Construction fillet generated Fault

This is a retangular solid that’s been filleted with three different radi. The first is 10mm and then a second crossing the 10s is a varialble radius fillet. When extracting some surfaces to replace I discovered this little issue. It’s tiny, but it’s typically whats causing me grief. (852.2 KB)

The long edge of the top surface next to the fillet is out of parallel to the YZ plane by 0.003.

You probably won’t be able to find what is causing these errors or when they occur until you go back and very systematically re-create the geometry while checking every line and edge as soon as it is created or modified. As soon as an error appears make note of everything you did to create or modify that part of geometry and all OSnap and similar settings. Then back-up using Undo until all geometry is clean. Save it as a separate file. Proceed again creating or modifying geometry and see if the problem is repeatable. Once you have a repeatable problem let us know what occurred to cause the problem, and post the file without any additional modifications.

Any idea how your straight trim curves wind up with lots of control points?

you keep showing this model at 10,20,50 operations in… finding an error… then proclaiming the application is at fault since you’ve found an inaccuracy in the model.

i think less bandwidth would be used if you were to post step 1 of this file… say a rectangle… upload that along with an exact description of what you’ve done to achieve it… then let one of the more advanced users ok the procedure prior to moving on… then extrude the rectangle (or whatever)… upload… let someone check it… etc.

because ‘construction fillet generated fault’ is not actually at fault here… or, at least in the state of the model as uploaded in post 1, we’ve no way to determine if that’s a true statement… it’s likely the fault occurred prior to the fillet operation… finding this point would be beneficial in improving your technique.