Climbing gear made by small man after diamonds (3,5)

'climbing gear made' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'small man after diamonds' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'man' becomes 'crew' (crewing is a kind of manning).
'after' means one lot of letters go next to another.
'diamonds' becomes 'ice' (slang term for diamonds).
's'+'crew'='screw'
'screw' after 'ice' is 'ICE SCREW'.

'by' is the link.

Can you help me to learn more?