When you download honeycomb creator, it includes a pdf file of documentation which includes instructions for creating the t and 2t thickness.

But why would you do that in a 3D printer? That makes no sense.

What are E1, E2 and E3?  Are they the Young's Modulus for the two print head directions and the platen direction?

After you use honeycomb creator, you will have surface bodies. You will then create two facesheet surface bodies for the top and bottom faces and use Form New Part to combine them into a beam.