Jacob Ellis

Jim and Ushnish,

Thanks for your suggestions. SBOPT=5, DEPTH=55 with SOFT=2 had the same results. I have been trying to tweak the contact thickness and stiffness with no luck.

Do I need to tweak both SFSA and SFSB if it's *AUTOMATIC_SINGLE_SURFACE or just SFSB?  Same question for SAST and SBST. 

What range of values for SFSA/SFSB should I try first? And what percent of the shell thickness should I increase the contact thickness. I don't have a good feeling for what is reasonable and nothing I try seems to be working.