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Annapolis Compass  

Magnetic Compass adjusting in any weather by a Master with a Gyro System. The most accurate compass adjusting system available

Compass Heading Problems?

 -They Need to be Corrected-

Experts in both magnetic and flux-gate compasses. Over thirty years of experience in engineering, construction, maintenance and operation of sail and power, pleasure and commercial vessels. Wood, fiberglass and steel experience. Member ABYC, NFPA, International Maritime Institute and SOLA certified. Surveys, damage consultant and insurance claims. USCG / USN Approved.

We can help you with

Compass adjusting in any weather.

Compass Swing / Adjustments


Compass adjusting aims to nullify the effects

of the various magnetic fields by placing

corrector magnets adjacent to the compass

enabling it to align correctly.

Compass Repair

We will provide the proper repair / service

with one of our professional partner facilities. 

Expert service and master craftsmanship. 

Ritchie, Plastimo, Cessens Plath, Danforth, Lilly, White, Dirgo, Weems Plath, SUUNTO, ITT

USCG Deviation Tables

Deviation Table are a quick reference posted on the vessel's bridge / helm to show the amount of deviation for any heading. Over reliance on electronic navigation aids, gyro compasses, radar, GPS, DP, is not recommended.

In an age of Global Positioning Systems & Computer Navigation,

Who needs a Magnetic Compass?

Your old-fashioned mechanical magnetic compass is reliable, nearly failsafe backup every navigator needs to insure that if the power fails, the computer crashes, batteries die, the government switches off GPS, lightning strikes, or streams of ions from a solar flare disrupt satellite communications, you will not be lost or stranded.  GPS will give an indication of direction, but only if you are under way. The properly compensated magnetic compass is the most reliable source of heading information.

How about relying on an electronic or flux-gate compass as my magnetic compass? The new technology electronic magnetic compasses have many nifty convenience features. But they are still electronic devices subject to the same potential for failing when you need them most that are described above. You may want to have an electronic compass as a convenience just as you have a other electronic navigation aids, but you still need a reliable mechanical magnetic compass.

How Do I Go About Getting My Compass Adjusted?

There are professional mariners who man commercial ships, Navy and Coast Guard vessels who typically hire a professional compass adjuster rather than try to do it themselves. The skill and expert equipment of a professional adjuster will make your adjustment last and give you the piece of mind knowing the accuracy. For over 30 years Joseph L Duffy & Son (& now Grandson) has offered professional compass adjusting services in the Eastern-Atlantic for recreational, commercial and military vessels. Our staff adjusters have adjusted every type of vessel imaginable from top-secret military ships to trailer-able boats . Weather its a new vessel or one you had for years you should have an accurate compass for your mariner voyages. 

Please call for a consolation by clicking the contact or call 410.626.9892

Complete Magnetic Compass Correction Service

Does your ship's magnetic steering compass indicate correctly? Does it agree with the ship's heading data from other sources, such as GPS, autopilot heading systems, land ranges and chart plotting systems?

About US

30+ years as a Sailor, Compass Adjustor and Son of a Compass Adjustor give us a unique advantage and a special insight into the use, performance and practical problems associated with all types of magnetic compasses."

If you need help, please give us a call.

  • Give us a call 410-626-9892

  • What Our Clients Are Saying

    US Coast Card Recommend Compass Adjusted & Calibration Every Two Years.

    ''They Corrected the Heading and I feels a lot better operating the boat now, Thanks.''

    Jack R.

    Annapolis, Maryland

    ''We are compliant with our annual inspection. Thanks for the fast expert service.''

    Gerald W.

    USCG - Philadelphia Pa 

    ''Installation and calibration were perfect. My Plastimo. Great expertise and helped understand the process!''

    Thomas K.

    Commercial Tug & Towing 

    Call for information or schedule an appointment with us today!

  • Annapolis Compass, Annapolis Maryland USA

  • 410-626-9892

  • Questions-Consultations 

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    AnnapolisCpmpass.com©2023 -

    A REMINC Owned Company since 1984

    Ritchie, Plastimo, Cessens Plath, Danforth, Lilly, White.