For what it’s worth , I’ll tell you how I did this. I cut the foam about a half inch wider than the filter cage so it fits in nice and snug against the edges, I also cut it long enough for the ends to overlap. Then instead of gluing it, I’ve got this green vinyl coated twist wire , that I picked up in the garden shop at the local home center, it comes on a roll, it’s cheap and used for tying plants up. Anyways, nobody sees this filter, I wrapped some of that wire around the foam in two places, just to hold it in place. Then when I want to clean it, it’s easy to undo the wires and just take the foam off to wash and re oil. Sorry no photos of the twist wire.
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