I need to add a fillet around an edge, with a constant (or approximately constant) width. I’ve tired the automatic tools and they all seem to struggle so have resorted to building manually. The result isn’t great - despite matching I can still see tangent breaks.
What process do you experts follow when matching surfaces like this? I always seem to end up chasing my tail - match one surfaces and another seems to lose tangency. I seem to be overlooking something.
File attached, I’d appreciate any tips. Many thanks.Radius Blend.3dm (227.5 KB)
Hello - if you are after G2, curvature continuous blends then I’d start by making the inputs G2 where possible - these are tangent
I think for maximum cleanliness, I’d do this ‘by hand’ like the attached - the transitions are Lofts, followed by MatchSrf
Radius Blend_PG.3dm (226.5 KB)
Is that what you have in mind?
I do actually want G1 rather than G2. The fillets need to match another adjoining component.
It’s the radius around the edge I’m struggling to get exactly right - I can see tangency breaks between the surfaces. It’s close but not quite right.
Hello - what you show is tangent - the false-color display. The ‘reflection’ having a sharp break in direction indicates G1 of the surfaces there. (which does not in itself make the transition nice, but it is tangent)
Making the side surfaces, the sort of conical ones, G2 to the arc across the top would be my first thought to make this all look better with G1 fillets.
Of course - I was forgetting tangent can have that crease.
Thanks for your suggestion, Pascal. I’ll see if I can make that change to the conical surfaces. They need to match another component but I think I might get away with it. I’ll have a play.
@MisterB, another way would be to replace the bits that do not flow well with a new surface -
that has new rails on the existing conical and top surfaces that flow a little better. This leaves the existing surfaces alone where they meet up with other stuff.
Hold on a bit and I’ll post a file. Because this is a single surface hooking up to two not-G2 surfaces (at the top) I had to insert a bunch of knots to allow MatchSrf to bring it close enough to join up. The top and conical surfaces are re-trimmed with the existing long fillet edge plus the new red blend curve.
Radius Blend_PG.3dm (184.4 KB)
That looks much better, Pascal. Thanks very much for your input. Replacing the two fillet surfaces with one definitely helps.
I’ll have to do a refresher on insert knot - it isn’t a command I’m very familiar with. I’ll work through it in the morning and post again if I get lost.
@MisterB - it could be two surfaces - the key, I think is that the top rail is made from a blend curve and not strictly a true fillet rail.