Complex 3D Modelling

[ddocg]

Hi, first post here!

Can someone explain to me the options available to create the lower half of a Dalek?

In essence i have a larger ellipse as the base, this is copied and scaled down then moved perpendicular with its centre offset.

I would like to create a solid from the 2 ellipse or how do i create a solid that tapers from the large ellipse to the small ellipse??

Your help is much appreciated.


Dave

 

[rigill]

Combing solids.

I haven't tried this and I may be wrong, but I think there is a 3D command out there called "MELD?" which can be used to join 2 solid forms together. In your case a small ellipitical shape to a larger one. Create the 2 seperate solid shapes and then located them in the correct locations, then trim, fillet, chamfer off the pieces you don't need. And then save it as a whole, or maybe a 3D block.or Search a 3D block library for a shape that is similiar or already done for you and modify it to fit your needs ....Hope this gives you some ideas.

 

[Pocket]

Solid modeling:

I tried taped extrusions in AutoCAD 2002 and it failed to work on elipses
Im not sure if this was remedied in later versions, I do know that the default extrude command does not include a taper command in 2007.

You might not be able to do this using a true elipse
A collection of circles trimmed down to look like an elipse will still allow a tapered extrusion but the model wont be 100% accurate anymore

Surface modeling:

With your upper and lower elipses already made you can do a ruled egde to get the angled sides. A simple region/face would make the top/bottom

The downside to this method is you cannot modify the shape further

Lisp:

Mesh to solid on a ruled edge will make a good rough model that is highly dependent on your surface tabulation values. Since ruled edge only makes flat faces - alot of them - you wont get a true eliptical curvature from it

The plus side is you can manipulate it further

 

[gordonp]

Extruding Elipse

My version 2007 extrudes an elipse just fine and after you select the object to extrude you may enter T for taper angle, then the distance.

 

[hakor]

complex 3D modelling

Hi,

In 2007 you can use the loft command to do this.
Just draw a true ellips, copy it and scale it as you want.
Use the loft command and click both ellipses, than follow the options,
I mostly use: "cross sections only" , then I check the options "smooth fill" and "close surface or solid".You can also connect an ellipse to an rectangle, or any shape you want.