choupi 10 oct 2013 :

I upload the *.obj and the *.mtl , then I edit the model, under my accunt,so it is not public but there is a 3dviewer !
I find the right adress, in the source code of the page :

escalier Domi :

iframe :also on sculpteo , btw :
iframe id="x3d-1407457-0" width="430" height="258" frameborder="0" style="overflow:hidden; border: 1px solid #dfddd9;"
so :

also on sculpteo , btw :

******reedit***** !!!!! WELL !!!!The right way is to upload VRML !! LOL

see :

"Add the VRML file (.wrl) and image file (.jpg or .png) to a Zip archive and upload it to Shapeways."

That works , I tried :