One of my friends is a mechanical engineer doing the most standard "nuts and bolts" form of engineering and by these standards he isn't even an engineer. I don'

One of my friends is a mechanical engineer doing the most standard "nuts and bolts" form of engineering and by these standards he isn't even an engineer. I don't think there are any reasonable English speakers who wouldn't say he's an engineer (if he wasn't you would need to rename the whole field of mechanical engineering). You can have an idiosyncratic definition for personal reasons but it's probably best to realize that it's not the general definition of the word.