Working molds in reverse

Arthur,

Do you mean you want to create a virtual molded part from the mold assy. with all the runners and gates attached ?

I do this all the time just to check for parting line alignment, ejector pin witness lines, etc.. As far as I know, there is no quick and easy way to do this. What I usually do is create an in-place rectangular block that extends beyond the part boundaries in all directions, and subtract all of the mold parts from it. Then you can scale it by the reciprocal of the original shrink scale, and compare it with the driving part.

A little involved, but doesn't really take very long

Regards

Mark

ummmm...well more like this...imagine that you create a cube. Put the mold block around that cube in a assembly and then get the cavity. you can then go back to the mold block part file, use a line for a cut extrusion and get the left and right halves of the mold. Add keys and what not.

Here is where my question starts. Imagine that I make some change to the molds interiors. And now I want to put the two halves together in an assembly and in much the same way that I got the cavity, I would like to get what the positive of what the mold would create.

As I posted before, top down could work in this instance, but is that the only way?

If I understand you correctly then yes you can, just create a block identical or smaller then your original cavity block, bring both into an assembly and extrude " up to body " of the original. Then extrude cut your second block back to the surface of the cavity leaving a theorietical molded part. Oh yes, all holes in original part block must be filled or up to body command will not terminate in model.

Arthur,

OK.. are you trying to create standard inserts or something for a MUD type base, without having to actually model them ? You can do what you describe. I'm just not sure what it will buy you in the larger scheme of things.

What you should be concerned about (maybe) is having to many cavity features in an assembly. Or creating circular referances in the process. This can really slow things down, or even cause the system to hang

Please excuse my confusion and ignorance. I have my own custom mold base format, and don't use off the shelf sets very often.

Regards

Mark