It's possible that you want the aluminum bicycle pedals you're having custom-made to be a gorgeous shade of blue, or that you want the threaded fasteners you're having turned to be more durable. These are just a few examples of the many ways in which we can help you improve the performance of CNC machined parts and sheet metal parts, make them more resistant to wear and corrosion, and improve the appearance of the parts as a whole by using a variety of finishing options. Plating can be applied to a variety of different materials. Nickel plating is the solution for those of you who are looking for a finish that is resistant to corrosion and wear, is long-lasting, and can be applied to a wide range of different materials. Here at Protolabs, we offer the two that are most frequently used. The first of these processes, known as bright nickel plating, is carried out by applying a negative charge to a workpiece following its immersion in an electrolyte tank. Bright nickel has a lustrous appearance, as its name suggests (0.00005 in. to 0.0254mm). There is a good chance that the bumper on your old car, as well as the trim pieces on the dashboard, and the lighting fixtures in your home are all nickel-plated.
 

The use of electroless nickel plating removes the necessity of making electrical contact, as well as the subsequent electrical flow that was described. As a result of this, it is a popular choice for the plating of high volumes of fasteners, fittings, and other types of hardware items. Because it plates evenly all over the part, it is also very useful for reaching interior areas that are difficult to access. Various Options for Plating Including Zinc, Tin, Gold, and SilverThe electroplating method that was just detailed is adaptable to use with a variety of different metals. If, for example, you remove the nickel anodes and replace them with zinc anodes, you will be left with a plating that is very effective at preventing iron and steel from corroding. Additional information can be found in the document labeled "zinc coating ASTM B633-15."Tin plating is also quite common because of its relatively low price. Because it is not only resistant to corrosion but also quite agreeable to soldering, it is frequently used in the electronic industry for the construction of computer chassis and other components due to its softness, ductility, and silvery-white coloration.

It is also possible to use hot dip tin plating, which, along with the alternative of having it electroplated, is described in MIL-T-10727 (MIL is an abbreviation for "military specification coating"). Both of these metals are comparable to tin from the point of view of the electronic industry; however, they have increased conductivity, solderability, and resistance to corrosion, and their prices reflect these improvements. In addition, as is clear from the fact that they are used in the jewelry and dinnerware industries, they have an appealing physical appearance. Because nickel plating has such good adhesion properties, it is frequently used as an "undercoat" for other coatings before they are applied. In spite of the fact that it is technically an electrochemical conversion process, this procedure is frequently referred to as a plating operation. It involves applying a very thin oxide film to the surface of a metal part. Anodizing of titanium and other metals is also possible, but for the purposes of this discussion, we will concentrate on the process of anodizing aluminum in accordance with the standard MIL-A-8625. There are three different ways that aluminum can be anodized. Chromic acid anodize, type I, produces a coating that is imperceptibly thin but remarkably long-lasting.

The typical thickness of this coating is between 0

- 00127 and 0

- 00254 millimeters

- Priming material for painted surfaces and welded assemblies are two common applications for this substance

- Non-conductivity is a property shared by all anodized surfaces

- Anodizing in Type II Sulfuric Acid, which is also known as decorative anodizing due to its capacity to absorb virtually any color dye, is an even more difficult process

- Having said that, it provides a finish that is exceptionally long-lasting and up to 0

- 0254mm) thick, which is also quite appealing

- The next step up is the Type III Hard Anodize, also known as the Hardcoat

- 003 in

- As was previously mentioned, another possibility involves anodizing the titanium components

- If you require any further clarification, please refer to the standard Aerospace Material Specifications (AMS), in particular AMS 2487 and AMS 2488

- Titanium components used in aerospace applications are often anodized to increase the material's resistance to corrosion

- In order to bring this discussion on custom cnc milling and plating to a close, I would like to briefly mention the use of military (MIL) and aerospace (AMS) standards throughout the course of this conversation

- When placing an order with us, it is in your best interest to make reference to these and any other applicable specifications, if they are available; otherwise, we may be left wondering what kind of anodizing, etc

is being used. The following table provides an overview of the three distinct approaches to custom cnc milling aluminum that are available. Keep in MindSealing After AnodizingParts are typically sealed in a bath of nickel acetate or hot deionized water immediately after the custom cnc milling process, with a few notable exceptions. This procedure closes off the microscopic pores of the material. Before moving forward with the process, make sure to have a conversation about the application requirements for mission-critical parts with one of our applications engineers. Consider it to be a dry paint that can be applied to any electrically conductive metal; it is a standard component utilized by sheet metal fabricators such as Protolabs. This method involves spraying a colored powder that is based on a polymer through a specialized gun that charges the individual paint particles as they pass, causing them to adhere to the surface they are passing over. It is also better for the environment because any powder that is left over can be reclaimed and used again, and there are no odorous VOCs (volatile organic compounds) to contend with like there are when using paint.

Paint is an excellent alternative to powder coat for components that either cannot withstand the heat generated during the curing process or that require a coating that is thinner than what is offered by powder coat. In either scenario, you can select from dozens of different colors and sheens from our inventory. In most cases, color matching is not available; however, if you are purchasing paint from us, we may be able to color match. Please take note that color matching for injection-molded parts is a service that we do offer.