Ok so can I create a circle with a 301mm circumference and then map it to the polyline or maybe warp it to make it a similar shape? It doesn't have to be precisely the same shape only similar?
1. Select that line and the length will be displayed.
2. Scale the line to 0.9 and examine the length.
3. Then you can see the length when it is reduced by 10%. (36.577 shorter)
4. Change the scale back once with Ctrl+Z.
5. Based on the difference between 300 mm and the current line length, the Ratio Calculator can calculate what percentage of the line length has been scaled.
(365.753 - 300.00 = 65.753)
(0.1 : 36.577 = X : 65.753)
6. Scale down from that value.
7. Complete.
Oh, I made a mistake and set it to 300.
I think you can do it the same way with 310. Please try it.
Yep, thanks for that. A brilliant workaround. Took me a few moments to work out the ratio calculator and I still totally worked it out as the percentage was .05 out but I will work on that to suss it out properly. But it got me close enough to adjust by trial and error so I got my line length about right.