Maybe worth posting - Dust Bin Bag Holder Thingy.
My method to date for cyclone dust bin bag management has just been to keep an eye on it till enough spoil is in there to hold the bag well. With the DC out in a shed this would be problematic. Granted I am one of those that sometimes solves a problem no one has but, this has been planned for a couple of years. Finally . . .
Measure the circumference of your barrel. Add about 6" for overlap. Measure the depth. I left it about an inch short in case any bag material or spoil got trapped under it. Grab your FRP panel that has been patiently waiting in the garage since 2019. Cut your strip to size.

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Test fit, clamp to hold position and mark for rivet positions.
Grab that handy pop rivet kit you can't remember why you bought but use at least once a decade. This one is from Sears back when you could walk in, buy a discount tool, and expect it to work for awhile.
I chose to use a washer on the inside of the rivet to provide more grip on the fiberglass panel.
Drill a hole, push the rivet through, place the washer over it and cycle the tool.

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. . . cont'd