PeachParts Mercedes-Benz Forum - View Single Post

pcmaher · #7 02-08-2005, 09:22 AM

One thing people have to realize is that powder coating is NOT the same as paint. There are two types of powder coatings. One is thermo-set, the other is thermo-plastic. For applications like your valve covers, the thermo-set type is used. Powder coat is actually made up of two components, a resin and a catalyst. Each grain of powder coating contains the two components. After the coating is applied to the part, it is heated in an oven. Once a certain temperature is reached, the two components cross link and cure. It is a very hard coating and is very resistant to abrasion, chemicals, etc. Once this cross linking has occured in a thermo-set, it will not be affected by subsequent high temperatures. It remains cured and hard (thermo-plastic powder coats will soften every time they are brought up to temp). It is extremely important to prepare the part substrate prior to applying the powder. It sounds like your supplier used appropriate cleaning and preparation techniques. However, if you're uncomfortable with the coating in the valve cover, it is not a difficult thing to remove it if your supplier has the proper equipment. Their sandblaster would do the trick, but a plastic media blaster would be better, as this media does not remove metal...only the powder. FYI, an experiment I did on powder coated panels simulated 10 years of outside exposure. The powder coating did not degrade at all.