AnsweredAssumed Answered

0.1mm press fit falls together under gravity

Question asked by Stephen Carson on May 22, 2019

I've got some plastic parts that require approx 50lbs to press into one another.

These take about 1 second to more than fully engage with one another.  Gravity is acting on the upper part, which weighs less than an ounce.

Hardware will draw these together, but that hardware is suppressed in my model currently.


I've tried FPS from 50-600

Low, high, and "Use Precise Contact"

Accuracy 0.01 - 0.00001

Gstiff & Wstiff solvers


I've tried contact types between these parts with and without friction

I currently have a custom material that 10x the impact damper, and reduces the penetration for that damper from 0.1mm to 0.01mm


The rest of my model is reasonable, but this interaction is not.  It seems as if slight penetration occurs, but then there are no forces present to push the two parts away from each other.  As the simulation continues it gets progressively worse until there is fairly large interference (+0.020").


I'm going to try to setup some light springs in the model to help this interaction, if there are any other suggestions I'm open to and thankful for them.