Fillet between two complex surfaces

[Scott Gammans]

I am looking for tutorials that show how to fillet the joint between two complex surfaces in LightWave.

One technique that I have been reading about involves booleaning one object into the other and using Rounder to fill in the seam. I've gotten this to work on relatively simple joints between simple shapes where one object drills into the other at a perpendicular angle, but when the shape gets complicated and/or the angle of incidence is other than 90 degrees, this technique results in a mess of 5-point polygons (or worse) at the intersection seam which Rounder can't handle.

From what I've been reading, this is a weakness of polygon modelers like LightWave, and that fillets are second-nature in NURBS modelers. Well, I don't have a NURBS modeler like Rhino--I have LightWave. So what's the LightWave solution to this issue?

Thanks...

[Matt]

It would take a lot of messing about to get this to work with polygons and isn't unique to LightWave - all poly based modelers suffer from this.

The best way would be to use sub-d modelling, but even then it will require work to get the under-lying mesh right.

[Wade]

Playing some with rounder under oops no make that router uner the extend/more tab may help you out, or cause untold grief. I could bet something looking like a weld.

[Scott Gammans]

Playing some with rounder under oops no make that router uner the extend/more tab may help you out, or cause untold grief. I could bet something looking like a weld.
Wade, that was just a very general example I showed above. The actual two objects I'm trying to fillet are even more complex.

Matt, I'm getting the strong impression from nosing around various forums that LightWave isn't exactly the best modeler for mechanical visualization, and weaknesses like this are one of the reasons why. Fillets seem to be second-nature to a NURBS modeler, but all that LightWave has is a finicky Rounder plug-in that seems to barf on anything too weird. Do you (or anyone else) think that Newtek will ever address this shortcoming in Modeler?

[Dodgy]

I think it's more a case of the polygons which are too small too close to the weld. Rounder can only fillet out to the extent of the smallest poly next to the weld, whereas nurbs based modellers can reconstruct the surrounding geometry to allow the fillet to spread out more. This would be the case with any poly modeler I think, so perhaps you would be better served adding a nurbs modeler like Rhino (I hear good things about it) to your tool set.

Otherwise you could look at cleaning up some of the geometry around the weld to give rounder some roome to maneuvre.

[Scott Gammans]

Otherwise you could look at cleaning up some of the geometry around the weld to give rounder some roome to maneuvre.
I'm beginning to understand how Rounder works, so that actually makes sense... I can also see why three-point polys on either side of the weld would be a bad thing.


nurbs based modellers can reconstruct the surrounding geometry to allow the fillet to spread out more. This would be the case with any poly modeler I think, so perhaps you would be better served adding a nurbs modeler like Rhino (I hear good things about it) to your tool set.
Bah, this is a hobby, not my day job. I'm already sleeping on the couch for the $1000's I've spent on computers, monitors, and this software... I'd be shacking up with Fido in the doghouse if I ponied up another $800 for Rhino! :eek: So, I need to learn how to do this "the LightWave way". I just wish that "the LightWave way" was a little less clumsy and time-consuming, and I'm pretty sure I'm not alone in that regard.

[Dodgy]

Bah, this is a hobby, not my day job. I'm already sleeping on the couch for the $1000's I've spent on computers, monitors, and this software... I'd be shacking up with Fido in the doghouse if I ponied up another $800 for Rhino!

LOL Guess that's why I'm still single :)

[cathuria]

I've tried the Rhino demo and was impressed, and although I can afford it, I haven't found enough reason yet to sit down & learn a new modeling tool -- maybe one of these days.

When faced with a problem like yours, the first thing I do is ask myself if it can be better done in subpatch modeling. If not, I cheat. It does take some plug-ins and a few cheats, but it works.

First, keep the sphere and the cylinder as separate elements. Cut the cylinder at about the right place and bevel or extend the end out to give you room for the fillet. Then use the wonderful KO_POINTFIT plug-in to wrap those points around the sphere. Then use Rounder as normal to get the fillet you want. Finally, you might need a little hand-tweaking to make sure all the poly's in the two objects overlap properly (I always tuck the outside points a little inside the larger object.
With a good surfacing job, it should look near enough to seamless in Layout.

[Ron Schatz]

Just how complex does your part need to be? maybe you could use a edge shader like edgeFX on simple seam or chamfered connection, if not, then Rhino is the tool you will use. Or fake it solid drill into the base part to get the intersecting points, make poly p and bevel out your shape to your fillet needed (note you need to drill with the size of the part plus the size of the fillet your using) then kill this non-planar poly and point weld the rest as needed. This Object just has Smooth on.
Good luck