Quick answer: Relate travel to the effective winding radius through the actual spool geometry. A fixed circumference estimate may fail when cable builds in layers.

How are cable travel and spring turns connected?
For a nearly constant radius, travel per turn is approximately the circumference. With multiple layers, the radius changes and the calculation must follow the build. Account for unused cable, attachment lengths and the spring's approved rotation window.

A practical verification method
Compare measured payout per revolution at the beginning and end of the intended cable travel.
| Item | What to record | Purpose |
|---|---|---|
| Reference configuration | Part or assembly identity and drawing revision | Make comparisons traceable |
| Test conditions | Relevant position, direction and operating condition | Compare the same characteristic |
| Decision evidence | Compare measured payout per revolution at the beginning and end of the intended cable travel. | Resolve the specific question before approval |

Use the result in an engineering request
Describe the observed condition and the required function separately. Include the relevant drawing revision and your results from the check above. If an acceptance limit has not been established, identify it as an open design input rather than treating a successful trial as approval.
Review the related Leading Spring product information. For a project-specific review, send the mechanism description, available geometry and the evidence relevant to this decision through the contact page.
Editorial note: AI-assisted engineering guidance, prepared from the topic-specific reasoning shown here and the company’s public product context. Illustrations explain decisions; they are not customer-case photographs or test results. Product-specific suitability requires review against your approved requirements.