This partial calculator keeps only selected rotation and dimension arithmetic. It does not predict Spanish-windlass tension, shortening, damage or safety.
Partial · Selected Rotation and Dimension Ledger
Compare selected lever travel, rotations and rope cross-section without inventing a force law.
Equation Used
- Inputs are selected nominal dimensions.
- No constitutive rope behavior is inferred.
- Force, friction, shortening, damage, retention and safety are excluded.
The figure is a dimension ledger, not a tension or lock-off model.
Supported selected-value arithmetic
For selected lever length L, rotation count n and rope diameter d, the lever-tip circle is 2 pi L, total selected handle path is 2 pi L n, selected rotation is 360 n and nominal rope cross-section is pi d squared over 4.
These identities do not relate handle travel to rope tension.
Use and boundary
Use this ledger to compare selected dimensions and rotations only. Tension requires the initial loop geometry, operator torque, rope construction, stiffness, friction and lock-off method.
Dimension identities
C=2 pi L; path=Cn; rotation=360n; area=pi d squared/4.
Default selected-value example
For L=600 mm, n=5 and d=10 mm, the lever-tip circle is about 3769.9 mm, selected handle path is 18849.6 mm, rotation is 1800 degrees and rope area is 78.54 square millimetres.
Unsupported force and risk claims removed
The former 3000 N calibration, linear turn scaling, inverse-diameter factor and fixed eight-turn risk threshold were not source-supported and are not used.
Questions
Does this calculate pull?
No.
Does the turn count establish a safe limit?
No.
References
References & Further Reading
- Wikipedia contributors. Spanish windlass. Wikipedia
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