In January 2016 I was working on an old idea that I abandoned years ago - trying to weave a basket using a 3D printer. During this, I came up with an elegant and unusual way of printing that I have never seen anywhere before.
I call this method "Es-Cage printing".

On this page I will show you how I developed and refined this method and how it can be used to create amazingly strong structures that are very light, and can also be printed pretty fast.

You can find a tutorial on how to create these structures here.

  The method is based on the fact that an FDM printer can "jump" over an empty space while extruding a strand of plastic, much like a spider. This is called "bridging". It works best over small distances up to 2.5 cm / 1 inch.

The principle is best explained using the easiest shape for this method: a simple cylinder.
As you can see in the picture, the model is made up of several "stages" that have indentations. Each stage contains parts of an inner AND an outer shell, connected by "radials".

The trick of Es-Cage printing is that each stage is modeled so that the next stage will have exactly the same radials, but "switched" inner and outer shells. Basically, the printer is printing "zig-zags" all the time, alternating between zig-zagging and zag-zigging to form the stages.

  These structures can all be printed in one continuous (spiralized) movement of the printer - no travels (=jumping from one point to another), no fill, no support structures. This means the prints come out clean, and print time is relatively low compared to normal printing.

The amount of radials can of course vary, as can the height of the stages and the thickness of the resulting "wall".

Let me take you on a quick trip through how I expanded and improved this new technique - new to me, anyway. (Anyone done this before? If so, please let me know !)



  The next step was to find out how to get around corners to form square shapes. There are several ways to solve that, this one seems to work well.

This cube is 4 x 4 x 4 cm. It has 8 stages, each 8 blocks per side.
The "wall" is 5 mm thick. Printed with a 0.4 mm nozzle (shell set to 0.5 mm for extra strength). It took about 30 minutes to print.

Printing these first tests, I was amazed with the strength of these flimsy-looking structures. So I did a little test: I put the cube on the floor and stood on it...

It can take my weight (some 80 kg) without cracking or deforming !



A spherical shape turned out to be a bit harder to model. This first one took me quite some time....

I have since developed several other ways to model these structures, and it would not nearly take as long to do another one now - as usual.




Next I had a go at combining these shapes. Again, I found some better ways of doing this later on, but only because I did these first...

Merging the cube and the cylinder was not so hard. Merging the cube and the sphere was a lot trickier. As you can see, the intersection of the two shapes crosses through the "planes" of the shells, which makes things more complex.

Once a model is finished, it is quite easy to deform it. In the pictures you can see the first example of applying a "twist" operation to the model.



By merging two cylinders and adding a bottom I produced the first useful application of this technique: a lovely desk organizer.


They are now available in my shop and in my webshop.


Then I took some time to explore more complex shapes for the "planes".

This resulted in a very nice series of lamp shades.

You can see them all properly on this page.

I made separate cut-out tops for each model, as I like to shape the cut-outs to (sort of) match the pattern of the lamp.

All these lamps (and other examples so far) are printed "spiralized".
How to print cut-out bottoms while printing spiralized will soon be explained in another tutorial.




As you can see, there are endless possibilities to fool around with this technique. The main restriction is that the bottom of each plane MUST be a straight line, as this is where the printer is bridging over a gap.
(In the pictures this is the TOP of the planes, as the lamps are printed upside down.)

  It is also crucial that the radials of the stages match up exactly. These radials form the "beams", which are held together by a kind of woven or "wicker" structure. It is these beams that bind the stages together, so the radials of each stage need to fit exactly onto each other.

There are several ways to accomplish this, however none of them are easy. See the tutorial for more info.

The radials can also have some "body" to them, instead of just a single line. In fact, that is how I came up with this technique - see the "wicker" pattern in the basket shown here. This will lead to a more "woven" structure, as opposed to the earlier examples, as the planes cross over each other.
You can see more baskets here.



  I then took to modeling other products using this technique:
      lighter cases, a pen, bracelets, earrings, rings,
         tea light holders, a necklace with a led inside a bead,
              and there's more to come...

Visit the shop or the webshop to see them all in detail.

What I really like about this technique, is that although the printer moves in one continuous movement ("spiralized"), it is possible to create an inner and an outer shape which are quite different from each other. This way it is possible (for instance) to create a lighter case which has a curved outside, but a straight oval inside, so it fits perfectly around the lighter. Normally, a single shell print will have the same shape on the inside and the outside. Es-Cage printing removes that restriction !

  Here's some tests I did to see how this method would work at smaller scales.
The planes on the largest cylinder are +/- 1 mm. The other cylinders are printed at resp. 80, 60 and 40% scale.

At 100% the wall still has holes in it, best seen when held up to the light as shown here.

At 80% these were almost gone, and the two smallest ones had no holes anymore, although they still show the pattern.
And they are still amazingly strong....

....which leads me to think that there are possibly all kinds of applications for this technique outside my field of expertise.

So if you think Es-Cage printing could be useful to you, please let me know.



  For a "pièce de résistance", I made an Es-Cage castle.
Just for fun.

You can download some of these models here.

Please read the instructions on the model pages before printing them !

I hope this technique will be useful (and fun) to many makers in the world.

I also hope that someone is able to create an algorithm for this method, so that it might become possible to add Es-Cage printing to Cura and/or other slicer programs. It would be great if you could just load a solid model and tell the slicer to turn it into an Es-Cage print according to some settings... unfortunately I'm not that kind of boffin - but I'm sure there are people out there who would be willing to give it a try? If so: let me know !

  If you want to learn how to model these shapes yourself, read the tutorial.