# lifting the mast....how much force?

Discussion in 'Sailboats' started by centerline, Apr 1, 2012.

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### centerlineNew Member

I am in the process of designing a mast raising system for my sailboat.

the total mast weight is 50lbs with the rigging.... that is the weight of it balanced in the middle. it is 24 ft long. the bottom is anchored and hinged at the tabernacle and I would like to know how much lifting force will be required to raise it by lifting it at a point 8ft from the tabernacle.
this would fall under the catagory of a 3rd class lever, and all the formulas I have found to calculate it is all in code letters and symbols that I dont understand.
all I need is the actual weight to get it to move upwards as I know as the mast becomes more verticle, the force required will diminish.. thank you....

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### DCockeySenior Member

50 lbs x 12 ft / 8 ft = 75 lbs

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3. ### Submarine TomPrevious Member

Minimum 75 pounds as this is just equilibrium. To move it you'll need a bit more, but not much accept for mechanical loses...

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### centerlineNew Member

thank you..... that is what my simple calculations came to also, but I cant afford to be wrong.

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### PARYacht Designer/Builder

Build a cantilevered tabernacle and place a weight on the lower portion of the mast. You can raise it with your finger tip. Once up, remove the weight.

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### waikikinSenior Member

Weight a Moment...................... Apologies

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### JetboySenior Member

Are you planning to lift vertically? Or pull with a cable toward a winch of some sort?

8. ### Submarine TomPrevious Member

Booooooooo.

Pretty funny there big guy.

9. ### Submarine TomPrevious Member

Ah yes, vectors.

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### centerlineNew Member

I plan to use a 7 ft gin pole and pull up and slightly forward. the distance between the gin pole and the mast (the angle) will never change. it will be approximately 6ft between them at the attachment points. the gin pole is hinged at the tabernacle as well as the mast
the bridal from the gin pole will be attached to the mast at 8ft from the anchor/tabernacle.
the hoisting line from the top of the gin pole going forward to its anchor point is 5ft forward from the base of the gin pole......
the initial force needed to raise the mast will be greater on the hoisting line than it will be on the holding line between the gin pole and the mast. although I dont know how to calculate the forces I will create with this, I do know a little about geometry, LOL.... all the forces will progressivly lessen at the mast becomes more verticle.

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