topic Re: Shell Modifier causing odd geometry deformations in 3ds Max Modeling Forum

Shell Modifier causing odd geometry deformations

Anonymous — Wed, 30 Mar 2016 12:32:43 GMT

I'm working on a school project, and I've been making various models for use in the apartment I'm making. Latest thing for me, was a glass vase. I used a technique from a tutorial I read online (can't find it), but the basis was make a line and draw half of the object, apply lathe modifier, apply shell modifier, edit poly modifier (fix any edges if needed), and then apply a turbosmooth. I was successfully able to do this with a wine glass, but now when I try to do the same with a vase, it gets messed up.

Here's the process I went through:

1. Make Line

2. Apply Lathe

Here you can see some odd shading, but so far doesn't actually affect geometry in anyway.

3. Apply Shell (you can already see a bit of deformation at the bottom)

And here's what the end result is, I have no clue why its doing this, I've double checked everything, tried remaking it from scratch, same problem shows up.

Not sure why its doing this, but if anyone has any suggestions or possible alternatives, feel free to let me know!

Re: Shell Modifier causing odd geometry deformations

Anonymous — Thu, 31 Mar 2016 14:04:08 GMT

Make certain that the end of the line at the bottom ends at exactly the centre point, coincident with the lathe axis.

It looks as if the line extends beyond the axis.

Re: Shell Modifier causing odd geometry deformations

Anonymous — Thu, 31 Mar 2016 14:59:20 GMT

Yeah I see what you mean by it extending beyond the axis, but I can't seem
to get it to stop at the axis. I turned on grid snap and snapped it to the
axis but it still extends past the horizontal axis. Its pretty frustrating,
is there some sort of setting I'm missing?

Re: Shell Modifier causing odd geometry deformations

Anonymous — Thu, 31 Mar 2016 16:38:39 GMT

If you have the end vertex selected, you can manualy place it precisely if you open the Move Transform Type in, and set the number to the same as the axis position.

Re: Shell Modifier causing odd geometry deformations

Anonymous — Thu, 31 Mar 2016 17:02:17 GMT

A tip to ensure that the Lathe modifier axis is centered around a desired point -

- just before you apply the Lathe, Select your Line object , go to the Vertex sub-object level

- select the vertex where you want the Lathe axis to be centered, in this case the last vertex at the bottom

- Apply the Lathe modifier, it's axis should be centered at this point.

- You can go back down the stack to the Vertex sub-object level to deselect the vertex.

Other things to always consider-

- Weld core option, under the Parameters Rollout of the Lathe Modifier

- Straighten Corner option, under the Parameters Rollout of the Shell Modifier

Would like to add that this method of selecting a sub-object before applying a modifier also works for a few other modifiers e.g. Symmetry (in which case, you could also use an edge selection to dictate the axis of operation)

Re: Shell Modifier causing odd geometry deformations

PROH — Thu, 31 Mar 2016 17:30:29 GMT

Hi. Looking at you're pictures, it looks like your pivot is NOT placed correct. The pivot should be placed at the center point for the lathe, and the vertex at the center (bottom) should in this case be a "corner" (select vertex, right click, select "corner"). Otherwise things like your overlap happens.

Hope it helps