This bar was created to insulate the following curing box:
http://www.appropedia.org/Curing_box_for_photocrosslinkable_resins
Insulating weather strip can be attached on the bar to insulate a box. The model is parametric and can therefore be modified to suit your needs by modifying the OpenSCAD script.
You might have to cut the model into two parts to be able to print it.