Locomotive nicknames?

Question

Why were the following given the nicknames?

Class 25 - rat

class 31 - goyle

class 47 - duff or spoon

class 50 - hoover

class 20 - chopper

and why are trainspotters called bashers or gricers?

Answer 1

as i understand it,Great Central Railway 'spotters' were called gricers,and when you tried to go around a shed,then you were doing a 'bash',i'm more of a steam man,so don't know for sure,about diesels,i think it's to do with the sound they make

Answer 2

rat- the sound they make, rat rat rat

goyle- the way they look, they are quite ugly but dont they thrash!

duff- they are a bit duff

spoon- the horn-spooooon

hoover- they had cooling units that sounded like hoovers

chopper- they really sound like helicopters when at full throttle

bashers are not really trainspotters but men(only men) who spend their whole life like me wanting to ride beahind and on as many proper locomotives as possible, especially class 37s, 20s, and 56s

and as for gricer i dont know.