This is a crevice tool I created for my Ryobi Shop Vac.  I can only print 100mm high — so many of my models are 100mm.  But I created 200mm and 300mm long STL files.

Every part of the model is parameterized in OpenSCAD.  By changing the values at the beginning of the file, you can print a crevice tool for almost anything.  Got a VACTOR 3000 (truck that cleans sewers)?  Sure.  You'll just need a big 3D printer.

The noz_id is the inside diameter of the part or the outside diameter of the vacuum hose fitting you're using — the first thing to set — the Ryobi is about 31.5mm or so … so I chose 32mm.  This fits well.  If it's too tight, add half milimeter or so.  The total length will also set the size of the object you're printing.  You don't need supports if you print it upright, but you're limited by your print height.

crev_dia and crev_len set the size and distance between the round edges that form the crevice tool.  I made two each such that the vacuum end could be slightly larger — to make the laminar flow better.

Lastly, inter_len controls the length of tube that transitions between the round vacuum fitting and the crevice tool shaped section.