I used ABS and 0.2mm layers; this allows a light sanding to get an acceptable finish without waiting hours for the print to end. I have printed it in three separated parts : the bottom with the teeth, the top tube and the middle : - separating the teeth from the rest avoid sticking problems of the middle part, - the top tube can then be printed with an orientation that allows the best sturdiness. The cut was done using slic3r, then I merged the parts using acetone. Supports are not necessary if you do not care of the interior aspect. Once printed, I put a layer of acetone on all the nozzle to slightly help its solidity (especially the teeth).