This is a cyclone separator for a shop vac. I recommend printing with .3mm layer height and at least 3 shells. Thinner layers are not recommended. The walls on this print are probably quite a bit thicker than they need to be, but the end product is pretty robust. It took a little over 1.5kg of filament and around 24 hours to print on my Lulzbot.
I glued this together using black ABS pipe glue. The same stuff used for drainage pipes. Mine was old and really thick and unusable, but I mixed some acetone in it and mixed it until the abs glue was useable again. I applied it pretty liberally and then wiped away the squeeze out.
I had to do quite a bit of sanding on the bottom edge of the top half to get the pieces to fit together. If I was to make another revision I would probably allow for some clearance between the pieces.
The final finishing step I did was to sand the outside with 100 grit sandpaper knocking down some of the layers then spray the whole thing with Plasti Dip spray finish which is a fairly thick, rubbery finish. This was both for aesthetics and to help seal any potentially tiny gaps between layers. I don't really think this step is necessary considering how thick the walls are.
The base requires 3/8 bolts and washers. I attached it to a standard 5 gallon bucket with a piece of 1/4 MDF as a backer.
Designed using Fusion360. This was designed for and printed on a Lulzbot Taz 5 printer and may not work with smaller 3D printers.
Fusion part: http://a360.co/2mt6TKt