Calculate a recurve or longbow starting string length, or reverse-solve marked bow length, using an explicit AMO-style deduction.
AMO Bow String Starting-Length Method
A common starting convention subtracts a nominal amount from the marked traditional-bow length; the exact finished string must still achieve the manufacturer's brace-height range.
How the Calculation Works
For an algebraic solve mode, the selected target input is hidden, marked unavailable to assistive technology, disabled, cleared, and made non-required. Conditional workflows show only the values needed for that choice.
How to Use This Calculator
- Select the value or workflow you want in the Solve for menu.
- Enter only the visible source values and use the units shown beside them.
- Select Calculate and review the primary answer, supporting values, warning, and steps.
- Use Reset before starting a different bow, arrow, or round.
Worked Example
For a 68-inch recurve and the displayed 4-inch recurve starting deduction, the calculated string length is 64.00 inches.
Input and Result Guide
| Item | How to use it |
|---|---|
| Recurve | The calculator uses a 4-inch planning deduction. |
| Longbow | The calculator uses a 3-inch planning deduction. |
| Custom | Enter the exact deduction supplied by the bow or string maker. |
| Finished string | Confirm under the maker's tension and measurement convention. |
| Brace height | Tune only within the safe range for the actual bow and string material. |
Interpreting the Result
The result is a purchasing or build starting point. Small differences in construction, strand count, material, serving, and measurement tension affect the finished string.
Assumptions and Limitations
The nominal deductions are not universal manufacturing dimensions and do not apply to compound cables or strings. The bow maker's specification and achieved brace height control.
Common Questions
Why did a field disappear after I changed Solve for?
A hidden field is either the requested output or irrelevant to the selected workflow. Enter the remaining visible source values.
Will my last successful calculation be restored?
Yes. The calculator saves enabled source values and the successful result in this browser. Reset clears that saved state.
Sources
Archery Trade Association, AMO/ATA bow and string terminology; bow and string manufacturer specifications.