I am assuing that we are on the subject of a bolt rusted in a steel part or something similar. Anyone ever try sulphuric acid from the hardware store? It is acid and you must think it out before applying. Think about the parts you want to separate, personal protection (eyes, skin, clothing, etc.), the physical location of the parts to be separated and how gravity will affect the application (water runs downhill type of thing), and what is near it. Also handy to keep a container of water large enough to place the part in to neutralize the acid. A large container is desirable. Also, be prepared if you spill some where you do not want it. I have used it many times and it will get rid of rust (and I have the holes in my clothing to prove it). An acid brush works well in applying. Like I stated, it all depends on the situation. When finished, the metal will be ready to rust and I have experimented with alkaline cleaners when rinsing to help neutralize the acid - Purple Power comes to mind. Is it better than just plain water ????? Makes me feel better using it as the final cleaner in the rinsing process before drying.
