It seems like we should be able to make this

Extra points for fewer layers?

Oooh! I gotta make me one of those…that would be a fab stress reduction toy! :smile:
(I wonder if I even remember how to use the 3D printer after all this time? ROFL! I’ll have to go back and re-read my own tutorials.)


I actually have one of these 3D printed in place using SLS. And let me tell you, it is spectacular.





Pictures should show you how to build it if you’re so inclined. It’s currently scaled for .120" (1/8") baltic birch.

You’ll want a hammer for driving the pins.

Sand your wood really well prior to cutting, to about 400 or more. You want really smooth surfaces.

Use a lube once assembled. I had feed-n-wax laying around, it worked nicely.

No glue in the assembly. Everything friction fits.

The “oval” pieces in the tracks benefit from a bit of extra sanding once the parts are cut. You want them to move freely in their slot, so making them just a bit thinner helps.

Test fit everything and ensure things slide nicely before driving any of the pins in place. Pins are one-way. Once you hammer them in they will not come out without breaking.

(EDIT: re-uploaded the files because the first one wasn’t showing the other circle you needed, it was out of the work area.)


Nice work on the cross-connectors! (and the rest of it)

Thanks! :slight_smile:

Nicely done! (And in record time!) :smile:

If anyone grabbed the SVG already, go grab it again, there are 2.

Nice! I made a little prototype design last night that came up short, but I think I’ve dreamt up a way forward. It’s a very different design from yours, so I’ll probably go ahead and see if I can make it work. One of my favorite design goals is creating “pure” GF designs that don’t require outside parts, and I love that you’ve done just that!


Looking forward to seeing your design! Hope you post the fail too, I learn a lot from all of our mistakes, sometimes more than my successes.

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That pin design is great!

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You’re assuming my next tweak won’t end as a fail as well? Wow, the confidence! :wink:

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A progression of prototypes…

Top row left to right, then bottom:

  1. First idea, channels are far too rough for operation. I still like the basic idea, 2D cuts forming a channel.
  2. A complete refactor using layers. Works well, but is unstable.
  3. Stable and enclosed. Works very well, but is quite complex to assemble due to end-caps, and somehow it just isn’t as fun to rotate.
  4. Okay, now we’re talking! Stable and open-ended (since it’s fun to see the linear guides peek out).

Another view:


Very neato-bandito! (I like the black one too - pity it’s sticky.) :grinning:

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I have been taking a step down that road for a different reason. I would like to make a box for all my carving tools but there are four different types and lengths and diameters of handles so each set needs its own rack, holding the handle the proper distance but open so you can see which is which…

So far so good, that part is sorta easy, but with the box open they should all be upright, and closed would be two layers facing opposite directions and of course the challenge is the mechanism.

Early on it becomes that there cannot be a single point of rotation for any of them and that is where this little exercise comes in.

Oh and to take a quick diversion, having to test my blood every day, the lancets have a top like a flying saucer round .25" diameter with the “cockpit” part 0.125" diameter and thus it becomes a very interesting spacer. Being of plastic it is low in friction as well.

So back to the main thread the question becomes what paths can the spacers take so the four boxes go from two rows of two layers horizontal to one row vertical without locking up on the front, back, bottom, or each other simultaneously.


I knew you wouldn’t be able to pass up that challenge. AND that whatever you came up with would be awesome. :heart_eyes:

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We had one when I was a kid that was called the “Do Nothing”. A buddy came to our house before each sailboat race to give it some turns. He thought that it gave him good luck. I should add this to my list to go gift to him.


It might make an interesting beginning for a bilge pump? It would bring good luck and make the boat go faster (if there was a slow leak anyway)

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