When I copy and paste an object sometimes the object's stroke changes thickness

[lexa12345]

This has been going on for a couple of months. Preferences, everything has been reset and illustrator has been updated several times by adobe support team so I am here now for help. I draw many objects with the blob brush in their own file and then copy and paste them into a new file; then I will color the drawn object with the paint bucket tool and copy and paste it for use. Yet when I do this the pasted object's stroke changes thickness. Usually, it gets thinner but sometimes it gets thicker but it doesn't look to be the same thickness at all compared to the original object. It doesn't happen with all objects either but the workflow is the same for them. What should I be doing to prevent this? Thank you SO much for your help, hopefully soon.

[Ton Frederiks]

The Blob brush creates filled shapes but not strokes (but these filled shapes can be stroked).

Maybe there is some kind of snapping going on in the new document. Can you check the View > Snap To options? Snap to pixel?

[lexa12345]

Well, that did not change a thing but thank you. Otherwise, it appears that whenever I expand the objects I drew and colored in THEN copy and paste them, the thickness of the stroke stays the same. When I test it out for the ones without expanding them then copy and paste them, it appears the stroke widths change. Anyone know why this would work? 

[Monika Gause]

Can we please see screenshots or the file?

[lexa12345]

Yes, The one that appears with thicker lines is the copy and pasted one. The drawing was made with the blob brush and the paint bucket was used to color it in. What's happening? 

[Monika Gause]

Please show a zoomed in version. It would be nice if you could embed your screenshots in your post and just screenshot what's necessary.

Please do also show the outline view as well as the objects inside the layers panel.

[lexa12345]

Okay, when I zoom in on both objects the stroke weight is the same.