The Ultimate Guide To Chrome Plating
Again, just don't do chrome plating on your own. The risks are simply not worth it. Plus, you have an excellent alternative with PChrome spray chrome, which can give you the same durability and look as chrome plating but without all of the associated dangers, expense and time.
Author: Anna
What Is Chrome?
Chrome, short for chromium, is a naturally occurring metallic element. While it can exist in solid form, its primary utility lies in its application as a plating material. A thin layer of chrome is often applied to various surfaces, including steel, brass, aluminum, plastic, copper, and stainless steel, to enhance their appearance and durability.
It's important to note that some people mistakenly refer to all shiny finishes as chrome, even when they don't contain chromium. Alternatives that may be considered “chrome-like” include highly polished aluminum, vacuum-metalized mylar, painted wheels, and nickel-plated items. However, true chrome plating is characterized by its brighter, bluer hue and deeper reflective quality compared to other finishes.
This guide will provide insights into the chrome plating process and explore some alternatives.
Guide to Chrome Plating
You may have come across various terms related to manufacturer of powerline accessories, such as chrome electroplating, chrome dipping, and chroming. Generally, these terms refer to the process of chrome electroplating.
Is All Chrome Plating the Same?
Chrome plating can be categorized into two main types: engineered chrome plating and decorative chrome plating.
1. Hard Chrome or Engineered Chrome Plating
Many people are unfamiliar with hard chrome or engineered chrome plating. This process involves applying a thick coating designed to enhance lubricity, oil retention, wear resistance, and overall durability. Hard chrome is commonly used on components such as piston rings, thread guides, mold surfaces, and hydraulic cylinder rods. It is termed "hard" because it has sufficient thickness to be measurable, in contrast to decorative chrome plating, which is only a millionth of an inch thick and cannot withstand hardness testing.
Hard chrome plating is typically applied to steel surfaces, resulting in a shiny, metallic finish that is not intended for decorative purposes. It is an excellent choice for functional components like bumpers and wheels. There are variations of engineered chrome plating, including some that are optimized for porosity to retain oil and others that are thinner.
Companies specializing in engineered chrome plating usually do not offer other types of plating. Most customers seeking hard chrome services are not likely to be interested in businesses that focus exclusively on this process.
2. Decorative Chrome Plating
Decorative chrome plating, often referred to as nickel-chrome plating, involves an initial electroplating of nickel onto the part before applying the chrome layer. In some cases, copper may be electroplated instead of nickel. The nickel or copper layer provides smoothness, corrosion resistance, and reflectivity. The chrome layer added on top is very thin, measured in millionths of an inch.
When you observe a nickel-chrome plated surface, you are primarily seeing the effects of the nickel plating. The thin chrome layer imparts a subtle bluish hue, enhances protection against tarnishing and scratching, and contributes to overall corrosion resistance.
Why the Quality of Chrome Plating is Critical
The quality of chrome plating is essential for ensuring durability and performance. Using low-quality chrome plating can lead to porosity or pinholes in the finished product, resulting in worse outcomes than if no plating was applied at all. This is because the underlying steel is left exposed and prone to rust. If you notice tiny rust spots on a product upon purchase, it indicates a defect, and the item should be returned.
Common Terms: Show Chrome, Triple-Chrome Plating, and Double Nickel-Chrome
The term "show chrome" refers to high-quality chrome plating suitable for vehicles entered in car shows. Chrome enthusiasts believe that applying a copper layer first, followed by thorough buffing to achieve a high sheen before the nickel plating, is key to achieving a quality finish. Typically, high-quality plating involves applying two layers of nickel before the chrome layer.
Salespeople often use terms like "triple-chrome plating" to suggest that there are three layers of any type of plating. However, this terminology is often more about marketing than substance.
For durable chrome plating designed for outdoor exposure, it is crucial to have at least two layers of nickel plating beneath the chrome. The process should include a layer of semi-bright nickel followed by a layer of bright nickel. This configuration improves corrosion resistance because the bright nickel acts anodically to the semi-bright nickel. Chrysler has developed a test used by many large shops to ensure that the chrome plating meets the required protection standards. Restoration shops that offer only single-layer nickel plating must apply it in significantly heavier layers to ensure adequate corrosion resistance.
Restoration Work
Chrome plating is a lengthy and intricate process that begins with buffing, polishing, and cleaning, followed by dipping in acid and applying zinc and copper plating. For show chrome, the procedure continues with re-buffing, cleaning, re-dipping, and applying additional layers of copper and two to three types of nickel plating, culminating in the final chrome plating. Each step involves rinsing the item to ensure a quality finish.
Re-chroming a part requires the removal of the old chrome, nickel, and copper layers. The part is then polished to eliminate blemishes and scratches before applying copper plating. This is followed by buffing to fill tiny pits with copper, and then the aforementioned steps are repeated.
As a result, re-plating an old piece can be several times more expensive than purchasing a replacement part. New items demand less preparation, and machines can process dozens of identical parts simultaneously, while old parts must be handled individually.
When Chrome Blisters or Peels
Chrome plating that blisters or peels is typically indicative of a manufacturing defect, often due to poor adhesion of the chrome plating to the surface. Chrome-plating shops frequently struggle to achieve good adhesion on certain materials, such as alloy wheels.
If your chrome begins to peel, it is advisable to file a complaint rather than accept excuses from the shop about chemicals or washing frequency affecting the plating.
Do It Yourself?
Chrome plating should only be performed by professionals in a regulated shop environment. The process involves hazardous toxic acid baths, and the electroplating industry is one of the most stringently regulated due to the environmental impact of the waste produced.
Attempting a DIY chrome plating project can easily lead to violations of Environmental Protection Agency regulations. The numerous regulations can be overwhelming, and disposing of waste, including any diluted water used in the process, can pose significant challenges. You remain liable for any environmental damage caused by the waste, even if you manage to find a disposal facility. Therefore, it is strongly recommended to leave chrome plating to the experts.
Chromic Acid
Chrome plating involves the use of highly concentrated chromic acid, the same toxic chemical that gained notoriety from the Erin Brockovich case. If you were to handle this substance and someone nearby subsequently developed cancer, you could potentially face legal repercussions. Facilities utilizing chromic acid are required to implement exhaust scrubbing systems and undergo daily monitoring to ensure safety standards are met. Additionally, workers must frequently undergo blood tests to check for chromium absorption.
Chromic acid has a tendency to leach into the ground and contaminate aquifers, becoming detectable at concentrations as low as 1 part per million. Consequently, all water supplies and wells are regularly monitored for this hazardous chemical, making illegal disposal highly risky and likely to result in detection.
Hydrogen Embrittlement of Steel
Many municipalities have enacted bans on chrome plating due to its potential for hydrogen embrittlement, a phenomenon that can render hardened steel parts brittle and glass-like. Furthermore, numerous city councils have established formal or informal prohibitions against chrome plating, further limiting its use.
Again, just don't do chrome plating on your own. The risks are simply not worth it. Plus, you have an excellent alternative with PChrome spray chrome, which can give you the same durability and look as chrome plating but without all of the associated dangers, expense and time.
