Tag Archives: Colonna

08: 3D Etching

This week I decided to give 3D etching another shot. I have just once before played around with the 3D settings available on our laser, but I haven’t really explored the process until now.

Normally, the laser interprets shades of grey by preparing a halftone map and etching that at whatever singular power I have set. With the 3D feature enabled, the firmware will adjust the power of the laser depending on the darkness of the grey: white is ignored, black is etched at your selected power. Because of this, all you really need is a depth map and you can 3D etch straight away.Just remember: white is shallow and black is deep!

The Abecediary logo with the core etched away

Back when I first tried it out, I just used some sample depth maps available in Google’s image search, but this time I created my own typography-themed art. I had to use Photoshop to create some raster effects to create the sloping edges I wanted because there isn’t an easy way to create shape-burst gradients in Illustrator, but this wasn’t a problem because, while the laser won’t cut anything that isn’t proper vector data, it’ll etch even raster graphics with impunity.

ABCD Layout
The blurry edges are where the 3D happens.

I often use the simple Abecediary logo as a sample design when testing new materials. Even though the white melamine-coated MDF I used wasn’t a new material to me, I felt it appropriate, so I created a black version with a white inner glow. The thin red line is the vector cut that created the final shape of the letters after I hollowed out the core. Because I etched five passes at a fairly strong power, the finished piece had too steep a slope; you can hardly see that it was a slope and not just a really deep etch, but it’s there! I swear!

Etaoin in MDF
The whole piece; the depth is hard to capture without appropriate lighting.
Etaoin in MDF
The slight lip on the edge was made by skipping a few lighter levels of grey.

The second piece, ETAOIN SHRDLU, was based on a fun part of newspaper lore and set in Colonna. It was etched opposite the ABCD: the letters were left untouched while the outer space was etched away. I chose a thicker gradient stroke so that the slope would be gentler. I also only etched the bitmap four times. The contrast between the white letters and the resulting grain of the MDF’s innards is profound. It almost looks like the letters are sitting in a bed of sand that has settled over years.

Etaoin in Black
The black acrylic Shrdlu is a little hard to read without the right light reflected!

The final piece was cut from quarter-inch black acrylic. For fun, I created an offset path so that the letters would be cut out more tightly than the MDF version’s square border. Even with six passes at full power (and half-speed) the etch didn’t quite reach half-way through the material.  The result is a little hard to read (maybe I should have used a capped material!) but certainly looks neat.

Etaoin in MDF
The slight lip on the edge was made by skipping a few lighter levels of grey.

The amount of passes necessary to create a good 3D look takes a lot of time, but there’s a whole lot more that can be done than just beveling the edges of pretty type faces. I’ll definitely be playing more with the 3D mode as we go on.

Etaoin in MDF
The sand blows away, revealing pure white type!