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Parallel Rule - Captain Fields 12"

Name: Parallel Rule - Captain Fields 12"
Brand: Boat Books
Price: 44.95 AUD
Availability: InStock
Rating: 5 (2 reviews)

$44.95

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Parallel Rule — Captain Fields 12″

Essential Chartwork Tool • Precision by Weems & Plath

A dependable set of parallel rules is a cornerstone of traditional navigation—and an essential backup when electronic systems fail. The Captain Fields 12″ Parallel Rule is engineered for accurate, repeatable chartwork, offering the balance, rigidity, and clear markings navigators rely on for plotting courses and transferring bearings with confidence.

Built to Weems & Plath’s standards for marine instruments, this rule is equally suited to daily chart table use or inclusion in a contingency navigation kit.

🧭 Why Navigators Rely on It

Consistent accuracy — maintain true parallels while “walking” bearings across a chart
Confidence without electronics — dependable manual plotting when GPS or power is unavailable
Practical size — 12″ length handles most chart formats without excess bulk
Built to last — durable aluminium construction for life at sea

⚙️ Construction & Features

📏 12″ (305 mm) working length — ideal for routine passage planning and fixes
🛠️ Brushed aluminium arms — lightweight, rigid, and corrosion resistant
✋ Polished aluminium handle — smooth control and precise placement
🔺 Precision-milled, bevelled edges — clean alignment against chart lines
📐 Integrated protractor scale — quick reference for checking bearings and angles

The smooth action and stable geometry make repeated transfers accurate and fatigue-free.

📐 Specifications

Specification	Details
Length	12″ (305 mm)
Thickness	6 mm (1/4″)
Material	Aluminium (arms & handle)
Edge Profile	Precision-milled, bevelled
Scale	Integrated protractor
Weight	154 g (0.34 lb)

🎯 Ideal For

⛵ Sailors & offshore cruisers — essential backup navigation tool
🧭 Navigation students & instructors — clear, reliable chartwork practice
📚 Passage planning & coastal plotting
🧰 Emergency navigation kits — lightweight, dependable, no power required

The Captain Fields 12″ Parallel Rule delivers straightforward precision—nothing more, nothing less. Accurate, durable, and ready when you need it most.

Add a trusted manual plotting tool to your chart table and navigate with confidence.

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Frequently Asked Questions

What is the Parallel Rule - Captain Fields 12" used for?

This chart plotting instrument is used in marine and aerial navigation for measuring distances, plotting positions, and calculating bearings on nautical and aeronautical charts. It is an essential tool for accurate manual chart work.

Is this instrument compatible with standard nautical charts?

Yes, this instrument is designed for use with standard nautical charts. Check that the scale markings correspond to the chart scale you are working with for accurate measurements and bearings.

Is this instrument suitable for recreational or professional use?

Chart plotting instruments from Mapworld suit both recreational sailors and professional navigators. They are accurate, durable tools built for regular chart work in marine and aviation navigation.

Does Mapworld ship the Parallel Rule - Captain Fields 12" across Australia?

Yes, Mapworld ships Australia-wide. Standard shipping is a flat $7 rate, with free standard shipping on orders over $75. Express options are available at checkout. Most orders placed before 2pm AEST on business days are dispatched the same day.