Hollow object printed as a solid

[Lorcoft]

Hi folks;

I've discovered a weird issue when printed hollow pieces. I was printing a new extruder fan duct and it seems to import fine but when I tell S3D to prep for a print, the stl is capped and shown as a solid object. It also subsequently printed as a solid object.

This happened when the stl was oriented upright. I rotated the same model horizontally and it sliced, printed fine.

I then tried to slice a flash hider for a DL-44 which is essentially just a cylinder. The same thing happened, it seemed to import it properly (I could look down onto the stl in S3D and see the grid), but when I prepped for print, it came up as a solid object.

I had 3 other pieces in with the flash hider including the upper rcvr for the DL-44 which has a lot of hollow space. They all sliced properly.

I don't use a raft and had minimal supports.

ideas?

~Lorcoft.

[airscapes]

Probably not your issue, but I accidentally had "Merge all outline into solid Model" clicked on the Advance tab and that is exactly what it did!

[Lorcoft]

Actually, that's exactly what I did.

I was pulling my hair out trying to figure out what was wrong with the model.

Thank you!!!