How to treat the surface after epoxy resin curing? Rear painted parts
A customer has encountered a problem: due to the production needs of the product, the motor mold needs to be sealed with epoxy resin. Due to the thin packaging layer, the product is cured and the mold is opened, and some small pores often appear on the surface. Secondary repair is needed to achieve a beautiful appearance. The surface was filled with atomic ash and then treated with self spray paint. But the effect is not very satisfactory, and the adhesion of the paint is not very strong, which is easy to scrape off. I don't know if there is a better surface treatment method. Or materials like atomic ash require black, easy to fill and polish. The current epoxy resin model used is EF400 resin with curing agent, and the trial methods are as follows:
1. Vacuum treatment of the resin before packaging cannot completely solve this problem, and the problem of air holes still exists after packaging.
2. Using epoxy resin to repair the pores for the second time, due to the strong fluidity of the resin, difficult to control surface smoothness, and high hardness after curing, it is not easy to polish.
Let's first take a look at the response methods adopted by the customer:
1. The vacuuming and bubbling operation is correct, as it can remove many bubbles generated during stirring and mixing.
2. When using epoxy resin for secondary repair, the resin shows sagging, which can be solved by adding white carbon black (fumed silica). As for the issue of high hardness and difficulty in polishing, this is a double-edged sword, sometimes worth it for better bonding.
The advice for customers is:
1. The semi paste two-component epoxy resin putty is used for repair. It can be gel and cured in 30 minutes. The operation is very simple. Because of the same system, the secondary bonding of the paint surface will not be affected;
The second is epoxy resin+white carbon black repair treatment, but it will solidify slowly.
Many times, large texture gaps in reinforcing materials are potential shrinkage points for epoxy resins. You can consider whether to reduce the surface porosity of epoxy resin components by spraying a layer of easy to polish adhesive coat first, if the process allows. As for which one is more suitable for you, you need to comprehensively compare and consider it yourself.
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