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Paint adhesion to cold rolled steel

2004

We are buying 16 gauge cold rolled steel sheets, shearing into 1" strips and forming our artworks for exterior use. We currently dip paint our finished artworks in a quality flat black production enamel-dry and dip again. We currently use an environmentally friendly degreaser cleaner (Simple Green ⇦this on eBay or Amazon [affil links] ), the sheared 1" strips are hand cleaned - formed to shape and mig welded - then painted. All our products are for outdoors -year round)

Our question(s) is this.

Is this method of cleaning sufficient to give a lasting finish when painted? (we are new - want a good year 'at least' from our product)

Is there another cleaner-degreaser we should look at? (this is a home based business - rural area) Should we be cleaning with a chemical or acid type dip before painting? ( we require a 'good bite' by the paint on the steel)

Your assistance is greatly appreciated. Thank you in advance

Harold Langille
YardBirds - painted steel artworks - River John, Nova Scotia, Canada

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Harold,

There is no easy answer, but I have to say I wouldn't bet money that your paint isn't going to peel off or the parts start rusting. Outdoors can be pretty harsh on steel. You may want to explore some kind of cheap phosphate system (this gives you the 'bite", good adhesion and a bit better corrosion resistance....not sure if it is a good "garage" type of operation) or at least a good oil base primer.

The answer about the cleaner is easier. Take a finished part and inscribe a checkerboard pattern in it deep enough to pierce the paint. Take a piece of scotch tape and press it firmly on the crosshatched section. Pull the tape off. If your paint comes off with it your part might not be as clean as you think it is.

Good Luck

Trent Kaufman
electroplater - Galva, Illinois
2004

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You seem to be doing just fine with your current surface prep, if you are worried about your work rusting I suggest testing it to find out how will your paint will hold up. Make a salt water solution, add salt until it won't dissolve anymore, and let a piece soak in it for about two weeks. See how badly it corrodes (if at all), if it doesn't, you're good to go.

If you have problems try Rustoleum.

Marc Banks
- Elizabeth City, North Carolina
2004