No one uses lightweight fethering additive (west system) to fill in weave?

Interesting thing about cowls and wheel pants from ARF manuafactures, doesn't seem like they use ANY
epoxy, and the structure gets it's strength from some sort of heavy polyester primer or spray, (Alway white
This is then painted with color.

This can be seen anytime someone chips up there cowl or cracks up there plane..

Take a look next time you see one....You would be amazed at how these are put together...