But you have pic's
If only loose after tightening, have you tried making the gap in the clamp bigger, assuming yours are lead?Is there an easy way to replace the battery terminals clamps without replacing the cables? Mine have seen better days and one of them can still be moved by hand after tightening it.
BINGO!Yea take the clamp off the battery and run a hacksaw blade in the gap all the way around that should allow you to get them tight.