Paint Stripping Methods
The following article is designed to give you some basic information into the different types of Paint Stripping methods that are available. 
We will be comparing the following different methods of stripping paint:
Molasses Bath
Sand Blasting
Bead Blasting
Soda Blasting
Chemical Stripping
Molasses Bath
This is basically relying on a simple chemical reaction. The mixing of molasses and water, that is left to ferment for a few weeks, produces a mixture that ends up containing Acetic Acid.
Mix 7 litres of water with 2 litres of molasses and seal it in a container to prevent evaporation. You will need to store this somwhere downwind as it becomes a little on the smelly side. Once ready, the skin is removed from the surface and the rusty item needs to be immersed completely and left, undisturbed for a few weeks, so overall, this is a SLOW process. The beauty of it though is that it only removes the rust, not the paint, so good for partial stripping.
Basically what happens is the acetic acid reacts with the oxygen in the rust and when the iron oxide (rust) is all reduced the process stops, leaving the clean steel untouched. HOWEVER, you must clean the steel thoroughly and then treat it with a sealant of some sort, either a proprietory rust inhibitor or oil to prevent the oxygen in the air attacking the surface and causing rust again. This can occur in a matter of minutes, so you must do it straight away. This process will get all rust, not matter how hard, extensive or inaccessible to other methods, but it is time consuming and smelly. 
Sand Blasting
Sand blasting is the most conventional way of removing paint from a vehicle. You simply shoot sand at the paint, and it flakes off. The advantages are that it is fairly inexpensive (less than $10 for 80 lbs. of sand), fairly fast, and does not require very expensive equipment. You may purchase a decent sandblaster for less than $200. Also, it gets surface rust off very well.
The disadvantages are that it pits the metal (but is filled with primer), which can be a problem with thin metal, and it heats up the metal, again which can be a problem with thin metal because it can deform it and cause it to expand.
Bead Blasting
Bead blasting is similar to sand blasting, but it uses small plastic beads to "beat" the paint off. It does not pit metal like sand will, but it can cause more heat and does not get rust off very well.
Soda Blasting
Sodium bicarbonate blasting (soda blasting) is a non-hazardous, food-grade material that is an effective blast media for most industrial and commercial cleaning and coating removal applications.
Baking soda (sodium bicarbonate) can be dissolved and washed down the drain once blasting is complete. If the material or coating removed contains contaminants, they can be removed with specifically designed treatment equipment.
Soda blasting is abrasive enough to remove coatings or process residue without the surface damage typically associated with other abrasive blasting media such as sand.
Soda blasting can replace solvent use and reduce hours of manual cleaning.
Chemical Stripping
Chemical stripping, once condemned for the dangerous chemicals that it included, has become much more enviromentally friendly in recent years. New formulas that are non-toxic and don't smell nearly as bad have been on the market for several years now. The advantages to it are that it is fairly easy to do (simply spray or apply the stripper, wait, then scrape off), and it does a thorough job of removing paint.
The disadvantages are handling - it is still very corrosive and is quite painful if any of it gets on your hands or face. Also, it does not remove rust, is difficult to remove paint from nooks and crannies, and may not remove some primers.
Several chemical strippers are available, but they generally fall into two categories: liquids and pastes. The liquids are usually applied with a spray bottle, and the pastes are typically brushed on. Experience shows that pastes are usually more effective. To remove the paint, you simply wait about 5 minutes, then use a scraper or wire wheel to remove the paint. The paint should be soft, about like a piece of wet paper.
Caution is a must: you need to wear thick rubber gloves (no latex gloves or cloth gloves), a decent face mask (no dust masks - you need something with active charcoal), eye protection (glasses are okay, goggles are much better), and any other protection that you feel you need - arm and leg protection, face and hair protection, etc. Also, do not attempt to wipe your face with the gloves on. Paint stripper burns when it touches skin!
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