Hi - I have a Morso 3440 which had previously been stood outside, consequently the internal cast iron sides with the owls have rusted heavily and pin holed (well bit bigger than a pin!) at a few points. I have attempted to patch weld with some success but was wondering about creating a supplementary steel (4mm) fire box - sides and baffle (the baffle has gone) with the cast iron case. Anybody tried this approach? Am I being totally over simplistic?