For every success story about powder coating on wood there is a chorus of companies that were disappointed. You will hear statements such as: "Too expensive," or "not flexible enough," or "it just doesn't work."
So how is it that some companies have outstanding results while others are disappointed?
The short answer is that every technology has its limits - if you're driving in a screw you can't expect optimum results using a hammer. The long answer is that powder coating on wood is not a simple technology to implement.
A successful operation requires much more than just equipment. Companies must be prepared to analyze their costs, including those not usually considered, they must have realistic expectations - both short and long-term - and they must balance this with the benefits of powder coating and how it can contribute to increased productivity and higher sales.
Can your company successfully implement powder coating on wood technology? It may depend on where you fall in the production spectrum. On one end there are the companies seeking to replace current multi-step finishing lines, or develop new products not possible using traditional finishing or vinyl wrap methods. In most cases, the qualified answer would be "yes."
On the other end are those companies with relatively fewer production steps. Whether painting or vinyl wrapping, they are efficient and profitable at producing short runs of square-edged pieces. Here, powder coating on wood would most likely be a "no."
For those medium-size companies with substantial production runs, environmental concerns, or a desire to achieve a particular surface finish, "maybe" is the only realistic answer.
Company size, by itself, is only one determining factor. The key is to think of powder coating as an investment in the future - not just future production capacity, but future design capability.
Powder coating's strength is its ability to provide a uniform surface finish on almost any part - curves, shapes, and even flat surfaces with compound radius edges - and select from an almost infinite number of colors and a wide choice of surface finishes. This capability can open up a spectrum of new product designs. In a competitive market, those new products could be highly profitable, even in shorter runs.
As with any new technology, you must make certain that it is right for your application and that all vendors have a full understanding of your expectations. The key word here is understanding. Once you understand the technology and what it can do, you are in a position to evaluate suppliers and make informed decisions.
Keep in mind that powder coating on wood is not just a new technology. It is an emerging technology. New powders, new techniques and new systems are in the testing stage right now that could dramatically increase the beneficial impact of installing a powder-on-wood system in your facility. To find out more about what is coming in the near future, contact experts in both powder manufacturing and powder-on-wood systems design and construction.
The process itself is critical to evaluating the feasibility of powder coating on wood technology. Currently, powder coating is only suitable for application onto MDF. The reason has to do with its relatively uniform structure and consistent moisture content. While different types of wood used in MDF can exhibit different relative humidity levels, there is very little variation in any given lot. It is this moisture content that provides the key to a successful application.
In a typical operation, the shaped MDF board is preheated in an oven to force the moisture to the surface of the board. When the board moves into the powder application zone, the surface moisture attracts the powder. As the powder builds, it attracts even more powder. Then the board moves into the curing oven where the coating flows out, producing a mechanical bond with the surface.
Oven temperatures are critical both in the flow out stage and in the curing process. These temperatures, plus the duration in each zone are determined by the board's shape, its relative humidity, the powder formulation properties and the thickness of the coating. Once the powder coating has set, the board must move into a cool-down zone to reduce its temperature prior to being stacked and wrapped for shipment.
Given the complexity of the process and the critical variables, it is important that you maintain realistic goals. Installing a powder coating on wood line is not like purchasing a piece of CNC equipment and plugging it in. This is why it is important to select an equipment builder with experience in powder coating. The experienced company will be able to design and build a system that can function properly, but may take time to fine-tune the equipment in order to achieve optimum results in your facility.
A close partnership between the customer, the coating material supplier and the equipment builder results in a successful powder coating system. The computer programmer's expression "garbage in, garbage out" also holds true when designing a powder coating on wood system.
The more information you can provide, the easier it is for your suppliers to meet your expectations. Some of the information is fairly obvious, such as material and finish specifications. Other data, such as production rates, require a thorough analysis of your current operation, and projections or goals for the future.
One of the difficulties in projecting your future requirements is the lack of sufficient hard numbers. Paint has been around almost forever. Laminates and vinyl have a long history of success. Their material capabilities and production parameters are well known. As a result, costs and production requirements can be accurately calculated and projected. But wood powder coating is an emerging technology with its own set of production variables. In a very real sense, you will be generating your own data - and proprietary data at that - as you go.
Determining what factors to consider, what to measure and what data to generate is the key to a successful powder coating operation. In many cases, the direct benefits of powder coating will be obvious (i.e. the ability to coat an infinite variety of shapes) and measurable in potential sales increases. But in other cases indirect benefits, such as reduced labor, that can significantly reduce overall costs are more difficult to measure. Knowing what to measure will help you generate an accurate picture of your return on investment.
One method of overcoming the initial lack of hard data is to use your current production rate with whatever process you have now as a benchmark. Then project that rate five years into the future. This will help the equipment builder understand what must go into your system in order to meet current production needs and accommodate future expansion.
If, for example, you project your production volume to double in five years, the equipment builder should design the conveyor system for that maximum throughput, but size the ovens, application zone and cool-down zone for current requirements. Since most of the equipment is (or should be) modular, it is a relatively simple process to add capacity incrementally.
Getting started requires a meaningful investigation of powder coating on wood and is a two-step process. First you must discuss your needs and expectations with the powder coating material supplier. Once you have selected a particular powder coating or range of coatings, initiate discussions with an equipment builder.
The equipment builder often can help you find a material supplier, but you are ultimately responsible for the selection. The reason for this is not to be able to point fingers if something doesn't work. Virtually every aspect of a system's design is driven by the powder's properties, and each powder has its own unique chemistry.
When you speak with a powder manufacturer you should provide as much information as possible about your application, including the manufacturer of the board, the board specifications, thickness, moisture content, etc. Next, the powder supplier will want to know the mil thickness of the finished coating and what look you want: gloss, satin, pebbled, etc. You also should discuss the end use of the product. Powder coatings for a work surface may have entirely different properties than one for a kitchen cabinet door.
Once you have the powder material specifications and properties, your equipment builder will use that information to determine the critical elements at the various stages. You also should provide information about your finished piece size or sizes and production volumes.
Again, you will need to supply information about both your current and projected requirements and the required line speed. This will help the equipment builder determine the system's parameters, including the type and length of conveyor system, the size and length of the pre-heat, curing and cool-down zones, and the type of powder application equipment.
At this point, you will have a general idea about the scope of your proposed system and a good indication of whether or not powder coating on wood is right for you.
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