Processing app to create guilloche-like images—similar to a spirograph—using three layers of repeating circles, with controls over each layer.
The app starts with a single layer. Adjust the sliders at the top-left to change different paramaters including size, thickness, number of repeats, and even rotation angle. The design will update in real-time with your changes. Setting a thickness value to 0 (zero) will turn off a layer, while any other value will turn on that layer.
After creating a design you like, you can export either a PNG or SVG of your design. You can use PNGs to raster engrave with a laser cutter, or the SVG to send to a CNC or pen-plotter (e.g.: AxiDraw)
To run this app you will need Processing (processing.org) and the ControlP5 library (Sketch->Import Library...->Add Library...)
Here are a few examples, including the interface:
NOTE: In-app images may go outside the bounds of the screen, but the saved PNGs and SVGs are NOT cut off! I wouldn't do that to you! :-)