Washers -- Any Size

Here is a .scad file to make washers of whatever size you need. There are three variables at the top (outer and inner diameter, and thickness) change them to suit your needs (values are in millimeters). F5 to preview, F6 to render. After they are rendered you can export to STL.

Printed at 100% infill the washers are surprisingly strong (PLA). The included STL is an example that prints a washer with 30 mm outer diameter, 16 mm inner diameter, and 2.65 mm thickness. These particular washers are replacement washers that go behind some cotter pins that holds the mower deck on my Husqvarna riding mower. They appear to be up to the task (the cotter pins hold the mower deck on, the washers just sit behind the pins).

The picture is the printed washer next to the one metal original I still have.

http://www.openscad.org/downloads.html