Ruler Caliper - WESTCOTT Ruler - Helmet Sizing Tool

Designed to slide over a WESTCOTT ruler 30mm wide, either 12 inch or 15 inch length. Will install to measure Metric or flip around for Freedom Units.

A test section is provided for print calibration check. This 3d Model is designed to exact real life measurements.

HELMET SIZING
Arms are 100 mm length to accommodate measuring your giant head. Download and open the HEAD model in your slicer program and size it to your head measurements. Load your helmet into the slicer and virtually adjust the size around your severed head. LOL

HEAD
https://www.thingiverse.com/thing:979818

Printing
Supports - #$%& NO!
Layer Height - Your call.
Rafts or Brim - You better not!

I designed it to be printed at .32 layer height. The bottom two layers have a relief that will eliminate any elephant foot.

2/11/26 - Smaller Jaw version available here:
https://www.thingiverse.com/thing:7293368

ADDITIONS
-Slider that has a 8M Corse Thread 1.25 Bolt Hole
-8M Corse Thread 1.25 Bolt

2/11/2026 - Added a couple chamfers needed to for the jaw and readout edges.