jrmelanson
With standard 142mm TA we are using the traditional 135mm spacing for the distance between the dropout inner surfaces as our design reference. What about Boost 148mm spacing, do I use 141mm (135 +7) or do I use the full 148?
TA Boost spacing
If you are working exclusively within BikeCAD, it is entirely up to you how you interpret the crude representation of the dropout that is shown in the auxiliary view. In the auxiliary view, each dropout is represented by a rectangle. The inner faces of those rectangles could be set to 148mm apart or to 141mm apart, depending on which surface of the dropout you are choosing to represent for your own purposes. It is only when using the Export to FreeCAD option that we have to standardize what these numbers are referring to. For reasons discussed here, you'll want to set the rear dropout spacing to 141mm for Boost.