For years, custom car enthusiasts were painting their frames, suspension components, headers, and exhausts with everyday automotive paints, only to discover after limited miles the framerails and upper and lower control arms were chipped and pitted from road shrapnel. And how about those chromed headers that turned gold and blue from the intense heat of the hot exhaust gasses? That was then, this is now.

Let's come out of the dark ages of coatings. Today's aerospace powder-applied coatings and ceramic thermal coatings can cure all of those problems.

Powdercoating:
This type of dry surface coating is applied as a free-flowing dry powder. The main difference between a liquid paint and a powdercoating is that powdercoating does not require a "solvent" to keep the binder and filler particles in a liquid suspension form. The powder is applied through a static-charged air gun or wand, which gives the powder particles a positive charge. The powder is then transformed from a powder into a melted coating by the heat of a curing oven. When it's cured, it creates a hard finish that is tougher and more durable than conventional paint.

Surface Preparation:
Removal of oil, soil, lubrication, greases, metal oxides, welding scales, and so on is essential to create a pure metallic surface. This can be done by a variety of chemical or mechanical methods. The most common surface preparation is media blasting, or abrasive blasting, which provides surface texturing, etching, finishing, and degreasing from materials made of wood, plastic, glass, aluminum oxide, silicon-carbide grit, and sand-blasting media.

Powder Application:
The powder is dispersed through a pneumatic gun that uses filtered, compressed dry air that is delivered at 20-30 psi. The compressed air is merged with the powder, which causes it to flow through the inner teflon barrel, thereby producing an electro-positive charge that attacks the powder particles, which are dispersed out of the gun barrel. The part being coated is grounded, so the positive-charged powder particles are attracted statically clinging on and around the parts surface. When the part is covered with a uniform powdercoating, the ground cable is disconnected from the part. The powder-coated part is then put into a curing oven for a certain period of time, at a certain temperature, which causes the powder to melt and flow-out.

Curing:
When the powder is exposed to elevated temperatures, it begins to melt, flow-out, and then chemically reacts to form a higher molecular polymer-like coating. This cure is called cross-linking, which requires a certain degree of temperature for a certain length of time in order to reach full cure and establish the full film properties for which the material was designed.

Powdercoating Advantages Over Conventional Liquid Paints:
*Powdercoatings can produce much thicker coatings than conventional liquid coatings, without running or sagging.
*Powdercoating overspray can be recycled achieving nearly 100-percent use of the coating.
*A powdercoated surface is more durable than conventional paint.
*Powdercoating production lines produce less hazard-ous waste than conventional liquid coatings.
*Powdercoated parts generally have fewer appearance differences between horizontally coated surfaces and vertically coated surfaces than liquid-coated parts.
*A wide range of special effects is easily accomplished.

Black Gold, a '57 Chevy pickup project buildup of Truckin', was trailered to Media Resurfacing Systems in Huntington Beach, California, where it was media blasted using aluminum oxide. It was then sent over to Specialized Coatings, which is also in Huntington Beach, to be powdercoated. The frame was rolled into the powdercoating booth were it was grounded with a clip wire. The DuPont Red Baron powdercoat was poured into the hopper. Martin Quezada used a Nordson Sure Coat tribo-electric gun to disperse the charged powder that statically clung to the frames tubular surface. After a thorough examination of the coating, it was rolled into a curing oven for 15 minutes for a primer cure. This caused the first coat to partially melt. The frame was then removed from the curing oven. It was once again grounded and given another DuPont Red Baron powdercoat, which would flow-out smoother and cure to a high-gloss finish. Take a look at these photos to get your frame, exhaust, or suspension part protected and looking good.

From The Driver Seat:
After the frame was rolled out of the curing oven, we were all amazed at the glistening, flawless finish. For added good looks and durable protection, it's hard to beat the powdercoating process.

PARTS USED:
Tubular frame, powdercoated DuPont Red Baron: $700
Headers and exhaust system, standard ceramic coating: $600
Custom gold/titanium exhaust system: $1,000
TOTAL: $2,300

The Players:
*Frame powdercoat painter: Martin Quezada
*Exhaust ceramic painter: Norberto Cabrerra
*Kelly Inman
*Keith Crecellus
*Lee Crecellus
*Larry Crecellus
*Rob Crecellus
*Hugh Randolph

SOURCE
Dupont Powdercoatings
www.dupont.com
Nordson Powdercoating
www.nordson.com
Nic industries Inc.
www.nicindustries.com
Specialized Powder Coatings
5862 Research Dr., Dept. CT
Huntington Beach
CA  92649
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