Frequently Asked Questions about Powder Coating:

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1 Frequently Asked Questions about Powder Coating: Q: What is Powder Coating? A: The application of charged particles (essentially pulverized plastic) to a grounded surface (typically metal). The parts are then baked to flow out the powder and bond it to the surface. Q: How Durable is the Powder Coated Finish? A: The durability of the powder coating finish is determined by the type of powder used, thoroughness of the surface prep and proper cure. The powders we sell offer the best combination of solvent and UV resistance. Powder should only be applied to clear bare metal. Properly prepped and cured, powder will with stand impacts hard enough to dent the surface without chipping the powder. The powder coating finishes Eastwood sells are far more durable than the best liquid coatings. Q: What Parts Can be Powder Coated? A: Any metallic parts that withstand the 400-degree F cure and can physically fit in your curing oven. Q: Can I Use a Common Kitchen Oven to Cure Powder? A: Electric kitchen ovens, even toaster ovens can be used to cure powder. The size of the oven is obviously what limits the size of the part you can cure. The oven used for curing powder should be dedicated to that purpose and never used for cooking. Q: Why shouldn t I cure powder in the same oven food is prepared in? A: If some residual powder remains in the oven it will produce toxic fumes that will contaminate food. 263 Shoemaker Road, Pottstown, PA Page 1

2 Q: Can I use a toaster oven to cure small powder coated parts? A: Parts small enough to fit in a toaster oven like master cylinder lids, wheel cylinders, etc. can be easily cured. Do not use the toaster oven for food products after using it to cure powdered parts. Q: Can I cure the powder in a gas oven? NO! Why? A: Commercial powder coating companies use special gas ovens with no exposed flames or electric powdered ovens for curing. Ordinary gas ovens have exposed flames. We recommend electric ONLY to lessen the possibility of powder flare up. Q: What can cause pitting in the cured powder finish? A: Impurities on the surface erupting during cure, too light or too heavy a powder application or contaminants in the powder. Q: Powder coating can be easily applied to edges and outside corners. Why is it difficult to apply powder to inside corners and deep recesses? A: Faraday Cage Effect is to blame for the difficulty encountered when trying to apply powder to recessed areas. There is actually a buildup of electrical charge that repels the charged particles of powder. To get these areas to coat, instead of aiming the gun directly at the part, make a pass with the nozzle parallel to the surface and work quickly. Q: What prevents the applied powder from falling off? A: As the powder flows through the nozzle of the gun it picks up a charge. The charged powder clings to the grounded part by static charge. 263 Shoemaker Road, Pottstown, PA Page 2

3 Q: The coating easily chips. What went wrong? A: Easy chipping is an indication of surface contamination or incomplete curing. Try baking the part for an additional 20 minutes at 400 degree F. If this doesn t help, the coating will need to be removed with our Powder Coating & Paint Dissolver (12849, Qt or 12850, Gal), thoroughly cleaned and recoated. Q: How thick should powder be applied to achieve good flow out? A: Stop as soon as the surface is uniformly opaque with the powder. Q: How thick is a mil in inches? A: A mil is about.001 or 1 thousandth of an inch. The properly powder coated surface has between 1.5 and 3 mils. Q: How can orange peel be minimized? A: Orange peel is the appearance of little tiny holes in the finish. Be sure surface is uniformly covered and powdered part is put in an oven that is already up to temperature. Leave the part in for the full 20-minute cure after flow-out. Make sure the oven has been preheated to the correct cure temperature. Q: Can the cured powder be polished to remove orange peel and scratches? A: The powder coated surface can be treated much like a painted surface. Powder can be easily sanded with 600 grit wet or dry paper and buffed to a high shine with automotive compounds. 263 Shoemaker Road, Pottstown, PA Page 3

4 Q: What is the maximum cure time that can be used without damaging the powder? A: Heavier parts such as castings may require additional cure time to achieve proper flow out. Longer cure times will not harm powder. However higher temperatures will. Q: What are the maximum service temperatures? A: Powder coated parts should not be subjected to temperatures in excess of 350 degrees F as the coating will be damaged and burned away. Exhaust manifolds and headers can reach over 500 degrees F. Therefore powder coating is not suitable for this application. Q: Why will Hi Temp Lab Metal (10288Z) work under powder when most other body fillers will not? A: Hi Temp Lab Metal can hold a charge and attract the powder like the surrounding metal. It can withstand the cure temperature required for powder curing. (The filler should not exceed 1/8 thick.) Q: What causes poor adhesion of the powder to the surface? A: The part must be thoroughly cleaned (Metal Wash or PRE Painting Prep 10041Z) work well here. Wear disposable gloves like our Nitrile Gloves (43098, M, L or XL) to prevent contaminating the parts. Hold the gun about 4-6 from the surface to be coated and move the nozzle in a circular motion to keep the powder flowing efficiently and coat the surface evenly. 263 Shoemaker Road, Pottstown, PA Page 4

5 Q: Can powder be used over Aluminum and Magnesium? A: Yes, Special prep however may be needed to thoroughly clean the surface before coating. Pre-baking at 400 degrees F is required to drive out contaminants from the pores of the metal. (Bake for at least 30 minutes.) Q: How do you mask parts for powder coating? A: There are often areas where powder build up is not desirable. Masking critical tolerance areas such as threads and holes can be done with Hi Temperature Silicone Caps and Plugs (10078 or 58041), Hi Temperature Fiberglass Masking Tape (10027, ½ or 10115, 1 ), aluminum foil, or by brushing away powder before curing. Hi Temperature Silicone Plugs (10078 or 58041) plug threaded or critical tolerance holes and can also be used as feet to support the part for coating and curing. Hi Temperature Fiberglass Tape (10027) is used to protect external threads/other critical areas where powder deposit is not desirable. This tape is superior to masking tape because it doesn t leave a gooey residue and provides a finer parting line. Common aluminum foil is great for quickly masking large sections. Before curing deposited powder can be brushed away with a soft camel hair or comparable brush. Brush thoroughly to remove all traces of powder. Q: What is the function of the Deflector and where should it be positioned? A: The deflector enables the powder to be spread over a larger area. For smaller or more intricate surfaces the deflector can be removed. 263 Shoemaker Road, Pottstown, PA Page 5

6 Q: What is the easiest way to suspend parts for coating and curing? A: In many cases the easiest way to support parts for coating and curing is to hang the part (using uncoated wire like our Stainless Steel Safety Wire # or # Powder Coating Hooks) right from the oven rack. The Rack can be easily clamped to a sturdy table edge or help between sawhorses. Do Not hold the part in your hand while applying powder! Q: Can cured powder be touched up with liquid paints? A: Yes, powder coating can be easily touched up with enamel paints. In many cases our 1-Shot Lettering Enamels are a very close match. Q: How can I remove cured powder if I don t like the results? A: Abrasive blasting and other mechanical means are time consuming. The most effective way to remove cured powder coating is with our Powder Coating & Paint Dissolver (12849, Qt or 12850, Gal). 263 Shoemaker Road, Pottstown, PA Page 6