1" box/tube 1.5 or 2mm wall should be strong enough. You'd probably want to gusset the corners. Also has the bonus of not bouncing a ball straight back out (tried it before)
@O'Shane started
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1" box/tube 1.5 or 2mm wall should be strong enough. You'd probably want to gusset the corners. Also has the bonus of not bouncing a ball straight back out (tried it before)