Box with cover, hinge and lock

I designed a box to handle paint bucket with a hinge and a little lock to keep it closed.

Inside mesurement : 18cm x 13cm x 7cm + Cover 1.4cm, round corner R=0.55cm
Outside mesurement : 18.8cm x 13.8 x 9.2 (1.8 + 7.4), round corner R=1cm