Pure poser/UVMapper solution: Load object in Poser, selecting invert normals (or flip normals, whatever) Export object again Load inverted object in UVMapper Assign materials Load both in Poser Export both as a single OBJect. Of course, it will be two sided but will not have thickness. I get thickness in 3SDMax like so: Select object to make double-sided with thickness Clone it (from the edit menu so it doesn't move) Apply a Normal modifier with flip normals Select object that represents the side you want to thicken towards (i.e., if you have armour that you sculpted and want to thicken out from the surface, select the outward-normalled mesh/polymesh, which will be the original not the clone). Go to poly sub-object mode Select all polys Add a face extrude modifier and adjust thickness to taste without selecting or deselecting anything, hit 'detach'. This will seperate the vertexes at the 'edge' you just created so that the thickness will not try to smooth out. Caravaggio, you should be able to fix your problem by importing it to Poser (at least 4 anyway) and re-exporting it. Use 'Make polygon normals consistent' when you import. Of course, this will also reduce your OBJ float precision to 6 as per Poser's internal standard. If yuou use 8 or 10 this will be a reduction in vertex precision.