Createing an edge fillet with a radius equal to the thickness of the solid?

How do you create an edge fillet with a radius equal to the thickness of the solid? I’ve done so with other models, but in the below model, when I try to perform an edge fillet with a .75" radius on a .75" thick solid, I get a broken solid. Any suggestions? Thank you in advance.

fillet problem.3dm (597.6 KB)

i will make a blind suggestion since i cant read version 6 models right now. remove the lonely surfaces and create from the last ends of the remaining fillets a sweep2, should be done pretty fast.

You can’t use a fillet command. The Fillet commands ride along the surfaces to be filleted. This means that the radius has to be less that the width of the surface it is to follow.

You can draw an arc (or any desired profile curve) that fits the two parallel surfaces. Then use a 2 Rail Sweep to create the surface you’re after.

Makes sense John. Thanks for the quick reply.