Surface filet issue

Hi,

I have the age old problem of failing fillet.
I am trying to round off the edge between the roof surface and the wall surface, all around with a constant radius. I have tried everything I know but with no luck. Any advice? Could it be due to different ways each surface is created? (NetworkSrf, Sweep2 and a rebuild of a trimmed sweep2)
coachroof issue.3dm (1.4 MB)

You will have problems with almost everything when you make geometry like that.

I would suggest starting over using a much looser tolerance
A tolerance of .1 would be better for a model this big. Or you could change the units to meters. Then focus on making simpler cleaner geometry It looks to me that you could make the side surfaces accurately with surfaces that have 20 X 2 control points.

And you should be trying to avoid making surface with multiplicity of knots. Some of your surfaces have thousands of fully multiple knots. If you make surfaces like that you are going to have trouble

I must agree with the previous speaker.
dupedge the small vertical edge, go to “rebuild” and you will see that this small straight line already has 76 control points!!! fillet cannot do it, because the two surfaces cannot be joined together. You could try pipe, trim and blendsrf. The better way would be to redesign it and keep the number of control points as small as possible.

best regards

coachroof

Thanks for the suggestions guys, I ended up rebuilding the whole model with much less control points!
But that workaround with a pipe will be worth a try in the future.