1. Steps 1-4 1. Sketch the one position in the correct orientation.
2. Project step 1 onto surface
3. Sketch the next position in the correct orientation.
4. Project step 3 onto surface 1 3 2 4

2. Steps 5 & 6
5. Create a datum plane at an angle half way between the to previous sketches. In this example since the sketches are at 90° to each other this datum is at 45°
6. Sketch on the new datum the full slot. You will need to do “use edge to get the splines from the projected circles. Make the to sides of the slot tangent and trim. 5 6

3. Step 7
7. Project step 6 onto the surface 7

4. 8. Create a surface using the variable section sweep tool along the step 7
This is the key

5. Step 9
9. Solidify the surface to create the cut.