There are chinese factories that do list making knotted skin pieces with front 1/8'' as v-looped on 0.08 mm (3 mil) skin throughout.

The only people I have seen listing knotted skin bases are listing it on 0.08 mm bases.

I think 0.03-0.05 mm might be possible theoretically for knotting, but I expect it would be very fragile since the knots could just pull through (unlike v-loops where the whole loop would have to tear to come through).