I have one small problem. This is what I have done so far.

1. Created Grid and Cylinder (Both are NURBS)
2. Use Surfsect tool to make nice cylinder shape hole.
3. Next step is to use Round tool to make nice round surface on the edge.
But when I do this I can't see any diffrence. When I change radius option in round tool I can see it but it dosen't trim grid edges away automaticly. I have tried to use trim option but I don't know the right order of node tree. Here is a pic.

I don't think there's any way to get a nice quick bevel in this scenario. You could use the Fillet SOP to generate a Tube > Tube fillet, then trim a grid with a tube/circle and merge the results. To be honest, I think it's more trouble than it's worth and you would probably be better off working with polygons. With NURBS in Houdini there's too many accuracy issues and you always have to worry about seams.

I think Round SOP generates fillets only between two surfaces (so no trim curves involved). For your specific case, the one to use is the Bridge SOP, but indeed there might be accuracy issues.
http://www.sidefx.com/docs/houdini9.5/nodes/sop/bridge [sidefx.com]

Dragos

Thanks for help. Here is a picture what I'm trying to model. I'm modelling the brakes of motorcycle and I was thinking that NURBs would be the best way to go.