Introduction: Creating Stacked Acrylic Landscapes From Digital 3D Topography
This is an Instructable about a piece I made recently at the Tech Shop in San Jose, CA. (Website here!)
The piece, titled "Mementos," began from the feelings I get when moving away from a place or city that I have grown attached to. I was inspired by the historical habit of keeping a lock of hair as a memento of a close friend or family member. The final stacked acrylic pieces are each of a separate place that is significant to me, and my own hair is encased in-between the acrylic, symbolic of my feeling that a part of me still resides in those places.
A lot of my art involves topography, mostly of my own MRI images (the instructable for how to make topographic lines from images is here), but I wanted to use topography of real places. I'd tried several ways of doing this, first by getting topo maps online and trying to increase the contrast of the image and then trace the lines in Illustrator. This resulted in poor line quality, however. I'd also tried to use the USGS website to get files to then import into 3DEM, but I encountered a whole mess of problems. For some of the places I needed, I couldn't download GEOTiff files with which 3DEM works best, and one attempt to download GEOTiff files for a single place resulted in USGS emailing me 63 different files. After much searching, and hours of trial-and-error, I finally came up with a different, simpler method. With this method, using only SketchUP and Rhino, you can very easily create contours of any geography you wish, and etch or mill them on separate pieces of material so that when stacked, they create a 3D topographical landscape.
Step 1: Using SketchUp to Get Your Geography
When satisfied with the size of your 3D model, from 'File' and 'Export,' select '3D Model.' (Image 5) This will export your 3D model as an .obj file, which you can open in whatever program you like.
Step 2: Scaling and Orienting Your Object
Open your file in Rhino, and click 'Okay' in the .obj Import Properties window (Images 1 and 2).
Your geography is now imported! (Image 3) For this example, I used Long's Peak in Colorado. (This was one of the places I used for my final pieces.) First, rotate the object so that it is flat on your C Plane (rotate 90 degrees to the left in your 'right' viewport.) It is going to be an immense size, and you'll need to scale it, unless you'd like an object several hundred feet tall. Through much trial, error, and frustration, I figured out that the easiest way to do this is to move the lower left corner of your object to 0,0,0 (Image 4) and then scale from the origin point of 0,0,0. This way, no matter how much you scale your image, you will not lose your origin, grid, or object. If you somehow lose your model, right click on the viewport name, select 'pan zoom and rotate' and click 'zoom to selected.' Of course, this only works if your model is currently selected.
Step 3: Making Contours and Laying Out for the Laser
Once your model is the desired size, you can start the process of contouring and laying everything out for etching and cutting.
Create two points, one at the top left of your model and the other at the bottom right, and use those points to create a rectangle, that acts as a bounding box. This box will be the size of each acrylic piece. (Points visible in Image 1) Center your landscape accordingly. In Image 1, I have not yet moved my landscape so that the bottom is at Z 0.
Use the contour command, and set the distance between contours as the thickness of the acrylic. Depending on how many lines you want, you may have to re-size your model accordingly. Don't project any lines to the C Plane yet, just move the reference 3D model out of the way. Select the bottom layer of contours (I've found that it is easiest to use the box select tool, so that you make sure to select the entire layer) and group it with the bounding box (Image 2). Move the group to the side, make another bounding box, and repeat the process until each contour layer has its own bounding box (Image 3). Then, project everything to the C Plane, while in the top viewport.
When I made my own acrylic pieces, I wasn't positive that there would exist a glue or cement that I would like visually, so I decided to use brass-plated nails in the corners of the acrylic to keep them together. In Rhino, I created circles that the laser would cut out so the nails could be fitted in easily. To do this, I grouped contour layers and bounding boxes together, but didn't move them apart yet. For the Long's Peak acrylic, I made the bounding boxes 4"x4". The nails had a diameter of 0.098". I wanted the hole to be 0.2" away from the edges. It was then some simple math - making points at (0.2,4.8), (0.2,0.2), (4.8,4.8), and (4.8,0.2), then creating circles with a radius of 0.049 at those points (Image 4). Each group was assigned a set of corner circles, and the whole group was moved and projected to the C Plane. The groups were snapped together and arranged to be cut out on the laser cutter (Image 5).
Step 4: Stacking Acrylic and Assembling
The acrylic was cut out on one of the Tech Shop's Epilog laser cutters, and painstakingly separated. With the Epilog lasers, if a line is assigned a width of 0.01, the machine knows to cut it instead of etch. Therefore, the bounding boxes and circles were all assigned this width, while the inner topo lines were roughly 3pt lines. After cutting and etching, I decided that the etched lines would not be visible enough with the hair included, so I decided to use black India ink and a pen to make the lines darker. (In the background left of Image 1, you can see Long's Peak stacked without any ink.)
After rubbing and drawing ink into the lines, I added hair and squirted some acrylic cement onto it. If hair was rubbed against the ink, it would completely dissolve the ink, so I had to be very careful while rubbing the acrylic together to make the hair do interesting things. Because of the thickness of the hair, the acrylic cement did very little to stick the acrylic together, so the brass-plated nails were very important. I used some super glue in the holes to help everything hold together.
The finished pieces are shown in Image 3, and clockwise, they are:
Long's Peak, Rocky Mountain National Park, Colorado
Horsetooth Mountain, Fort Collins, Colorado
Sandia Crest, Albuquerque, New Mexico
Fifth Lake, Rocky Mountain National Park, Colorado