NX About the difference between the fillet weld construction method "Default" and "Roll Around".

What is the difference between the Fillet Weld construction method "Default" and "Roll Around"

The ‘Default’ option will make the decisions for either a normal weld, or a weld with a roll around condition, but can produce an incorrect solution if a roll around condition exists. The ‘Roll Around” option allows the user to positively state that the weld does have the roll around condition, so that when the internal code needs to decide it is “helped” with that decision from the user. If the user selects “Roll Around” and there is no roll around the condition, then, in essence, this will be ignored and the default (old) programming will be executed. So the recommendation is to use the “Roll Around” option when that condition exists.