How to remove rust from metal before painting?
The fact that the powder coating will forgive everything, it can cover oxide, oil, dirt ― huge mistake. The paint will definitely peel off and will have to be repainted. And this time you will have to clean everything properly.
Let’s start figuring out how to do it.
There are many ways. Every is suitable for different needs.
A good one, if the products are small, they are few. Or you need to clean a small area. As easy to use are grinders, electric brushes, needle cutters. But they require a lot of time and effort.
Cleaning by sand
Requires a separate room. Suitable for large, heavy structures. Much more efficient than sandpaper in terms of time and effort. Sometimes, instead of sand, cleaning is made by metal pellets. It is important that the fine abrasive particles are approx of the same size. Then the surface will be homogeneous after processing.
Damage to the surface will cause a risk of corrosion, and the powder will stick to it worse. This method sometimes is combined with thermal degreasing. Lubricants are also harmful for powder coating. Before cleaning the product is heated to 400°C, so the lubricant evaporates.
Ferrous metals are etched with acids, aluminum and its alloys ― with alkalis. Treated in special tubs, less often with a jet of solution. Sulfuric, hydrochloric, phosphoric, nitric acids are used for this. The iron in the tub must be kept up to 30 minutes at a temperature of 20 – 60°C. Then it is washed with water and dried. Such cleaning is quite expensive ― you need special equipment, constantly buy solutions, filter wastewater.
Prepare the surface ― this way the powder coating will last longer. Epoxy paint as a primer will add protection. You can find it on our website.
Remember that making the right choice saves from many problems. Call by phone +38 (044) 596 06 12, (067) 536 53 64 and get all the necessary advice.
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