Ventilation and control of dusts when grinding Finishing
The box, for 300 CFM, could be 10" wide and min. 8" long. The bottom of the box should be 8" below the transition and the divider stops 6" above the bottom. Lastly, let''s extend the box''s height above the transition by l" or 2" and ensure that you have a minimum straight run of ducting of at least 4 x dia. = 2 feet before the unit.