To start, create sketch on XY plane and create two circles, one on origin with diameter 60 and another with diameter 40, dimension contrain center to another center of 129
Next, extrude 2 circles with the direction use symmetric for easier design in later parts
(Origin point usually will align either at center point, or horizontal/vertical to origin point which ccan help better construction sketch in later parts)
After done, create a rectangular sketch, constraint with a width of 20 (constraint into center of circle or to the circumference)
Next, extude the rectangular sketch with direction using symmetric
After that, create a 6-sided polygon on diameter 60 circle and 5-sided polygon on diameter 40 circle
Extrude the polygons sketch, instead of join or new body, type of extrusion is cut
On the rectangle extrude part, create a slot with center to center diamention is 60 and width 10(60+5+5=70)
