I searched through the various dust collection attachments on the site and only find a few that peaked my interest so I am in the process of designing one myself. Here are the parts I have designed so far, all is currently for 1-3/4" currently as that is what I use.

v2: Added new versions, and M55 thread to attach hoses and make custom curves and attachments.

I haven't printed this yet, I am in the process of restocking some filament.

Print recommendation: Twb010 has printed a version with 0.8mm nozzle and 0.6mm layer height which resulted in some layering issues in the top half. After reviewing the issue and simulating some prints, with th angle of the spiral on the inside the top should be printed at less then a .35mm layer height. I am going to be printing a test this weekend using 0.2 or 0.3mm.

I printed out the top portion this weekend using a 0.8mm nozzle and .3mm layer height, my retraction settings were not optimized but other then that turned out well. Need to fine tune the inlet nozzle.

12-8-2017: Uploaded a new version of the bottom, removed the fins, thinned the walls slightly and expanded the base to add more room for fasteners.

12/18/2017: After printing V2 I added V3 that adds a little more clearance to fir the bottom to the top. Will be adding test videos soon!