Smooth union of surfaces

I am having trouble getting two surfaces to blend smoothly. The render reveals how this connection is abrupt and does not transition well. I have corrected the tangencies of the curve ends but the area in-between are still not as smooth as I would like (see rendering).

Help? Thanks TimTwistSept copy 2.3dm (183.7 KB)

Dear timepowers

looks like the tip you build is a 90 degree revolve surface.
both surface edges of the tip therefore are rectangular to World XZ or World YZ plane.
your cone-like shape isn t.
what you want is tangent or curvature continuity. between the cone-like shape and the tip:

rebuild the red curve to have curvature-Continuety (inside the curve)
_rebuild 10 points, Degree 3 Delete Original

build a helping-Surface to have something to define tangent direction or the curvature.
_extrude

Then _loft between the green and the red surface edge.
choose option tangent at start, tangent at end

or

build a _blendSrf between the two edges

hope that helps

best

Tom

Thanks. I’ll give that a try later today. Tim