Vellum wire not wrapping right

[Adam Ferestad]

I am trying to play with the new Chain SOP and thought it might be cool to do some sims inspired by the example used in the release teaser and I am having some trouble getting Vellum to behave in an expected way.  I have a single curve being attached to a cylinder that is spinning on it's axis.  The wire should fall under gravity and wrap around the cylinder, but instead it wraps part way around, then holds its stiffness and just gets whipped around.  I have had it setup such that the rotation stops after 1.25 rotations and tries to let the rest of the wire drop down, but it just stands there, mostly erect, hanging off the cylinder.  Defying all gravity.  I have messed around at length with the bend stiffness, going so far as to set it to 0.  I have messed around with all of the bend settings.  The wire is also stretching by A LOT more than I want it to, but I have gotten some success with the stretch stiffness parameters seeming to work out correctly.  What am I missing?

 

[Alain2131]

Hi Adam
I don't know what you are missing, but I know for sure that we are missing a scene file to be of any help

I can only guess that the scale of your scene is too large. I noticed that Vellum isn't very good on large scales (a few tens of meters), and your wire seems to be like 30 meters long
Also, vellum likes to have a few substeps; the default of 1 is often not good enough. Try to put like 5 or 10, or even more (shouldn't have to go crazy with 50, something else is most likely the problem at this point)

Hope that helps !
Otherwise, as I said, please post a scene file !

Edited November 14, 2020 by Alain2131

[Alain2131]

Here's the most bare-bones setup for this

vellumWireAroundTube.hipnc