Parts library
Cut a hole at the size the hardware actually is, instead of the size you remembered.
1
Pick what the hole is for: a bolt, a nut, a bearing, a motor, a board, a switch.
2
It uses the published figure. A 608 bearing is 22 mm, not about 22.
3
The hole is drawn smaller by your kerf, because the cut opens it back up to size.
Every setting
4What each number in the dialog means, and where it starts.
Part
What you are cutting the hole for.
Kerf
Your beam width. Holes are drawn smaller by this.
How many
Repeats the part in a row.
Spacing
Centre to centre, when there is more than one.
What it is
Drops in a hole or a hole pattern at the size the hardware actually is: bolt clearances, nut pockets, bearing seats, motor and board mounts, panel cutouts.