bathymetric /ba-thi-ˈme-trik/ of or relating to measurements of the depths of oceans or lakes
What's this all about? ...Here's an introduction to this blog and here's a 30-second overview of the book itself

Thursday, October 3, 2013

Bathymetric Book Meets Laser Cutter

I am now exploring options for creating my "production prototype," or an easily reproduced version of the book. I'm figuring out the tools, the materials, and the process that will ultimately create my edition. This summer, I expanded both my toolbox and my support network by joining a local makerspace/hackerspace called Sector67My monthly membership dues give me access to a wide variety of tools, including a laser cutter, along with the guidance of experienced users. 

Because the hand-cutting was the most time and labor-intensive aspect of the original, I worked to replace that step first... by creating a a laser-cut draft of the book. This draft makes two important modifications from the original version: 
  • It is machine-cut, instead of hand-cut, which dramatically reduces the time and effort required to cut the contours. 
  • It is laid out in folios, or folded sheets, instead of flat single sheets, which allows me to change the binding, letting the book's pages open more easily.  
To implement these changes, my proficiency in software came into play again. 

I took my original bathymetric contours and laid them out in a double-wide sheet with the normal contour shapes on the right side and their mirror image on the left. This allowed for the change in the binding structure. 
I exported consecutive pairs of contours to 
the file format that the laser cutter accepts, enabling the machine to do the cutting for me. I even included the edges of each sheet to be laser-cut, eliminating any precise alignment of the paper on my part.
Although it may seem very streamlined when I present my step-by-step procedure, real life wasn't quite so smooth. Even with excellent guidance from the Sector 67 staff, I was completely new at this, so mistakes were made. I exported these files many, many times (manually selecting the correct lines for each file again and again) before getting every setting right. 

Finally, my files were uploaded to the cutter. I hit 'Start' and watched the laser work. 

Each large sheet of drawing paper accommodated four double-wide pages for the book, each of which would be folded in half to form a folio. This time, I cut each large sheet separately and only created one copy, but the laser is capable of cutting multiple stacks of paper. I'm confident that I could lay out and cut 5 or more copies of the book in one laser pass. 

Before the sheets were folded, half of the contours 
appeared on the left and half on the right.  

After folding, the folios stack up:

I'm really happy with the results of the laser cutting test. It does char the edges of the paper, but I think my design could accommodate this effect.  The cutter executes the detail more precisely than I could ever do with my Exacto knife, and the intricacy is fascinating. 
After the files were ready, the cutting took minimal effort, AND most impressively, the cutting took only four minutes of laser-firing time! 

It's very exciting, as well as reassuring, to have this test run go so smoothly. 

Making it all possible, Sector 67 has been an invaluable resource for me. Chris, the founder of the organization, has been generous with his time and spot-on with his advice as I learn to use the laser cutter.  At the monthly meetings, I have found a welcoming audience; attendees have offered great questions, solutions, and publicity opportunities. 
I have certainly felt a boost being surrounded by the 'maker's attitude' within the group, helping me believe from the moment I walked in with my project that it can be done, and that the entire place exists for people like me with projects like mine. 


  1. This is wonderful. I have really enjoyed reading about your beautiful book. Are you willing to make the vector contours available for others to experiment with?

    1. That's possible, but you'd be limited to the contour interval that I chose...
      I suggest going straight to the source, the original data:

      You can download the DEM and open in QGIS (a free GIS program), then use the contour tool to create contours at any interval.