Powder coating can be an effective means to safeguard metal against corrosion, as well as conceal imperfections like hook marks, missed areas, Faraday areas, sanded spots or handling damage that compromise the finish and may require touch up work to fix. These imperfections may present problems for the finish itself and require professional touch up work in order to correct.
Metal fabricators, welders, machine shops and auto body shops must find fillers that can withstand the extreme temperatures associated with powder coating processes.
It is not a good idea
Powder coating is a cost-effective and long-term way to change the color of metal components, but its results can sometimes be uneven due to too thick of a coat or improper filler application.
Bondo, a popular putty, is not recommended as an additive in powder coating due to its inability to withstand the heat generated during powder application and cause outgassing and irregular finishes. Because of this, many custom coaters refuse any metal fabrication with layers of Bondo on it.
Higher temperature body fillers designed specifically to withstand the intense heat generated by powder coating processes are more costly than their Bondo counterparts, yet provide more consistent surface coverage and cure faster – examples being Thermobond-3 by Alvin Products or Lab Metal Epoxy Putty by them.
It can cause outgassing
Powder coating metal parts is an effective way of adding color, but it may lead to outgassing issues that lead to unsightly pinholes and craters in their finish, as well as leakage of moisture or contaminants during curing, creating pinholes or craters which allow water to seep into parts and cause corrosion.
One way to avoid this problem is to choose a powder coating filler with high temperature resistance – many powder coaters have turned to Thermobond-3 as their go-to product, though other alternatives exist as well.
Blooming, caused by poor resin or contamination on the substrate, can create an unattractive foggy or hazy appearance in powder coated products and is most visible with darker colors like blacks, dark blues and other darker hues. Blooming can result in expensive customer rejects; to reduce blooming altogether, eliminate contamination on your substrate as soon as possible.
It cannot be applied before a powder coat
Powder coating uses an inert polymer that doesn’t contain toxic solvents, making it much safer than liquid paint. Unfortunately, though, powder coating requires special equipment and may be prohibitively costly for smaller operations.
Powder coatings are applied to metal pieces using electrostatic force and baked in an oven, providing an efficient means of covering various surfaces and fabrications with this process. Once baked, the hard and durable finished product resists corrosion and abrasion for outdoor use – an excellent option!
Powder coating comes in many different hues and makes an excellent choice for industrial products as its colors won’t fade over time. Furthermore, its excellent moisture and heat protection means greater peace of mind for owners.
Powder coating should only be applied to brand new metal products for maximum effectiveness. Bondo filler could cause outgassing, leading to uneven finishing results; for best results, consider sanding or buffing to create a smooth surface instead.
It cannot be removed
Powder coating is an efficient metal finishing technique that keeps metals looking their best by covering them in an indestructible and corrosion-resistant layer of powder coating. However, sometimes things go awry during this process; for instance if the surface is rough or uneven it can be difficult to remove the powder coating and thus render your product unfinished and uneven in appearance. Luckily there are solutions to remedy such flaws!
Powder coaters frequently utilize plastic resin and two-part body fillers to repair parts that require powder coating, but these fillers do not adhere well with the powder, leading to defects during heat curing that require costly rejects.
Powder coaters have many options when it comes to stripping away old powder coating. Traditional chemical strippers may use harsh solvents like acetone and isopropyl alcohol; but plastic media blasting (PMB) offers another more environmentally-friendly option. Plastic media blasting uses recycled plastic media such as bottle caps to clean surfaces while simultaneously removing any previously applied coating – this process is safer and more sustainable than its chemical equivalents.