WEEK 3 - Computer-controlled cutting

Assignments: Design, make, and document a press-fit construction kit


So this week's assignment is to make a press-fit construction kit out of cardboard. Good, sturdy and flexible cardboard. Since we received our laser cutter not too long ago, finding thick cardboard wasn't that hard..

I first measured the thickness using a caliper, 6.48mm thick. I then used this measurement and Illustrator to design a comb test pattern with various width. 6.48mm all the way down to 6.2mm. To make sure I had a clean border to test with I also cutted a 20x20mm square.

Using Trotec's Job Control cardboard preset didn't cut all the way through so I had to reduce the speed a little for a clean cut and my first design couldn't hold the test piece at all.. I had to design a second comb with much smaller cuts, decreasing by 0.1mm instead of 0.05mm.

It was a wise choice since the fit was perfect somewhere between 5.7mm and 5.6mm.. the last 2 values on my test pattern.

Now that I knew the width of the cut, I was diving into designing the kit. I was torn between trying to design something complex using Blender's parametric plugin Sverchok or doing a simple block that could be shaped into wathever I wanted. I opted for the second option. I wanted to create organic structures that could quickly be assembled using a single block design. I went for 5cm hexagons with 1cm deep x 5.7mm wide cuts.

Being a big yoga fan, I decided to build a structure that would embody natural balance. I opted for my favorite yoga pose, the famous Poireau.

So here's my sculpture on a table.

My sculpture on a CNC.

My sculpture on a laser cutter.

My sculpture on a workbench.

Vinyl Cutting

Our Vinyl Cutter is an old Roland DG Camm-1 PNC-1000. We had an old laptop with a parallel port laying around in the lab and we setted it up so we can use it as a remote desktop. I prepared the vinyl cutter manually drawing a small rectangle to see if the pressure and height of the blade was fine.

I decided to vinyl cut the same design I made for the laser cutting. Inkscape can export as hpgl natively and the Camm-1 is waiting for it. Time to send my HPGL file to the parallel port...

copy "file path" LPT1

Once everything is cut, since we don't have real transfer paper, we usually use the same blue tape we use for 3D printing. Works perfectly most of the time.


Peeled off the sheet

rubbing all over so it adheres well and to remove air bubbles

Peeling the "transfer paper" really slowly at an angle

And the final product!