Recycling with CNC: Soda POP Robots

Can you Machine an Aluminum Can?
Yes you can!
(Project Files and build details are below)

Japanese Paper Craft was the initial inspiration for this project, and several years ago I adapted a Paper Robot design from paperrobots1999.com to fit onto an Aluminum can, this was before the Nomad and I had to print the design on Sticker Paper and then cut them with scissors. The Down side was that I could never cut them accurately or repeatably to confirm my design, so it got put in a project box and forgotten for 5 years.

Now, with the Nomad, whose middle name is Accuracy and Repeatability, I can make Shiny Metal Robots all day long!
Heres the Final Robots and Parts:


Coke Vs. Pepsi Vs. Nomad

Carbide Create Design File


To help fold the small parts I first ran a toolpath of all the holes, which included the Axle holes, but also holes at all the fold points.

Carbide Create Cut Preview:


All the parts to build one 3" tall Articulated Robot, including a spare Helmet and some extra Hips and Shoulders.
The aluminum can canvas measures 8" x 3.6" x .005"

Work Holding the Aluminum Can:


For Metal, I usually go with the Blue Wax, but even after Sanding the thin plastic layer and wiping the can with acetone, the wax would release the aluminum sheet during the cut. ( I think the thin material wont hold the necessary heat to bond with the wax properly)
Hot Glue does work to Hold the Aluminum, but introduces a Challenge of an un-even work surface.
The Solution is easy though, I set my DOC to .045" which put the tool into and through the .005" aluminum across the bed- regardless of the .030" variation found across the work.
I zeroed of the Acrylic wasteboard, and then jogged up .046" and zeroed the z again.
FYI: Rubbing alcohol will release Hot Glue, but it cracks acrylic. If you look closely at the video you can see the cracks at the bolt holes.

The Exploded Parts/ Construction sketch

Under 20 cents in Raw materials!


Fold, Pinch, Repeat. I placed an extra tab wherever possible, so you just fold the parts into square tubes, and pinch over the final small tabs. (Kinda like a Tonka truck)
Resistor wire, some PCB donuts, solder and a spring.
Boom, you got a Robot.

The Stop Motion Secret:


The Key to getting the Robots to stand up is Friction created by internal tension. I was able to create this by capturing the hip joints by soldering PCB Donuts onto either side of a resistor and then winding a small spring (a retractable pen spring will work) into the body.
I could never have planned for that to work, just one of the results of fiddling around until it does. :relaxed:

Heres a link to the Files:

If you have any questions let me know!


If you have too much fun with these, also let me know.

14 Likes

Very cool!

My Uncle Walton taught me to recycle/repurpose cans by cutting off the tops, then cutting many thin, uniform strips from top to just shy of the rounded bottom — one would then coil the strips just so, so as to make legs and a back to form them into furniture for dolls. Kind of amazing to me now that one would do that, and then hand such a thing to a young child as a plaything — I don’t recall my sister getting cut, and she also helped make some of them (you could combine multiples to make love seats and sofas).

2 Likes

Wow! That is too freakin’ cool-and ecxcellent practice for machining metal veneers-and something my boys will love to do! Whimsey, fun, cheap-and a great learning experience-You Rock!..
Now this will be like the song I just can’t get out of my head…:scream: only much more fun!
Thanks!

1 Like

Heres a link to the Project in the Community section at Make:

2 Likes

Very nice project.

And now on Hackaday (https://hackaday.com/2017/03/26/cnc-turns-empty-cans-into-action-figures/ ) , with the usual HaD comments of “My gradpappy did it with nothing more than half a toenail clipper and two sticks rubbed together for a soldering iron”.

Very nice. For the fixturing of thin material using hot glue, an iron works fairly well. Takes some practice to get the temperature set right and to slide the iron off without letting the material move. The trick is just above the glue melt temp and slide off slowly so the glue sets without the material lifting. For 0.25mm (0.010") copper, it isn’t too hard to maintain flatness or about 0.1mm (0.004") or so, if the waste board is flat and the material is not creased in the first place.

2 Likes

Loved this! seen it on youtube yesterday :+1:

2 Likes

I’m curious to know if you tried spray-on glue to hold your work piece? Maybe they don’t work well on metal but if they did, it would be quick and provide a uniform surface.

Definitely going to give this a shot on the shapeoko, I love it!

I think this would be a good candidate for the old superglue and masking tape trick for workholding?