wall thickness

When you generate miter templates as described at: bikecad.ca/miter_templates, BikeCAD will prompt you for the wall thickness of the tubes. It does this, because the templates trace out the path of the miter for both the outer and inner surfaces of the tube. The profile of the miter on the inner surface of the tube will be dependant on the wall thickness of the tube. However, this is the only place where wall thickness is currently expressed in BikeCAD.

If you would like to document the wall thickness of the tube in your drawing, I would recommend doing so with an on-screen note as described at: bikecad.ca/adding_notes.