DUST COLLECTON 150MM (6 INCH) BELLMOUTH

The use of a bellmouth will improve dust collection from an open duct by an enormous margin, particularly fine dust particles.

This model has been designed to fit in a standard 6" (150mm) PVC plumbing joint and makes a bellmouth with an overall diameter of approximately 360mm .  The outer diameter is 154mm, the inner one 146mm.   It's possible to scale the size of course, but I would assemble a small slice from the inner opening first to check.

I have had a lot of success in printing shims and circular adapters in other dust collection fittings - so it is quite easy to be flexible if you need an odd size.

Print in six pieces, laid on one curved side - no support is necessary.  Assemble with cyanoacrylate (super glue).  There are no gluing tabs in the model, but the gluing surface is large and one side at least is flat from the build plate.

I've printed these in PLA and they have been in use for over a year at the time of writing without any hint of stress.

I have also inserted a wire mesh grill in the duct above the bellmouth to prevent larger offcuts, and personal items disappearing into the machine!