• Robert Buehler

Digital Fabrication: Vector/Raster Layers with the Laser Printer

Updated: Feb 4, 2019





PROCESS:


Tracing the original illustration in Rhino

The Elusive Golden Woodcock, 2019

The work I chose to translate in this first Rhino experiment was my Elusive Golden Woodcock pen and watercolor illustration. Naturally, my intention in taking Digital Fabrication is primarily to find application and means of integration for technology within my existing practice. It was important for me to learn first how to directly translate my art into vectors - a standard start point. I imported the scan of the original illustration as a background bitmap into Rhino 6 and began the time-staking process of hand tracing the contours of the drawing using the pen and curve tools. I estimate I logged between 20 and 25 hours just translating the contours into vectors, re-positioning the points and curves, and adding further detail to the various elements of the drawing. I broke the vectors into three primary layers. The first layer was reserved for just the entire outline. I wanted to be able to apply the form as a simple silhouette, and keeping those vectors separate allowed for easy isolation. The second layer contained the insect/leaf lace perimeter. This layer was secondary to the initial illustration and I wasn't completely sure I wanted to use it. More than anything, it was an experiment using the mirror and array tools. The last layer contained all of the negative-space vectors which described the leaves, pine needles, insects, and details in the woodcock and phallus.

Translating the Rhino file to Illustrator I knew that I wanted to give printing a raster layer a shot in this first project, and so I needed the image to save along with the vectors, but I struggled with transferring my background bitmap image from Rhino to Illustrator. It's something I am actually still wondering about. I know there must be an easier way to accomplish the task in a way that doesn't separate the image from the vectors... I ended up just exporting the curves/vectors as an Illustrator file, and then uploading the scan of the original illustration into Adobe Illustrator separately. It took a few minutes to resize and align the image with the vectors in Adobe, and I'm not confident it was as perfect as it could have been, but I got pretty close. It's something I'd like to figure out and I'm going to come back to this, for sure.

Laser Printing Trials (Raster and Vector)

ABOVE: laser-cut insects, leaves, and bird silhouette on Washi paper / BELOW: raster layer on translucent Opalux

I chose a 19" x 24" sheet of Canson Opalux Translucent Paper, and a Handmade Kozo Washi Paper I made during my 2014 study abroad in Japan, as materials for my initial laser trials. The Opalux presented certain challenges from the get-go. I first attempted a small rectangular vector cut in the excess portion of the paper. Reacting to the heat of the laser, the corner of the sheet actually began curling as the laser was cutting, and ended up creating a crispy and curved rectangle. I knew from this, that attempting to execute the many intricate cuts I had planned out of the Opalux would not go well. I scrapped my initial plan and chose to experiment with a raster rendering of the original illustration on the waxy paper. After a quick two-inch trial, I decided to give the full-scale raster a go. I anchored the perimeter of the sheet with metal rulers and tape, and used settings close to "Waxed Graphing Paper" in the database (Speed 100, Power 40). Then, before removing the sheet from the bed, I weighted the rastered portion with a small wooden block and cut the work from the sheet using the lace layer's perimeter vector (Speed 85, Power 30, Frequency 20). With the paper weighted on both sides of the cut, curling was minimal and the cut came out clean. The Washi was a much more straightforward material to work with. Because it's paper that I produced from start to finish, I understand the very fine fibers that form its structure and the potential for varying thicknesses between each handmade sheet. I set the Speed to 85, Power to 30, and the Frequency to 20, just like I had for the Opalux. The Washi is notably more fibrous and not as dense, but the weight of this particular sheet was quite similar to the Opalux and the settings seemed appropriate for both. For the Washi, I sent all of the vector layers over to the laser printer.

Frame Construction, Assembly, Display (in progress)

Laser-cut Washi and rastered Opalux layers, sandwiched between three 12" square panes of glass, with backlight.

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