4. Computer controlled cutting

Today’s Menu

New week, new chapter. Now it’s getting serious. The goal this week is to get cutting. We’ve learned how to use several different machines to do a variety of tasks. Some of those tasks were a group effort, and some we did on our own.

Cutting vinyl - making stickers

This was the most straightforward part of the assignment. The First step was to receive a vector graphic of my lab’s logo from my PostDoc, whose design it was originally.

The original SVG file is available here.

(This was all a bit of overkill - I’ve since discovered a much easier way to do this.)

Hardest part of that was getting Inkscape and X-windows to work on my Mac. After a certain amount of swearing and plenty of patience, we got there in the end. Once in Inkscape, I then had to save it as a DXF file using the option shown below.

Then it had to be opened with the vinyl cutter’s own “Silhouette” software, which loaded it as an outline. This was then surrounded with a rectangular box, as shown.

This was ready to be sent to the machine. A grey coloured vinyl sticker sheet was sourced and stuck to the template provided with the machine, taped in place along the edges with masking tape. The template and vinyl were then fed into the cutter. The cutter blade was tested on a small piece, and we found that it had to be set on depth “3” in order to cut completely through the sheet.

The printer was then turned loose with the file and it generated the desired pattern. On completion of the cutting, the vinyl and template were removed from the machine, and sticker was peeled off the template. First the negative was peeled back, carefully using a sewing thread cutter to hold down the delicate parts, and then the same thread cutter was used to separate the centres of letters and some of the contained parts of the logo. These were then stuck onto the lid of one of the lab’s Macs.

Masking tape was then laid over the positive cutout and peeled back with all of the delicate elements intact, and used to transfer the logo to the lid of a second Mac.
the original file is on icloud

The final result is gorgeous.

Epilogue

I took these skills to Africa and ran a workshop on soft robotics. I took a Silhouette to Ho and used it to show the students there how to cut various bits of plastic, paper and fabric. You can see some of the moulded soft-robotic grippers they made on the table in the picture below.

I left the vinylcutter there. I’m keen to see what they’ve done with it since.

Engraving with a laser cutter

This is a group activity, so I’ll rewrite it after we’ve done the exercise together, if I manage to be part of this year’s group.

Cutting with the laser cutter

Safety around the lasercutter is paramount. Our instructor had got sidetracked with something else while we were making our first cuts, so I casually went over and picked up the fire extinguisher from the wall. Carrying it quietly across the lab quickly got his attention!

Preparing the print job

Calculating the kerf of the laser beam

Parametric Design & Cutting

(I think I did the scuba cart parametrically - dig out the documentation for that from 2019)