A (retired) professional, also a volunteer on "our" ship.
Normally he does welding jobs during the week but now on a saturday he helped us to repair a weld at the top of a gasoil pressure tank.
It was hard to find where the tank was leaking and it appeared to be a very small leak in a very old weld... Behind a few layers of paint so hard to find.
But after emptying and venting the tank and part of the fuel system he could fix it.