Parametric Washer Spacer Generator | M3~M12

Generate the exact washer you need — Flat, Countersunk, Shoulder, or Star-External — with a simple Customizer-driven model.

I’ve already used this generator to produce reliable M3–M12 washers, but it’s designed so you can dial in custom dimensions for special cases: odd hole sizes, non-standard outer diameters, thicker spacers, custom shoulders, or a star washer that bites on one side while staying flat on the other.

Washer types included

• Flat washer – standard spacer/pressure spreader
• Countersunk washer – for flat-head screws (choose angle + top diameter)
• Shoulder washer – flange + raised sleeve/bushing in one part
• Star-External – teeth on one side for grip, flat on the other (optional flip)

How to use

1. Pick a washer type in the dropdown.
2. Enter your hole diameter.
3. Adjust only the few parameters under that washer’s section (OD / thickness, etc.).
4. Export STL and print.

Printing notes

• Prints cleanly on most FDM printers; no supports in typical configurations.
• For countersunk/star variants, there’s a built-in option/behavior to flip so the “nice” face can be on the bed (depending on your preference).
• If you want a snug fit on bolts, consider adding a little clearance to the hole diameter (printer/material dependent).

Use cases
Spacers, shims, load spreading, panel mounting, custom bushings, anti-loosening grip washers, prototyping hardware when you don’t have the exact size on hand.