Shrinkwrapping an assembly

[Anonymous]

I'm using the shrikwrap command in Inventor 2012.  I'm told this is a good way to reduce the size of a file as the assembly I'm working on will be very large when I'm done.  The assembly (.iam) is 61KB in size and after I shrinkwrap it and make it a .ipt file the size is now 124,480 KB.  Isn't the reason for shrinkwrapping to make it smaller?  Am I looking at it wrong?

[jtylerbc]

Yes, the way you're looking at it is a bit off.  The assembly file itself doesn't store the part geometry, just links that reference the part files.  The only actual geometry stored in an assembly file is assembly-level features (holes drilles in the assembly, etc).

To really come close to comparing the before and after for the shrinkwrap file size, you'd need to compare against the total file size of the assembly and all the associated part files.

[SteveMDennis]

What shrinkwrap really accomplishes is that you don't have to load the parts UNDER the assembly that you shrinkwrapped while maintaining the same geometry interfaces.

This is how it contributes to capacity savings.

[jtylerbc]

That's a much better explanation, Steven.

The point I was trying to make was that you can't just directly compare the file sizes of the shrinkwrapped part and the original assembly file, because of the way shrinkwrap is combining things.  The goal of shrinkwrapping isn't so much to reduce the actual file size, as to reduce the memory load the model causes when it is open.  The shrinkwrapped file will ALWAYS be larger in file size than the assembly file was.

Comparing it to the total of the assembly and all parts would be closer, but is still not really correct.  If you're looking to reduce the file size (so you can email it or something), shrinkwrap is not the way to do that.  If you have an assembly that's just too memory-heavy to work in, shrinkwrapping subassemblies can be VERY helpful.  As a user still stuck with 32 bit Windows XP, I can say that there are many assemblies I have built that I wouldn't have even been able to open if it were not for shrinkwrap.