December 2020-Laser Engraving with A Graphing Calculator!

Have you ever needed a way to impress your math teacher with a unique work of art? Are you tired of doing your Calc homework, but still want a way to feel like you are doing math? Do you want to combine all this with your laser engraver? If so, read on!

What we will be making today.

If you're like myself, you've probably once gotten trapped in the endless rabbit hole of making designs with Desmos. This is a popular web-based graphing calculator that is (thankfully) replacing the Ti-Nspire as students' graphing calculator of choice. Compared to the Nspire, not only is Desmos free, but it is sleeker, faster, easier to use, and doesn't feel like it was coded during the same time when my dad was learning Fortran. Along with solving/visualizing equations Desmos can make a lot of cool, aesthetically pleasing designs out of equations:

A design for my Calc BC teacher, made out of equations.

Now, the cool part about designing with a graphing calculator is that every single line/curve/point you plot is represented in, well, a graph. This means that it is fundamentally similar to a vector image, which is the same type of image many laser engravers use (or can be easily converted into a type that works). See my last post if you are unsure about how this exactly works.

Indeed, a Desmos graph can be easily exported to a .svg file, a type that can be imported into Inkscape (a design software) for laser engraving. The documentation on how to do this is a bit shaky, so let's take a look at how I prepared a design for laser engraving a competition entry.

The prompt for the digital art competition was to design a "math sheep".

After designing your work in any web browser that works with Desmos, save it to your account, and open it in Firefox. While in Firefox, install the Greasemonkey extension. Once complete, press the Greasemonkey icon in the top right corner and click "new user script":

You should now be given a screen that looks like this:

Copy and paste this file into the unnamed script and press the save button on the upper left corner. Credit to baz1 on GitHub.

This should work!

Now, when you refresh Desmos, you should see a "Get SVG" button on the top left. Before pressing it to download your .svg, unselect the "Grid", "Arrows", "X-Axis", and "Y-Axis" buttons in settings.

When the .svg is downloaded, know that (with my setup) it WILL NOT AUTOMATICALLY BE RECOGNIZED BY THE COMPUTER AS A .SVG. You can fix this by renaming it as anything with ".svg" to the end of the file's name.

Renaming the file from the default u7skVC33 to u7skVC33.svg

With the bug fixed the file can now be opened with Inkscape:

We're in!

After resizing and a few additional modifications, you should be able to laser engrave what you designed with Desmos!

Some adjusting and engraving later... and it looks great!