Powder Coating Clinic: Touch-up Options for Powder Coated Parts

Q. I’ve been told that a powder coated part cannot be “touched-up.” I have some patio furniture that I had powder coated and the powder coating shop that did the work for me stripped the threads in holes used to rack the part. I can fix the threads by welding up the hole and re-taping the threads. The shop states the whole piece will need to be redone and they cannot address just the small area affected by the repair. Is this accurate? Is it true that powder coating cannot be touched up?


 

 

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Q. I’ve been told that a powder coated part cannot be “touched-up.” I have some patio furniture that I had powder coated and the powder coating shop that did the work for me stripped the threads in holes used to rack the part. I can fix the threads by welding up the hole and re-taping the threads. The shop states the whole piece will need to be redone and they cannot address just the small area affected by the repair. Is this accurate? Is it true that powder coating cannot be touched up?

 

 

A. You cannot touch up a small area of a powder coated part with powder. It will leave a visible parting line between the original coated area and the touch-up area that is dry and rough looking. You may want to consider touching up with a liquid paint. Typical aerosol paints will not have the same performance as the powder but they can cover up an area cosmetically and you should be able to match the powder color pretty closely if not perfectly. If the area is very small this may be acceptable, but you need to know that the aerosol is not as tough as the powder and it may rust or discolor sooner than you want. 

In some cases, a part is touched up with a color matched, two-component polyurethane liquid paint by brush or spray. The parting line may be visible but it is not very obvious if done properly. This will give you better performance. It may not wear or discolor at the same rate as the powder, so color match may be more noticeable over time. If you are concerned about the performance and want perfect appearance, you will need to recoat the whole part after you do the repair. The repair area needs to be cleaned (probably sanded) and then the whole part will receive a second coat. Hopefully, the powder coater will take responsibility for ruining the threads and do this at no charge. The extra layer of powder will be a benefit and will provide better wear over time. One caution: they will need to confirm that the two layers will have good inner-coat adhesion; they can do this by testing a panel to confirm good adhesion. 

 

 


Originally published in the December 2016 issue. 

 

 

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