It dpends on what you want. The way you modeled the profile of your clip the edges of the opening are at 90° to each other. I made the wedge shaped cutter with the same angle so the resulting gap in the four different clips are all 90°. If you want a different angle for each one you would have to model different cutters.
yes i realise now that the radius doesnt matter so long as its a quarter circle it will work.