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Clear Matte Coat for Raw Steel

Hello.

I make modern contemporary steel furniture. One of my lines that I offer is hand sanded steel with a clear matte powder coat finish. The problem we are running into is durability of the powder coat and few occasions of rust starting from underneath the coat. With clear matte powder coating, as you well know, if it too much is put on or if the product is cooked too long the coat will come out with a yellow tint. Wondering if there is another way to protect the steel and to keep the clear matte look?

Thank you

Tony Blake Jr
Tony Blake Design - Wichita, Kansas
2000

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You stated that you prep your steel by mechanical sanding, but, you did not mention any type of conversion coating i.e. Iron Phosphate. The chipping and rust may be due to inadequate cleaning and lack of a conversion coating to inhibit corrosion.

Depending on the mass of the individual piece of furniture and the combined mass of multiple pieces cured in a batch or continuous oven, you may not be achieving sufficient "metal temperature" for the necessary length of time required to cure the coating. You also state that your coating is yellowing when you cure hotter or longer. I assume, (dangerous),that you're using an Epoxy Binder System. You might try a Low Gloss TGIC. TGIC's are less prone to yellowing than Epoxies. Good Luck! Mike

Michael G. Nugent
- Schofield, Wisconsin
2000

I'm constructing a trestle table, and the legs are made from 3" & 2" tubular steel. I like the way the steel looks in it's raw form, and I'm hoping there's a way to finish the metal on my welds and grinds to make it look uniform. Right now the places I've ground down are shiny. As you can tell, I'm pretty new to working with metal and welding - so any help is greatly appreciated. Thanks!

Denny Hostetler
- New Castle, Colorado
July 18, 2009