I want to add my Thank You and express my gratitude to Phil for his giving so freely to us all his time and details of his design. I am sure that those of us that incorporate this device in our defense against the ravages of damage to our systems by fine particulate matter will indeed have a much better life and enjoy our wood working a lot longer.
I have shared this site with my fellow members at the International Association of Pen Makers - the IAP - and with many other wood working folks that I associate with.
Again ... Thank You, J. Phil Thien!