it looks a bit wobbly, you may be better off, using tube instead of angle.
But keep in mind, that those boxes are rated for a few kilos only.
Making the support rock solid, may end in fractures of the bike frame, where the structure is attached.
So, just don`t overload..

salu2,
joe

__________________
Saludos,
Joe
http://web538.ypsilon.ibone.ch/index...d=89&Itemid=42

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