What do you use to clean your strings? I have steel / nylon / copper strings to clean. 'Isopropanal' has been recommended--but hard to get. I have a spray can of 'Maplin's Switch Cleaner'. Has anybody used it for string cleaning? It says on the can: 'A general purpose cleaning solvent that removes stains,coatings,printing inks,oil,grease and dirt. Highly efficient switch cleaner. Safe on most plastics.' Any Bass playing chemists out there?