Mould creation

Does anyone know if there is a fast way (or an extension) to create a negative from an complex object ?
I want to make a drawing of a mould from an object but it`s really time consuming to draw off the object.

If you’ve already got the object drawn it should be pretty straightforward. What kind of mold do you want? Two pieces? Is this for sand casting or for some other casting process? Does it need to have a core? Can you show at least an image of your model?

Here’s a recent example I did. The yello things are the patterns and cores for casting the things on the right.

And a quickie of the mold.

It might be as simple as drawing a box to represent the mold and using Subtract from the Solid Tools to subtract the the object’s shape from it. Or you might make a copy of the object and erase the part that won’t be in the mold and then draw a box around it leaving a void.

A very basic method.
Basic mould