Powder paint peels off
Powder paint allows to obtain a perfectly uniform and maximum quality coating. But only if the technology of such coating is strictly adhered to. If you do something wrong, the coverage will be defective. For example, craters will appear after painting, the paint will peel off.
There may also be problems with powder application. The paint may not simply settle to the surface or gather in one place, leaving part of the product uncovered.
Each of these defects has its causes. In today’s article we will find out why powder paint peels off and what to do about it.
Reasons of flaking
The first reason of peeling off of paint may be poor quality material. Even the best specialist will not be able to get quality coverage if it works with bad powder.
This defect can be caused by poor cleaning. Cleaning is the most important thing in powder painting. And a poor preparation of part can cause not only peeling, but also many other problems. This also includes poor degreasing of the product before painting.
The formation of craters with subsequent peeling off of the paint may be caused by too high a temperature of polymerization or over-heating of the product in the furnace.
Dissolving of powder paint and backlogging may occur due to low adhesion. A low adhesion may be due to poor degreasing, oxide deposition, excessive thickness of the phosphate or chromate layer, not enough polymerization and failure to take into account the heat content of the product.
Also, the cause of the peeling off may be incorrectly selected primer.
These are the main causes of this defect. Of course, peeling can also be caused by specific causes. Only specialists will help to correct everything here. But before contacting them, you can try to fix the problem for yourself.
Removal of powder paint defects
First, you need to make sure that powder to be applied is good. If you are not initially convinced of the quality certificates, then this is the time to do so. Paints without certificates will never provide a uniform and durable coating. You can check the quality of the powder for yourself. There are several methods for testing paints. But some will need special equipment. If the quality of the paint is not good, you should change the supplier and all problems will disappear.
If all is well with the paint, then something does the painter wrong.
The quality of cleaning and degreasing of the product must be checked. The surface must be sandblasted and shot blasted before painting. And then additionally process with special means of rust, fats, oils and oxides. If degreasing is poor, you need to replace the degreaser or increase the processing time.
In order to remove the oxide coating, etching is used. Check the thickness of the coating after phosphating and chroming, adjusting these processes as necessary.
You may be using a bad primer, just replace it with another one. Consult with the manufacturer beforehand to buy exactly what you need.
It is impossible for the part to stand for some time before painting, otherwise dust will appear on it. And then the processing must start again.
If this is OK, check the polymerization furnace. Baking modes must comply with the manufacturer’s recommendations. The oven should heat the product evenly. Control measurements of temperature and time of polymerization should be carried out. It may be necessary to reduce or increase the temperature and time.
If you have tried all the above recommendations, and the problem of not sticking powder paint or then easily removed, then you should consult a specialist. There may be some specific problems in your production that can only be corrected by professionals.