I am a 'novice' machinist and I am doing some overdue maintenance on my Lathe (1929 South Bend 9X48) and I was wondering what is the proper lube for the exposed gears IE. the back gears, slides shaft gears etc. Previously I greased them but they picked up a lot of foreign material over the years. They do need some kind of lube so what is the best for them? Thanks.