Opel Vectra head resurfacing

My tool was loose on the first pass which made the tool bite a little.
This head had a small scratch under the steel seal ring. I wonder why.
Using a reground Sandvik insert. I used around 0,2mm/rpm for roughing and 0,13 for finishing. Alcohol for coolant.

Видео Opel Vectra head resurfacing канала sunppaa