...
Creating an identical job with the same forced blanks, but entering the above box measurements (A = 52.4, B = 37.2, ED = 54.8, ED = 18.0) without a trace and running the calculator gives a “Warning - both eyes will bottom out in block” message and smaller thickness values:
...
When box measurements are entered, RX-Universe has no way of knowing what shape is filling the box and thus will make an estimate based on the entered values. Take the example of these tracings:
...
All of these tracings will fit within the same box, however, each have different designs and will yield different edge thicknesses. Since RX-Universe has no way of knowing these shape, users can receive unexpected thickness values when using this method.
This can result in RX-Universe selecting incorrect blanks, especially blanks with a larger diameter. For the most accurate thickness measurements, it’s best to include a frame trace.