I have a couple of these Woodriver blast gates in my shop:

https://www.woodcraft.com/products/2-1-2-abs-blast-gate

They tend to get clogged in the back corners such that they don't close
completely. More often than I'd like I have to get out the air hose and
blast the dust out of the innards to get them to seal. Once they are clean
they work great...for a while.

Is this common with blast gates or are there better ones that don't clog?
I need 2 1/2" gates.

Thanks!