Excessive file size?

I design injection mold tooling, and I am having a big problem with excessive file sizes on a few fairly simple parts. It's got to the point now where I cannot open the main assembly because it takes upwards of 30 mins to open, for a job that is only about 10% complete.

In comparison to other parts in the same assembly of the same complexity, one is 983MB the other is 50MB. 50MB is what I would usually expect to see for this type of part as the mold cavity is fairly complex (yet only 100MB). The part only has 14 commands and is still 283MB with all of them suppressed. The other problem part is 1.1GB and a comparison part of the same complexity is only 100MB.

It doesn't seem to be affecting all the parts in the assembly only a select few. I have used the same structure for the assembly that I always do and I have never come across this before. I've searched the forum for similar issues and have tried everything that I could find with no luck.

Does anyone have an idea of why these parts would be so large?

Thanks

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