Fitted lid on irregular model

[Anonymous]

Hi.

I am looking for some advise on a project I am working on. I want to model a hollow stone shaped (see images attached) object in 3D max that will be 3D printed. The stone shape has to have a separate top and bottom so that I can embed electronics in it afterwards. My problem is I am finding it difficult to create a lip that will enable the top & bottom to securely fit into one another, so that when someone picks it up it will not fall apart. I was thinking of using a system like the attached image Lip_Profile.gif. I have no problem modelling something like this on a regular box/sphere using a lathe, however I can't find a technique to model this on irregular objects. Would anyone know of a technique that would enable me to model such a fitted lid? I would really appreciate any advise that would send me in the right direction.

Cheers,

Trevor

[Steve_Curley]

Create an Editable Spline which describes the "uneven" shape of the joint - all around the object.
Create another Spline (separate object) which is the profile (as in your image). Apply a Bevel Profile (or possibly a Sweep) to the 1st Spline, pick the 2nd as the profile. Repeat for the other "half" of the model. If you do it carefully they should match up as shown.
You can then create the rest of the "rock" by normal Poly Modeling.