AutoCAD Inventor :: When Detailing Generated Frame View Shows Elongated Frame Members

I come across this problem from time to time and generally either just ignore it, if the detail is destined for in house manufacture, or alter it in autocad if it's destined for exterior suppliers.

Our guard frames are manufactured from extruded aluminum section (made by a company called palletti) I have when needed created a new frame generator frame member for each new x-section that we wish to use. I then draw a 2d sketch for the base frame skeleton and then a 3d sketch for all the frame work above. This I then use in an assembly to create the framework.  This framework assembly then goes into a second assembly where the framework is then adorned with all the accoutrements that make up a guard frame that we can then order as an assembled frame, panels feet, hinges et al.

When placing the views for the detailing of the second assembly sometimes the view will show the wrong length for one or some of the frame members.

;note how the left and right views are different and how some of the frame members are elongated on the lh view.

 I'm guessing its because of the home grown frame members but all seems to work well other wise and this only happens infrequently.

HP z210 16Gb ATI FirePro5800
Autodesk Produst design Suite 2012