Best way to capture V of start profile in sweep2


dead simple task…or so I hoped, looks simple enough !

file attached.

two rails and two profiles. One profile has a curve then straight line. I need that ‘bend’ captured in the resulting skin at that profile, feathering out slowly so its gone at 60% of the way to the curve profile.

Sweep2rail used.

Cyan as rails, dk blue as profiles, found that 40 entered for Cntrl Pts gave something looking better BUT upon close examination its rounded off that V bend.

try for the opposite, sweep B rails use as profiles and vice versa.

Now the crease is too prominent for the best part of the journey.

A is sort of there but I need a better V bend at the start.

Altering the control point value only sees isocurves increasing in one direction.

Sweep B is not how it should be, looking at the two, Sweep A is the best approach but kills the V.

I extracted isocurves (orange layer) to see if it was an illkusin but the one right next to the V bend shows a radiused bend.

I never find that the rails options are other than greyed out by the way, why is that ?

Skin sweep A capture of crease.3dm (120.2 KB)


Level II manual, page 91 (page 99 of the pdf)


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From Sweep2 Help (bold added):

Rail curve options

Continuity is only enabled if the rails are surface edges and the shape curves are non-rational, that is, all control point weights are 1. Exact arcs and ellipse segments are rational.

Another smooth curve is needed at the 60% location where you want the crease to vanish. You will have to decide what shape you want.