topic Re: Huge file sizes when deriving and large assemblies in Inventor Forum

Huge file sizes when deriving and large assemblies

erotbart — Tue, 04 Jun 2024 18:24:27 GMT

Hi all,

I'm working on large (ish) aircraft assembly and I'm trying to make the assemblies more manageable by using derived/simplified files (and suppressing to link to the original assembly to avoid issues), but I've discovered a weird issue while doing so:

I have a large structure assembly that contains many parts, this file size is ~35 MB
If I drop in this assembly into a new assembly file (to be used as reference), the new assembly file size is ~24 MB
If I derive the structure assembly into a part file, the size of the file goes up to ~242 MB!
If I drop the derived part into an assembly file, the new assembly file size is 254MB!
This really blew me off, I was expecting the assembly file be very small since it is only pointing to the parts/assemblies.

I ended having a relatively small assembly that is 1.7 GB !)

Is there something that I'm missing?

What can be done to reduce file size and to create a lite assembly?

What is the best practice to keep the files manageable?

Thanks,

EItan

Re: Huge file sizes when deriving and large assemblies

Frederick_Law — Tue, 04 Jun 2024 18:48:36 GMT

The derived part file need all the parts from the assembly.

Re: Huge file sizes when deriving and large assemblies

erotbart — Tue, 04 Jun 2024 19:36:38 GMT

I can kinda understand what you are saying, but it doesn't explain why the assembly file becomes so massive after I drop in the derived part...

Re: Huge file sizes when deriving and large assemblies

CCarreiras — Tue, 04 Jun 2024 21:45:54 GMT

Hi!

This is odd....

What Inventor version are you using?

Have you all updates installed?

Have you tested to make a simple derive and checked the file sizes? (it could be this particular file related)

I test to make a derived part (with just one part).

The new derived file is lower in size than the derived source file.

Re: Huge file sizes when deriving and large assemblies

jtylerbc — Tue, 04 Jun 2024 22:13:23 GMT

That last assembly file being so large seems odd. I don't know what is causing that, so this post isn't going to address that part of the issue.

However, the derived part file being large isn't unusual. When you compare the size of a derived part to the source assembly, you shouldn't compare it to just the assembly file itself. You need to compare it to the total of the source assembly and all parts and subassemblies contained in it.

It's a fairly common misunderstanding to directly compare the derived part (242 MB) and the assembly (24 MB), and say "It got way bigger!". But it seems that way because you're not comparing the correct things. You're going from a bunch of smaller files with links to a single larger file without links.

Re: Huge file sizes when deriving and large assemblies

johnsonshiue — Tue, 04 Jun 2024 22:34:18 GMT

Hi! I guess you have Express mode turned on. Close all files and go to Tools -> App Options -> Assembly -> uncheck "Enable Express mode" at the bottom. Open the assembly and save. Is the iam file smaller now?

Many thanks!

Re: Huge file sizes when deriving and large assemblies

erotbart — Wed, 05 Jun 2024 11:47:18 GMT

Thank you @johnsonshiue , it worked! the file size went from 350MB to 128 KB.

Regarding derived parts size, I understand and accept what you are all saying.

Thank you all for the help!