"... thx, but not a speedy way."

Just to be clear, you changed your images after I replied. I was responding to the vertical slot and using boolean diff to create it.

If performing a simple boolean operation is not speedy enough, then I don't know what is.

To address your latest images:

I would have created the cylinder in MoI with the horizontal groove in a single operation using Revolve with a profile curve that included a notch for the groove.
Then create each vertical groove by extruding a rectangle and Boolean Diff with the cylinder.

Practice will make very speedy.

Ed Ferguson