Paint Prep Cleaning Practices
Surface washing is an important part of any refinishing work. Prior to starting any job, you should
initially wash the old paintwork with a mild detergent to remove dirt and other water soluble
contaminants that may hide another problem.
The initial wash will remove bugs, bird droppings, sap, coffee, pop, grime, dirt, dust, blood, salt among other things that make its way to the surface of the vehicle. It also allows for a more accurate analysis of the job before you begin. Other benefits that go unnoticed is that it increases the life of sandpaper and saves you time and effort sanding.
Once you are looking at a clean surface you can take advantage by inspecting for things such as:
Rust & Dents
Chips
Scratches
Damaged Moldings
Cracking
Clearcoat Imperfections
Your soap and water will effectively remove water soluble materials, however other contaminants may still exist and require a special chemical cleaner to properly remove them. Chemical cleaners are used to remove wax & Silicone, oil, tar, grease & mold release agents from raw plastic materials. You should use an appropriate chemical cleaner before beginning any sanding or grinding operation.
Wax & Silicone Removers:
are solvent based cleaners used to remove wax, silicone, grease, oil & tar to prevent fish-eyes caused by these contaminants.
Plastic Cleaners:
Are solvent based cleaners used to remove mold release agents from raw plastic materials (not primed plastic) they can effectively remove these contaminants without damaging the integrity of the plastic.
Alcohol Based Cleaners (antistatic)
These cleaners are designed to remove mild contaminants such as fingerprints that may have been obtained from some point in the repair process. It is not as strong of a cleaner as a wax and silicone remover but is also formulated to reduce static unlike the wax and silicone cleaners.
Water Based Cleaners
These are often used as a finial cleaner to remove sanding residue and other light contaminants. They are generally low VOC cleaners and can be further diluted with de-ionized water.
With any cleaner, you want to try to use a two rag system, wipe on & wipe-off. Small pressurized spray bottles are also handy to make life a bit easier.