We set up a new welding station in the shop but the filters are constantly clogged. It works great and there's no residue in the air afterwards as long as there's a clean filter. We can usually tell by well the how the exhaust fan blowing or when we're done welding and its to late because the shop is filled with smoke. We going to use it sparingly from now on for rush jobs otherwise its being mothballed. Also we have been looking for a place to buy discount filters if anybody has suggestions.