Intro: How to Make a Laser Cut Map of San Francisco
As an intern at Autodesk this summer, I am lucky enough to be stationed at Pier 9 with the Project Ignite team. I have full access to the all of the incredible machinery and resources of the Pier — in short, this place is paradise.
With my girlfriend's birthday coming up, I figured I'd make her something. She's from San Francisco so I thought I'd go with something SF themed. I had seen laser cut maps on the internet and figured I could make something similar.
You can download the Adobe Illustrator file I used as well.
Step 1: Quick Materials Check
For this map I wanted to laser cut an outline of all of the neighborhoods in San Francisco out of wood. I would then laser cut acrylic and use it as inlay for the wood. You only need a few things for this project;
Super glue (optional)
a laser cutter (I used a 75 watt epilog laser cutter)
Step 2: Making the Map
First things first, you need to make the map. I did a quick Google search for a neighborhood map of San Francisco which lead me to the map above. I put the picture into Illustrator and drew the map by hand. I had tried the image trace tool, but it wouldn't outline what I needed.
For the typography enthusiasts (and everyone else I guess), I used Optima for all of the neighborhood names. I am a sucker for sans serif typefaces. I had initially used Futura, but the computer where I was printing this file from did not have Futura.
Step 3: Designing the Poster
I wanted the final product to kind of be like a poster. I added the San Francisco text beneath the map and a silhouette of the Golden Gate Bridge.
Step 4: Testing
Before I made the final product, I needed to do some testing first to determine the settings I would use on the laser cutter.
I needed to;
- Determine the speed and power settings to cut the wood and acrylic
- Determine the speed and power settings to do the raster designs on the wood and acrylic
- Determine the percent scale needed to press fit the acrylic into the wood since some acrylic will melt from the laser
After testing I found the following settings to be best;
- wood (12/77/500)
- acrylic (8/90/5000)
- wood (55/90 with two passes followed by sanding to remove burn marks)
- acrylic (45/90)
When I was testing the percent scale of the acrylic, a colleague saw my project and recommended I mirror my image as well since the laser cuts at a very slight angle. The thought was that that way the angles would match up on the wood and acrylic.
The press fit worked better when I mirrored the image and I found a uniform 101% scale worked best.
Step 5: Things to Look Out For
When I was going through this project I ran into a couple issues.
- Is your wood bowed? My piece of plywood was a little bowed because of its initial size (24"x36"). This caused several issues when cutting the wood on the laser cutter. As the laser would go about its business, it would be in focus in some areas and out of focus in others. This would cause pieces to not get fully cut out, and doing another pass would widen the laser kerf which would cause problems when press fitting the acrylic later. I ended up cutting the wood down to 18"x24", pausing the job at different points and re-focusing the laser each time, and putting weights on the wood to flatten it.
- The press fit is not an exact science. In my testing, I found a 101% scale worked really well. However when I made the final project, this percentage only worked sometimes. I found myself cutting and re-cutting several pieces until they fit.
- Don't take the paper off your acrylic until the very end! Once I had gotten all of the pieces to fit, I tested the press fit by pushing on every neighborhood. For the pieces that wiggled a little bit I lined the edges with super glue which worked really well. Unfortunately I had taken the protective paper off a couple of the pieces and got super glue on the acrylic — not pretty.