another trapped thing (Q45675)

Hello 3D-World! just another useless but somewhat interessting--if not pretty--thing to at least test your skeinforge bridge- and/or overhang-settings! the model was made with Inventor; I tried this with openscad but failed for the nice fillets around the middle square holes (which actually is only the press of a button in inventor). (I included the fillet-less openscad version, maybe you could do better) it's actually very well printable (see my photo) - but skeinforge behaves kind of strange w.r.t. the bridges over the inner holes (the left one failed completely on my print but nevertheless the final result is quite ok). the outer bridge strangely was done correctly... This is my first publication, hope you gonna enjoy it...