Advices needed for making teeth joint

Hi,

As you can see in the photo, I am trying to create teeth joint to a custom brep thats open on the back. 

As I am new to grasshopper, I am facing some problems with managing the data to get the right plane to offset the curve in the two directions corresponding to their respective planes. On the right is actually the result I wanted and I have no idea if I am on the right track.

I realised there could be other potential problems in my definition, such as the teeth joints of the shorter curves might go off the curve and they might clash at the corners.

Thank you for you attention.