In article , "Julian Bradfield"
says...
I'm thinking of putting up some cable-suspended shelves. I know where
to get cable and shelf retainers, but I don't know what to use for the
shelves, since they have to be quite wide: total width 164cm, and it's
only possible (read easy) to put cables at the ends. Worse, their
intended use is books, of a fairly heavy kind - say 20-30kg/shelf, for
luck.

What material can make shelves 160cm long, 20cm deep, with an SWL of
100kg, with end support only?

It's not so much ultimate strength you need to worry about as
stiffness - they won't look good if they sag in the middle.
I'd use something like a 2x1 frame glued in a sandwich of 9mm ply.

Followup: are the shelf retainers (from Flints) up to that load,
without being so tight as to damage the cable (I was thinking 3mm
cable)?

What shelf retainers are those?