I trying to modify a definition of an existing weld member feature. I had made an entire ANSI Pipe Library with almost all pipe sizes and thicknesses. Now I wanted to add the part to an assembly and modify the Size to what is needed for the particular configuration.
Please note that there is no API to change the size. Every size has its own file (prior to 2014 not sure how new weldments are now handled with API). So in order to change the size you need to pass the full path to a size profile.