I am trying to create a groove concentric to a hole and failing miserably.

The hole is a steam passage. The groove is to take a compressible copper washer and is 2mm diameter offset so that the cut penetrates the body by just 0.9mm. The opposite part will have a similar groove, so there should the 0.2mm of crush when bolted together.

The hole c/l is coincident with the Front Plane, so I started sketching on that. There are two other holes to do so for them, I was going to create planes that bisected those holes. My plan was to draw a 2mm circle placed 7mm from the hole centre and 0.9mm above the face so when done as a revolved cut it would create a groove of 15mm diameter concentric to the hole penetrating the surface by 0.9mm.

Actually typing this has made me realise that this may be a lack of sketching knowledge as I can't get the sketch to pick the hole c/l of the face I need to cut into.

I'd be grateful for any pointer that creates the lightbulb moment that lets me proceed

To mitigate what perhaps ought to be blindingly obvious I am doing this whilst away from home driving steam engines on the Festiniog Railway on the hottest day I've experienced. Many things aren't working in the heat including my brain

Thanks in hope and anticipation

Paul Martin