Find the flat-pattern length of a feature wrapped around a cylindrical part on a 4th axis, such as engraved text, a label area, or a helical groove span.
Wrap length = pi x diameter x (wrap angle / 360). At 360 degrees this is just the full circumference, smaller angles give the arc length for a partial wrap.
How it works
Anything designed flat, like a line of engraved text or a label graphic, needs to fit within the available arc length on the actual cylinder before it gets wrapped onto the part by the rotary axis. Converting diameter and wrap angle into a flat length lets you lay it out correctly before cutting.
FAQ
Does this account for the part tapering? No, this assumes a constant diameter across the wrapped feature. For a tapered part, use the diameter at the section you care about most.
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