Kirigami Honeycombs

Intro: Kirigami Honeycombs

Honeycombs can be found in a vast variety of structures, especially as core infill for composite sandwiches used in aerospace structures as well as your everyday kitchen door. For certain applications it is useful to have section-varying honeycombs to perfectly match your profile. Here we introduce a simple and efficient method to produce variable cross-section honeycomb structures from a simple sheet of paper. This is achieved using kirigami, which is a close variation of origami. The main difference is that kirigami also includes cutting of the paper rather than just folding it like in the case of origami. This powerful technique can be used for many purposes, and is not only limited to paper sculptures or pop-up booklets as you will see in this Instructable.

STEP 1: Print the Pattern

There are many ways to cut and etch paper. A laser cutter would propably be the fastest and most precise way to do it. I went for the straightforward ruler and cutter, so that everyone can replicate the process as long as a printer is available. First of all print the pattern in attachment. This is the pattern for the cheesegrater honeycomb to be seen at the beginning. I will explain at the end how to create your own honeycomb. You will notice a specific color code:

1. blue = mountains
2. red = valleys
3. black = slits

STEP 2: Cut and Etch

Following the provided color code, with a ruler and a cutter (or by hand if you are skilled enough) slit the black lines (slits), and etch the blue ones (mountains). The red lines (valleys) have to be etched on the the other side of the sheet of paper. You will notice that the slits already provide the guidelines you will need to follow, although the pattern has not been printed. I normally avoid printing the pattern on both sides as they always tend to be mismatched.

STEP 3: Fold and Glue

At this point you are completely set up to start folding your honeycomb:

1. Fold along the mountains and valleys as in the first picture
2. Once you have folded the paper in one direction you can do the same in the opposite one. You will notice that the structure will fold pretty naturally
3. Glue the matching faces together and repeat until the last row is glued

And there you go with your ready-to-use folded kirigami honeycomb.

STEP 4: Custom Cross Sections

To build your own honeycombs with variable cross sections, download the Dynamo or Grasshopper definition attached. All you need to do is define the cross section curves taking care that the end points lie on the same vertical line. The integer slider defines the number of cells in the horizontal direction. Once you've defined the unrolled strip, you will have to mirror and copy the pattern depending on the width of your final honeycomb, print, fold, glue and enjoy!

For those of you interested in the implementation details give a look at this paper.

Comments

[jeanniel1]

Awesome. I love how this can be done with one sheet of paper and manually.

[kebmoore]

I love this! Do you have a way to skin the honeycomb to make panels and other shapes?

[bcavaciuti]

I reckon you could do it a few ways... add flaps to the cut outs edges and glue them. Try gluing straight to the edges with a gummy thick glue.
you could also borrow a technique from old model aeroplane hobby manufacture: Use tissue paper lain across the hexagons(pre glued) then soaked in glue (watered down pva or other not sure) and leave too dry and as the glue dries it shrink wraps the tissue paper onto the frame taught! this could then be built upon with more paper/card or fibreglass and bondo?

Or research how they affix it in cheap doors and other applications the same construction.

[riclamagna]

Top! I like your approach!

[riclamagna]

Thanks! A large area can be subdivided in many subsections and then easily assembled back together. As I've mentioned in the previous comment you need to take care that the cell sizes remain constant, or you won't be able to correctly align the single patches together. Skinning is normally done with glass or carbon fibre mats which you lay on the frame and then laminate with epoxy or equivalent resins. bcavaciuti also gave some advice.

[BigSpin]

I'd like to use this for a lightweight portable profiled theatre stage, making a larger area in sections. Do you have an idea how I could make larger versions? I have access to a laser cutter but I would like to make this with cardboard from produce packaging boxes.

[riclamagna]

Sure. All you need to do is divide the profile curves of the area into the number of sections you want. You would then follow the production steps for each section and finally assembly the whole structure together. Make sure to keep a constant size of the honeycomb cells, or you will end up with misaligned elements.

[dpizetta]

Hey, nice assembly! This will help me a lot. Some time ago I've made a wine cellar based on hexagonal forms, but the manner I build was to wasteful. I put your link in mine Instructable, I think it will help people to build this. I hope you enjoy the idea :) And tks for sharing your work. https://www.instructables.com/id/Honeycomb-wine-cellar/

[riclamagna]

Nice winecomb cellar! For this kind of application I believe you will need to use a stiffer material and somehow fix the joints, as you are loading the honeycomb in-plane rather than perpendicularly to it. The risk is that it will just fold onto itself under the weight of the bottles. Cool application though!

[crank_girl]

Do you have a pictures of these in use?

[dpizetta]

This could be a use :) https://www.instructables.com/id/Honeycomb-wine-cellar/

[riclamagna]

I am currently working on some applications. I'll upload images as soon as I have something ready.

[EngineerJakit]

I really like the potential for this, but i have no idea what kind of file this is, nor can i open it.

[riclamagna]

Hi EJ. The *.gh file is a Grasshopper file. Grasshopper is a visual programming language for Rhino3d. I have written an alternative version in Dynamo, also a visual programming language, but for Autodesk Revit or Vasari. I had to take the Dynamo file down as I realised there is a bug in my Python script. I'll upload it again as soon as I've fixed it. Hope this helps you further.

[MsSweetSatisfaction]

Woah this is amazing! I kind of want one to help me keep my desk organized and yet stylish! Do you use the finished combs for anything?

[riclamagna]

Thanks Ms! Yes sure, I use them mainly as infill for composite
structures, a pretty straightforward engineering application. But they
work very neatly as pen holders too!