Problems starting a new route. It's stocked on a nominal size.

Hi,

I have a problems since a few days. I'm kinda new using routing/pinping add-in in SW (Using SW2020 SP4 By the Way).

I started a project using a nominal size o1.5 Schd 40 with slip on flanges but somehow in some point, the software took a behaviour a little strange or complicated.

Let me explain you: I started a new route in my top assembly model by dragging and placing a "SlipOn Flange #300 4inches" but instead of automatic selecting 4 inches pipe (Schd 40 or 80), software only gave me the option of 3.5" and I don't know why!

Thanks in advanced for any help

SolidworksRouting