So, the canister filter was totally blocked off too. We took it outside, dumped the dust in the dumpster, tapped it to knock more off, sprayed with compressed air, over and over. The dust didn’t seem to end. The canister filter is somewhat diminished in that about 1-in-5 pleats has swollen wide open while 4/5 are pinched off. It’s a problem with all pleated filters, this isn’t really fixable by cleaning.
These filters are great on paper, but I think we’d get much better performance with trying the extra-large fine-particle shaker felt bag (like 1 micron). I’ve got one, we never installed it. While white and look like the stock shaker felt bag, they’re all different. Stock bags are usually 20 micron, which allows for minimal back pressure in a ~30" tall bag, but it lets through the super-fine dust that is a big concern. “PM2.5” and smaller (2.5 micron) is the most troubling health concern for dust, as it floats and is readily respirable deep into the lungs.
While they have minimal back pressure while new (or cleaned, while the pleats are still open), like any filter they will develop back pressure when loaded. Central problem here is the canister filters are a significant project to remove, clean, and reinstall and it’s a major affair you need some skill in.
So, bottom line, you CAN blame flow problems in the main dust collector on the filter. The clear bag on the cart should be limp while running. It’s often inflated with significant static pressure, sometimes tight as a drum, this is all back pressure from the filter and it inhibits CFM flow through the entire system.
The shaker felt bag, though, “cleans” fairly well by taking a heavy stick (like PVC pipe) and just beating the bag in place. Like it owes you money. It readily restores the filter with minimal work and skill, it is realistic to do this every day and get consistent performance. You don’t take anything apart and you don’t end up caked in dust. It’s kinda fun, too. The dust loading the filter will just fall down into the clear bag and there’s no other special work. Also, there are even solutions with auto-shakers that will self-clean a shaker filter.
I did see there was a time when someone tried to put a drop-in 1 micron or other fine bag on the central dust collector. That will not work, 1 micron bags are higher flow resistance per sq meter of surface area and that dust collector is modded for much higher flow than stock, even brand new that will create unacceptable back pressure and limit system flow. It will work great though, it just needs a much larger bag suspended from the ceiling like the CNC router uses. These tall bags really do perform well, the main reason they’re not used as often is they require a high bay ceiling to hang them, or an array of shorter bags in a baghouse. We’ve got the high bay so we have a very strong case for the tall bag. And, again, we already have one of the small-particle, huge ones on hand. Two different types, IIRC.