I noticed that the performance of my woodshop dust collection system has been gradually declining over recent weeks. I figured it was time for some filter maintenance. I was shocked by the amount of dust that had accumulated within the fabric folds of the filter media. I estimate the pile of dust could easily fill a pair of 2-liter soda bottles. Predictably, when I returned the cleaned filter to service the dust collection performance was back to peak levels. Going forward, I think more frequent filter maintenance will be warranted.