I trouble importing a 3D model (that I created in Blender) into Tinkercad. The model is made out of quads (and definitely has to), therefore, I have to import a OBJ file instead of a STL file (the STL file triangulates everything). The problem is that it seems to be impossible to download the OBJ file. When I do so, no new objects appear on the workspace. The preview of the file is perfectly fine, so that is not the problem. See the pictures below. I hope someone can help me (with un-triangulate a STL file or a correct import of the OBJ file).
ABOVE IS THE BLENDER DESIGN
ABOVE IS THE STL VERSION IN TINKERCAD: WITH THE TRIANGLES I DON'T WANT
SEE ABOVE: THIS IS THE CORRECT PREVIEW
SEE ABOVE: THIS IS NOT RIGHT: 0 MB -> IMPORT -> NOTHING...