Three rack protectors have gone missing over the last few months, presumably being digested by the dishwasher’s grinder, so I ran off another batch:
I used the original solid model, shown here with the support structure outside for visibility:
I re-sliced the model to pick up whatever printer config tweakage happened since then. Those ribbed doodads snapped out easily and, in fact, some remained bonded to the platform:
No finishing required: just slide them over the pins atop a blob of acrylic caulk. Despite the few missing protectors, it does a good job of bonding them to the rack and sealing gaps in the worn vinyl coating.
I picked up a jar of ReRack glop on closeout duing my last pass through the Big Box Home Repair Store. It seemed a bit stiff, so I’ve added generous dollops of xylene, acetone, and MEK to thin it out; that’ll take a while to stabilize.