Say you are securing one metal plate to another using a bolt, nut and spring washer (split washer). Does it matter which side the washer goes - the nut side or the bolt side? It’s much easier to put it on the bolt side but someone told me it’s wrong (without providing any logical reason).
Also, many nuts have rounded edges on one side. Does this side face towards or away from the metal plats I’m trying to bolt? I always thought the flat (non-rounded) side faces the plate, but someone else said he thought that was wrong.