But a CNC router for just $50? Now you have our attention. This seemingly impossible task to build a desktop CNC router for just fifty dollars is from DAZ projects.

I hate to be a naysayer, but if I read about this project on paper, I’d never believe it would work. All of the linear rails and slides are 3d printed. The lead screws are made of threaded rod. The axis motors are these small geared and very affordable 5v stepper motors. The rest of the machine is made from plywood panels, cut by hand using paper templates as a guide. And yet, it all works – and seems to work pretty well. Sometimes, it feels good being wrong.

Of course, with the linear rails being 3d printed, you’ll need a machine that’s very dialed in before smoothing the parts with some careful sanding. One of my favorite tips is using plastic beebees to function as bearings for the linear slide. They also show how to modify the steppers to function as bipolar steppers to get more torque from them. For the electronics, they’re using an arduino uno with the grbl shield to drive the steppers. and the spindle is a DC motor. 

The video finishes with getting to see the machine in action. Unsurprisingly, it’s not fast, and when cutting denser materials like acrylic, you can see some deflection in the spindle. That’s not terribly surprising considering how the machine is built, but after seeing some of the initial pieces coming out of this machine, its clear it can still keep its accuracy if you take your time. Its a great testament to the spirit of just trying something instead of…  well instead of listening to a bozo like me. If you want to build your own, you can find all of the parts and plans on Thingiverse.

At the other end of the CNC Router spectrum, Carbide 3d has just announced the Shapeoko 4. The biggest change from previous versions is the new hybrid bed, featuring alternating slats of MDF and Aluminum T-Slot rails. This should afford a lot more workholding options, including the ability to clamp your workpiece from the side, giving you complete access to the top of the work piece. They’ve also beefed up the Z-axis with a lead screw, and widened the x and Y axis belts to further eliminate stretching and defection. Like previous models, the Shapeoko is available in three different sizes, starting at $1700.

More projects! In his quest to build an affordable and compact robot arm, Andrew from 3d Printed Life built a strain wave gearbox as a compact solution to get more torque from otherwise cheap nema 23 stepper motors. This is a completely wild design that uses a flexible gear and this internal wave generator to transfer the motion between these two halves of the housing. His goal is to design it so it can deliver 10 newton meters of force so that the arm will have enough power to move his camera. What I love about this video is how he reveals not only how he engineered the design, but also how he tested it to make sure it’ll hold up to regular use. 

Speaking of iterative design, over on Youtube I found this video from Contraption Collection about their pursuit of designing what they call baliscissors – a pair of scissors that unfold like a butterfly knife. For these to work, the hinge needs to spin freely and then lock into place. And it needs to have as little extra play as possible in the joint so it doesn’t wear itself out over time. This isn’t their first version of this hinge design, but with a little luck, it might be the last. It’s a good lesson in the importance of having just the right tolerances. 

Also on Youtube I found this fun and educational video about Jitterbugs by Shang Ke. No, not that kind of jitterbug. Jitterbugs are *clears throat* “Moveable, over-constrained polyhedra”  – you know, the shapes that move kind of like this. She dips into a little bit of the history of jitterbugs and explaining what degrees of freedom actually mean, before showing you a bunch of different ways to make them yourself. It looks to my eye that that crazy folding door design is derived from  these shapes, but I can also imagine that there’s a treasure trove of kinetic sculptures that can be made from these designs.

Tool restoration isn’t exactly a new thing. But I don’t think I’ve ever heard of a restoration being done on old safety glasses. Daniel from Switch & Lever has this video on how he restored this old pair of safety glasses. As you can imagine, the bulk of the work is removing all of the scratches from the lenses – but there’s a ton of great tips along the way – like using warm water to soften the plastic to make it easier to pop the lenses out to using these micro mesh polishing cloths, with grits all the way up to 12 thousand. Its a lot of work, but seeing the crystal clear finished result is super satisfying.

Time for some tips and tools, and we begin with a video from Make Anything on a subject that could happen to anyone who shares a project online: What do you do when someone wants to copy your design to sell it as a product? This video is a great exploration of the fine line between intellectual property and working in the world of open source. What constitutes an original design? Who owns the rights to a derivative design? And what do you do when you want to protect your rights as a creator, but don’t want to deal with a legal battle? I wish I could tell you this was a fun video, but it’s worth watching all the same.

Over on Tested, I found this interview with Mark Setrakian. Mark is a robotics designer with a ton of animatronics effects credits  from feature films, and plenty of trophies from robot combat competitions. Mostly I know of him from this amazing art piece used to display the trophy from Battlebots. I’ll be honest most of this is still way beyond me, but Mark does his best at explaining how he designs the motion for his robots in a way that’s fairly easy to follow along. Don’t miss this one.

Replica Prop maker, 3d printing enthusiast and my neighbor Uncle Jessey just released this video about the best Harbor Freight deals for avid 3d printer users. Harbor Freight is normally where you’d buy cheap trim routers and maybe some questionable jack stands, but there’s some genuinely good stuff there – but its not the first place you think of for 3d printing supplies. A lot of his suggestions here are consumables – super glue, safety glasses, chip brushes, stuff like that. But suggestions like the 12 outlet wall mounted power strip and the airbrush kit make this video a goldmine.

Finally, we have a video from print Dogs answering the most basic design question I see asked in 3d printing groups: How can I turn this image into a print? They talk you through the basics, like converting your raster image to a vector file, then using the extrude tool in Fusion 360 to turn it into a printable design. You can use this for making art, cookie cutters, and plenty of other application. And I’ll be honest, I wish more 3d printing tutorials were offered by these two adorable dogs.

For this week’s DigiKey Spotlight, we’re checking in on Shawn Hymel’s series about the raspberry Pi Pico. I’m sure you already know that you can program for the Pico using Micropython and the Arduino IDE. But you can also write for the Pico using C and C++ using the Pico SDK. Not only might this be a more familiar programming environment for some folks, but it will also allow you access to both cores on the Pico. There’s a lot here just about how to get your computer set up with the appropriate SDK, but then he walks you through your very first Blink program in C++.

All right and that is going to do it for this weeks show! Thinking back on the Jitterbugs and Wave Strain Gearboxes, what are some of your favorite mechanisms to watch, or ones might you want to use in a project someday? Let us know down in the comments. While you’re at it, be sure to subscribe, give us a thumbs up, and sign up for the Maker Update email list so you don’t miss the next one! Thanks to Digikey electronics for having all the parts and making this show possible. Take care out there, and we’ll see you soon.