Conical Lampshade Calculator

I’ve made this simple spreadsheet for working out the flat cutting pattern for conical and tapered lampshades. Enter your top ring, bottom ring and shade height, and it calculates the arc radii, sector angle and approximate material blank needed.

It’s intended as a practical workshop aid rather than a formal engineering drawing, so I recommend testing with paper or card before cutting final material.

While you’re here, I’ve also been developing Cued — a simple visual routine app that has transformed mornings in our neurodiverse household. It’s designed to help children move through routines with less stress, fewer reminders, and a clearer sense of time.

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