How to Unscrew the stuck bolt and leave it whole

Each time, approaching to any mechanism, has long been requiring inspection and maintenance, the owner disappointing scratches his head. Outside the mechanism, usually already pretty spoiled by rust, and probably all connections are firmly grabbed. And so every time, before you Unscrew the stuck bolt. All the hunting to work to beat!
And here's what happened. Tightening the bolt was not achieved the required tightness in the threaded joint has been infiltrated by moisture, and the reaction of water with iron in the presence of oxygen gave a hydrated hydroxide of iron, i.e. rust. She scored a threaded connection is jammed. So how to Unscrew the stuck bolt if the connection is not spun over the years?

For starters, you can try to dissolve the rust. It makes good glycol, an ingredient found in antifreeze or brake fluid. Soaked rag is placed on the stuck thread, the glycol will penetrate rust, loosen it and Unscrew the rusted screw will soon become easier.
Microstory thread also plenty of kerosene, and solvent white spirit. Therefore, the craftsmen from garages in difficult situations I like to use aerosol WD-40, half consisting of white spirit. Liquid to better penetrate into the threads, you can gently tap with a hammer on the bolt head. Wait should be no more than 10 minutes.

And there is, so to say, the scientific method, how to Unscrew the stuck bolt. Around the bolt heads need to build a side from clay or wax, inside put a little bit of zinc and pour the sulfuric acid. Fastening it to corrode in no time, because they immediately attack the rust and react with the zinc, will start on the surface to recover the iron. The chemical reaction literally clean out the rust from the threads.
If does not work, you can resort to heating of the bolt, then you will need a gas torch (or soldering iron). Heated to approximately 230 degrees, the bolt needs to cool down. In the process of heating/cooling changing the geometry of the metal will destroy the rust so that the threads will be free for the penetration of liquid lubricants. And then there is problems with how to remove the bolt that should not be.

Loosening the hand should be of high quality, reliable and proven tool. Of course, not made in China. Carob keys in this case ineffective - they will get crushed the head bolts and knocked the hand off disruption. Use the swivel keys and heads. Undo the movements back and forth, vraskachku like cut the thread or pull out a stuck car out of mud. The penetration into the thread lubricant will increase.

There are also more radical and extreme ways to remove the stuck bolt. First top hammer headed hammer, tap the bolt head - it will break the rust. Then, using a chisel or sturdy screwdriver and hammer to tap out each face of the head, directing blows at the axis of rotation. In the majority of cases of stubborn bolts must resist and wriggle.

And the last. When you re-tighten the bolt, please don't forget about graphite lubricant, grease or motor oil. Then thread the long years no corrosion or oxides are not terrible.