Computer Controlled Cutting

This week assignment deals with design and make a press fit construction kit, using a laser cutting tool. I was inspired by models of pyramids shown in the Figure. So I decided to build a pyramid with equilateral triangles and four faces, because an n-sided base will have n + 1 vertices, n + 1 faces, and 2n edges.

First I used Microsoft Visio to make a rapid sketch to define the dimension of each face of the pyramid and the dimensions of single equilateral triangles

Draw with Rhino of the individual triangles and the press fit piece

The final design (in red). Considering the offset of the laser beam I had to resize the press fit piece to compensate for laser beam cutting

Another two laser cuttings, in cardboard for models and in acrylic.

Laser cutting, parameters for acrylic are, speed=10, power=100, frequency =500, resolution=600

Laser cutting of the kit. I used a soft foam and the assembly of the pyramid faces was easy, because the foam stretched a little when I placed the prees fit piece to joint the individual triangles

But assembling together the faces of the pyramid was not easy, because for this purpose the press fit piece was to much soft. I`ll try with other materials for this type of joint.

Tetrahedron's assembly and installation of the darkness sensor designed at the end of this assingment

Also I designed a pcb with OrCAD and generated a Gerber file and export it to Corel for cutting solder side and solder mask of the pcb

Vinyl cutter, cutting copper clad solder side and vinyl for a solder mask for the previous design. This was really a test, because I must use some film for preparing a silk screen frame. This procedure could also be use for preparing a stencil for applying solder paste to SMD

I made the transfer of the copper clad on plastic cardboard. It's something difficult, but helps a lot if you make some cuts to the copper to be removed.

Final Comments: I'm just beginning to explore laser and vinyl cutters. I also prepared some draws for engraving acrylic with the laser cutter, and I think that could also be used for engraving pcb.

Thank you