Thanks for input appreciated here are a few tests I have carried out I created polyline with a vertical deviation of 0.7mm from which I could apply fillets and shell and the pipe software could still detect the bend info practically straight piece of pipe I have included a screenshot of the bend info. Once I put the curve deviation down to 0.6mm could no longer apply fillets which would back up the minimum 1 degree radius. In the reconstructed 3d polyline I have highlighted an out of range fillet node. Thanks for the info a getting a better idea of the limits to which I can push the pipe bending machine. I will play with applying 1 at a time rather then group application.

Hi Alex, so you can probably get the missing one by using Edit > Separate on the polyline and then selecting the 2 separate individual lines there as the input to Fillet.

When fillet is given 2 separate curves that's when there isn't an angle limit used.

The fillet piece will be very small though when the the lines get close to colinear.

- Michael

Thanks Michael - the information provided has been very insightful into the process of converting these 3d spline curves back into usable polylines for tube bending process and understanding the limits ill post some pictures of bent pipe once we begin just been sorting files.

All the best
Alex.