My experience... ferret piddle disolves all sealants,soaks into wood,corrodes metal.
Tried washing up bowls with side cut off,they poop on the outside of it! ...I once made a tray from an old road sign,difficult to make leakproof with pop rivets alone on corners and I can't weld.
i've salvaged a steel drawer from an old filing cabinet at work and cut off one end....
best so far but they still love to poop in the opposite corner of the cage!
One thing I will say (previously pointed out by Ditch).
If you feed your ferrets plenty of fur,feathers and bones,the poop is almost pleasant to hand