What does the Flinders bar on a magnetic compass compensate for?
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Asked by: Ashley Lawrence
noun Navigation. a bar of soft iron, mounted vertically beneath a compass to compensate for vertical magnetic currents.
What does the Flinders bar on a magnetic compass corrects?
The Flinders bar is used to counteract the vertical magnetism inherent within a ship and is usually calibrated as part of the process known as swinging the compass, where deviations caused by this inherent magnetism are negated by the use of horizontal (or quadrantal) correctors.
Who invented the Flinders bar?
navigator Matthew Flinders
soft iron bar called the Flinders bar, which originated in recommendations made by the English navigator Matthew Flinders.
How does a binnacle work?
A binnacle is the housing for a ship’s compass. The idea behind a binnacle is to counter the magnetic deviation caused by the ship being made of iron so that the compass can point to magnetic north. Metals that were used to construct binnacles were required to be non-ferrous (containing no iron) such as brass.
Why is it important to provide correctors in compass?
Correctors may be permanent magnets or soft iron, which are placed adjacent to the compass. This creates equal, but opposing magnetic fields, thus nullifying the deviating fields around the compass, enabling it to align correctly.
What tool is used for compensating the compass in order to reduce the effect of the ship’s magnetism?
iron compensators
The deviation errors caused by magnetism in the ship’s structure are minimised by precisely positioning small magnets and iron compensators close to the compass. To compensate for the induced magnetization, two magnetically soft iron spheres are placed on side arms.
What is magnetic compass corrector?
Magnetic compass correctors in a binnacle
In the centre part of the lower half of the binnacle are contained many holes which contain inside them corrector magnets to negate disturbing effects of magnetism caused by the hull of the ship.
How many corrector magnets are installed in the binnacle of a compass?
two
There are two soft iron spheres carried on brackets fitted on port & starboard side of the binnacle. These are called quadrantal correctors. They can be moved on slots on the brackets and fixed at a specified distance during compass adjustment.
What is deviation in navigation?
Deviation is the amount by which the ship’s compass is affected by the characteristics of the vessel (such as the engine block and wiring / other ferrous metal objects, etc).
What is vertical soft iron?
Ship’s Induced Magnetism
Horizontal Soft Iron is induced by H component of the Total Force. The strength of Induced magnetism depends on the heading of the Ship. Vertical Soft Iron is induced by Z-Component of the Total force. The position of the poles will depend on upon the hemisphere the vessel is in presently.
How do you compensate a compass?
Compensating a compass consists in adjusting the position of the 2 magnets, in order to affect the horizontal component of the card by modifying the North/South and East/West deviation. Use a second compass as the reference ; a handbearing compass is often the most convenient, provided it is interference-free.
Why spare magnetic compass kept upside down?
The spare compass should be stowed upside down to avoid damage from pounding etc. Spare correcting magnets should be stowed a metre from the other spare compass parts and the spare compass.
What are the parts of a magnetic compass?
The basic parts of a magnetic compass are the needle (a thin piece of magnetic metal), the dial (a circular card printed with directions), and the housing (which holds the other parts in place). Inexpensive compasses, generally used as toys, may have no other parts.
What is the pointer on a compass called?
The magnetic compass is the most familiar compass type. It functions as a pointer to “magnetic north”, the local magnetic meridian, because the magnetized needle at its heart aligns itself with the horizontal component of the Earth’s magnetic field.
What do you call the four basic parts on a compass?
The housing is marked with the four cardinal points of north, east, south, and west and further divided into 2 degree graduations indicating the full 360 degrees of a circle.
