Exploring This Fillet Problem

[Gaurav_Chauhan]

Hello All,

I am having this issue with fillets in the highlighted areas. I am trying to explore how to fillet this region, and nothing seems to stick. If anyone has ideas on how I can tackle this area, please let me know.

I have tried a few things, but I cannot seem to get a nice flowing continuity.

Thank You.

Question For Fillet.3dm (339.1 KB)

[davidcockey]

FilletEdge results in this which is valid without any naked edges:

I’m guessing you want something different. What do you want? If you were given a physical part like this, a file to remove material and clay to add material, what would you do? In other words what is your design intent? Or do you need a design intent?

[Lagom]

You need to think about what shall happen in these regions.

Question For Fillet.3dm (2.4 MB)

[jim]

@Gaurav_Chauhan

If anyone has ideas on how I can tackle this area, please let me know.

I would use FilletSrf. Do it Like this: Question For FilletX.3dm (327.6 KB)

[Lagom]

This is one way how you could treat this region: FilletSrf > Extend > BlendCrv G2 > EdgeSrf > Match G2 > Match G2 OnSurface > Trim > bit o’ CP pulling for good G2.

Flipping G2 fillet.3dm (477.1 KB)

[Rhino_Bulgaria (Bobi)]

You can see a similar approach here, too:

Filling 6-sided holes in Rhino (tutorial 3 + BUG in Rhino 7)

Filling 6-sided holes in Rhino (tutorial 1)

P.S. The better way to match to a surface is to not trim the target surfaces at all, and instead use “Match surface” with the “OnSurface” command line option. That way, the resulting surface will require far less control points and if you split it into 2-3 pieces and shrink them, convert them to Bezier and match again each one individually, you can achieve single-span surfaces.

[brvdln (Brv)]

@Rhino_Bulgaria Your method in the tutorial video is quite creative — I’ve never seen it done that way before. Ingenious… I’ll probably try it in one of my next projects, even just to test it out.

[Rhino_Bulgaria (Bobi)]

I had a better video with a much cleaner result, similar to what @Lagom showered above, but I can’t find it at the moment. I used the “OnSurface” option there, whereas my two older videos above show regular matching to split surfaces.
A similar technique is also used to fill 5-sided holes.

My two videos show two different techniques:

1. From edge to edge;
2. From corner to corner diagonally.

[Tom_P]

just to add to the discussion - there is always 2 hierarchies if you follow the approach shown above:

green first

the green rolling ball / sphere is doing its job first,
then the violett, second ball/sphere is on top of it

violett first

reversed order

EDIT

other typology

i did not fiddle it till perfection - but to show the concept i like most from a academic point of view:

main steps:
(1) rebuild all neigbouring surfaces as non-rational.
current implementation of _matchSrf i missbehaving with “arc-style” (rational) surfaces.
(2) start with a simple loft

keep this surface as reference, split a copy into the 4 pieces.
(3) do several _matchSrf, optional changedegree / insert knot… cv massage… always feels a bit like alchemy
(4) vote for improvements in _matchSrf or use Wip 9 patch command as workaround

[Gaurav_Chauhan]

Thank You all for these creative solutions, I am going to apply them and get back with some more questions if that’s ok. Really appreciate your input.

[Gaurav_Chauhan]

These videos are incredibly helpful and I have followed your channel. Thank you!

[Gaurav_Chauhan]

I am trying to follow this but I use Rhino 7 so I am trying to follow your instructions. Thank you!