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This calculator determines the tensile strength needed by the bobstay for sailboats that have bowsprits. The theory is based on the law of sines. Since the headstay size is calculated by the need to hold the mast in place, which for the most part is directly related to the sail area, the size of the headstay is most generally provided in the plans. The calculator uses the breaking strength of the headstay to determine the maximum tensile load on the bobstay. The calculator also determines the compression on the bowsprit as a result of these headstay and bobstay vector forces.

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headstay angle with bowsprit
tensile strength of headstay (in lbs. do not use a comma)
bobstay angle with bowsprit


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