if it’s the model it’s the model really… at times when they are designed the people don’t make things solid, leave holes from patched up things and such. Then when you or I go in to “enlarge” cough cough it ruins the model.
I just was dealing with a spaceship you saw in the other thread. utter nightmare and i know it ain’t my printer. Like you I know something off. it’s the model - sometimes we don’t get lucky and it’s easier to go remake one yourself to avoid that other persons issues haha 