Caring for clubs

hi i have recently begun using johnson & johnson baby oil to apply to my iron heads every few games or so ( according to advise from a previous post which i cant seem to find ).

can anyone advise whether it should be applied to the shaft as well or if not how do i look after my iron shafts.

also will it work for my putter also? i use the odyssey black series and am worried it will affect the paint job.

thanks in advance.