Golden Ratio Ruler and No-Math Ruler Guide — Halves, Thirds and Fibonacci Without Maths
Dual-scale rulers that divide any length into halves, thirds or Fibonacci proportions without arithmetic. Scale A is a normal inch ruler. Scale B does the maths for you.
Quick Fixes — Read This Before Returning
- “Scale B doesn’t match inches.” It isn’t meant to. Scale B is a proportional scale — it shows where to divide, not a measurement. Use Scale A for measuring.
- “It bends.” That is the PETG. It flexes so it can follow curved work. Hold it flat for straight lines.
- “I got the Fibonacci ruler but wanted thirds.” Check the SKU list below — each ruler does one job. The Set includes all three 12" rulers.
Which Ruler Do I Have?
| Ruler | Scale B divides a length into… |
|---|---|
| DR02 — 12" Rule of Thirds | equal thirds |
| DR07 — 12" Halving and Doubling | halves — finds the centre of any distance |
| DR03 — 12" Fibonacci | Fibonacci proportions (1, 1, 2, 3, 5, 8, 13) |
| DR08 — 24" Fibonacci | Fibonacci proportions, for wider work |
| DR-SET-Rulers | all three 12" rulers |
How To Use Scale B
Scale B is Scale A compressed into a proportion. You measure on Scale A, then find the same number on Scale B — that point is your division. No arithmetic.
Finding a centre (DR07 Halving and Doubling ruler)
On DR07, Scale B is Scale A compressed by exactly 50%.
- Measure the full length on Scale A — say 9¾".
- Keeping zero at the same end, find 9¾ on Scale B.
- Mark there. That is the exact centre, 4⅞" from the end.
- Doubling: work the other way — find a length on Scale B, and the same number on Scale A is twice that length.
Thirds and Fibonacci rulers (DR02, DR03, DR08)
These work the same way: zero at one end, measure on Scale A, then read the matching divisions on Scale B and mark them.
Looking After Your Rulers
- Clear PETG, UV-printed. Clean with isopropyl alcohol or methylated spirits; no acetone.
- Store flat. PETG softens above about 70°C (160°F) — keep it off irons, heat guns and hot dashboards.
- Do not use as a straightedge for a craft knife — the blade will shave the edge.
Drawing shapes rather than dividing lengths? See the Fibonacci Drawing Templates support page.
When to Email Us
Email sales@clpa.au with your order number and a photo if your tool arrives damaged, you ordered the wrong size, or a printed line looks off-register. We aim to reply within one Brisbane business day — if you are in the USA or UK, remember we are a day ahead. We make every tool in-house, so we can usually replace, exchange or quote a custom size faster than a return would take.
Returns and Warranty
Unused items can be returned within 30 days of delivery in original condition — see our Refund Policy. Every CLPA tool carries a 12-month manufacturer warranty against defects in materials and workmanship. Bought on Amazon? Amazon’s return policy applies to your order, and our warranty still covers the tool.
More help: Frequently Asked Questions.
We Make What We Sell
Custom Laser Products Australia (CLPA) is a small veteran-owned family business. We design, laser-cut and UV-print every tool on the Sunshine Coast, Queensland. We are the manufacturer, not a reseller.
CLPA Customer Support · sales@clpa.au · clpa.au