iTouchless Rectangular Trash Can Ring (Open Top)

After having several iTouchless rectangular automatic trash can lids fail just past any waranty, I decided to trash the lids and repurpose the cans. Two are in the workshop now holding various scraps of wood and tubing. One I converted into an open-top trash can with this... thing.

The original lid and retainer ring are not needed, as this fits right on top of the can on either side of the rim to keep the trash bag in place. The outer rim is deep enough to hide the edge of the trash bag, if it isn't pulled too far down over the top.There is a small pocket on the inside of the inner rim to allow for the welded seam on the back of the can, a bit wider than needed for my can, in case the seam on other cans is in a slightly different spot.

My QiDi Q2 could not print the whole thing in one go, so the ring is broken down into four pieces. To avoid adding more bulk, there are two slots at the ends of each ring piece, with small and large "biscuits" to hold them together. These can be just