Thanks Rob

Food for thought....
Blades are tightend to victa specs....and the disc has clearence for the blades to come in if hits any thing. The blades were "NAVY" tight before..
I'll keep an eye out for a 4 blade unit. I had an old Pope rotary valve mower which could just about pull worms out from 12" away

It had a great vacuum action and four blades, but the secret was in the blade carrier.....