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.
Returns
Bought from clpa.au? You have 30 days after receiving your item to request a return. The item must be unused, in the condition you received it and in its original packaging. Email sales@clpa.au to start a return — items sent back without a return request cannot be accepted. Full details, including your rights under the Australian Consumer Law, are in our Refund Policy.
Bought on Amazon? Amazon’s return policy applies to your order.
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