English 
English (US) 
German 
Danish 
Swedish 
French 
Polish 
Spanish 
Optimize Your Aluminum Weld Cleaning: Introducing the Electrolytic Method
Weld cleaning | Thursday, 12 September 2024
Thanks to its unique combination of characteristics and mechanical properties, such as strength-to-weight ratio, corrosion resistance, durability, and appearance, aluminum is widely used in many industries, including automotive, aerospace, shipbuilding, and general construction.
However, industrial professionals often face significant challenges during aluminum fabrication, particularly in all stages of the welding process—from preparation to surface cleaning.
Some of the main contributing factors to these challenges are porosity, high thermal conductivity, and the presence of a protective oxide layer on the aluminum surface.
Various methods are employed at each stage to ensure the finished product retains its aesthetic appeal and corrosion resistance.
So far, aluminum weld cleaning has traditionally been done using two methods: mechanical and chemical.
Both methods—chemical pickling and abrasive cleaning—come with their own sets of flaws, risks, and hazards. Chemical pickling involves the use of hydrofluoric acid, which poses serious health risks and requires costly disposal procedures.
Abrasive cleaning, while less hazardous, is less effective and produces dangerous airborne particles. These particles can be particularly harmful to the respiratory system and, along with other waste materials, may cause significant damage to the eyes and lead to lacerations on other parts of the body.
Today, we’ll introduce a viable alternative: electrolytic weld cleaning. This method offers a unique set of benefits, surpassing traditional methods in terms of process safety, simplicity, and convenience.
Below is a more detailed examination of the drawbacks associated with the two traditional methods:
An Overview of Conventional Aluminum Weld Cleaning Techniques
Mechanical and Manual Abrasion: This method involves removing visible contamination, dirt, oxidation, and slag from the weld area, or simply smoothing out the weld bead using electric tools and consumables such as wheels, wires, sanding discs, pads, grinding paper, flap discs, and others.
The choice between mechanical tools and manual methods depends on factors such as the level of contamination, the type and size of the weld, and available resources. However, this approach has several drawbacks: it is labor-intensive and slow, and it carries risks such as weld damage, cross-contamination, and other forms of structural distortion.
It is also associated with various health and safety risks, including particle inhalation and more serious injuries caused by waste, by-products, and the tools used.
Chemical Cleaning: Pickling paste is a commonly used solution for various types of weld cleaning, despite its notable drawbacks. While effective, this method requires stringent safety measures due to the harsh chemicals typically found in commercial products. Specifically, hydrofluoric acid (HF) and nitric acid (HNO₃) present significant health risks to operators, making them less ideal for widespread use.
Given these factors, it’s clear why expensive and highly regulated waste disposal measures are necessary. The extensive logistics and handling procedures further contribute to the complexity and costliness of this method.
You can read more about the dangers of this method here and here are 5 reasons to drop pickling paste now.
So, despite the well-known disadvantages of these methods, why are they still widely used?
A few of the reasons for sticking to traditional methods include resistance to change, their availability, and a lack of information about better alternatives.
Electrolytic Weld Cleaning: A Safer Way to Clean Aluminum Welds
Electrolytic weld cleaning operates on a simple concept: an electric current interacts with mild phosphorus-based fluids (acids) to create a chemical reaction that breaks down weld contamination.
The use of electrolysis in industrial production is not exactly new. However, it took decades of research and development to optimize this process for use in the final stages of metal fabrication, specifically welding.
The results Cougartron has achieved with stainless steel weld cleaning have been a breath of fresh air. From less-powered models to real powerhouses, we have developed machines that successfully remove all forms of contamination from various stainless weld types and sizes.
When compared to other methods, such as chemical pickling, special emphasis is placed on process safety, as the two techniques could not be more different in this regard. Unlike pickling paste, which is extremely dangerous due to its harsh chemical properties, electrolytic weld cleaning consumables are much safer, yet equally effective.
Aluminum weld cleaning comes with its own set of challenges. As the properties of aluminum and steel differ significantly, so do the welding and weld cleaning procedures used for each. However, the distinctive benefits of electrolytic weld cleaning remain the same.
Here are the major benefits of the electrolytic weld cleaning process:
- Safety: Electrolytic weld cleaning fluids/acids are mild and phosphorus-based, similar to those used in household cleaning products. When used properly, they pose no threat to your health or the environment.
- Simplicity: The fluids are easily applied onto the weld surface using a weld cleaning brush (automatic fluid feed is available). Some of our newer weld cleaning solutions are even more practical in this regard!
- Flexibility: The equipment can be used both on- and off-site, even on tall structures and hard-to-reach areas. Minimal PPE is required, and no complicated wastewater disposal procedure is necessary.
- Ease of Use: Even if you are a total beginner, you can start using Cougartron equipment after a quick demonstration.
- Speed: With the right setup, you can clean even the most demanding welds in no time.
Aluminium Weld Cleaning and the Electrolytic Method: Keys to Success
As with many industrial processes, cleaning aluminum welds rarely succeeds with a one-size-fits-all approach. This is due to the numerous factors involved, including aluminum alloy series, weld type, level of contamination, thickness, construction type, and more.
When it comes to Cougartron equipment, our team of experts offers a few key guidelines to follow.
- Aluminum Alloy Series: There are seven commercial aluminum alloy series, each with distinct properties and applications based on purity and metal composition. Our equipment currently handles the following series:
– 4000 Series (aluminum and silicon): Used in the automotive industry and as a filler material during welding.
– 5000 Series (aluminum and magnesium): Commonly used in trailers, tanks, and bridges.
– 6000 Series (aluminum, magnesium, and silicon): Ideal for construction, structural, and supporting elements.
- Machine Model: We recommend using our medium to high-powered machine models (30–200 amps) that allow precise control of power output, adjustable according to the level of contamination. This includes nearly our entire range of machines, from the Power30 to the FURY200XF, as well as the Cougartron ProPlus, which has a proven track record in aluminum weld cleaning. Please note that, due to the specific characteristics of aluminum, applying higher amperage to less-contaminated welds can be counterproductive and is not recommended.
- Weld Type: Both TIG and MIG welds can be cleaned effectively, provided all other conditions are met. Since properly welded TIG welds often require no special attention, Cougartron equipment is most beneficial when used for aluminum MIG weld cleaning.
- Weld Thickness: The effectiveness of cleaning can vary with weld thickness. Generally, our equipment is versatile and can handle various thicknesses, but specific adjustments may be necessary depending on the exact measurements.
In general, you can expect consistent result on base metal surfaces up to 1″ (2,54cm) thick. Naturally, this greatly depends on the machine model where the process outcome depends on its potency. Here are some rules of thumb regarding our equipment and aluminum thicknesses:
– FURY200 and FURY200XF: Up to 1″ (2,54cm)
– Power30 and Power30X (combined with the FL20 fluid feed): Up to 3/16″ (0,5cm)
– ProPlus: 5/16″ (0,79cm) to 3/8″ (0,95cm)
– FURY100 and FURY100XF: 1/2″ (1,27cm) to 5/8″ (1.58cm)
- Consumables – In most cases, satisfactory results can be achieved using the CGT-350 weld cleaning fluid (or an equivalent amount of fluid made with CGT-650 powder). It contains a suitable (lower) concentration of phosphorus suitable for this type of work.
These are general guidelines, but we always recommend contacting one of our team members for advice. We are always ready to help.
Aluminum Weld Cleaning – The Process
Follow these steps for optimal results with your process:
Before you start:
- Ensure your machine is properly connected (consult your user manual if needed).
- Prepare your consumables: brush(es), weld cleaning fluid, and neutralizing fluid.
- Assemble your brush: Attach the brush to the wand.
- Connect the earth clamp to the workpiece.
- Turn on your machine.
- Choose the correct setting: AC mode is recommended, combined with lower amperage where possible. The DC mode is primarily used for polishing and comes with its own set of guidelines.
The weld cleaning process:
- Dip your brush into the fluid container (or use the automatic fluid feed if available).
- Apply the fluid to the weld area using the brush. Take your time, as aluminum weld cleaning is a delicate process.
- Wipe the fluid off the surface after cleaning each foot (30 cm). Don’t let the cleaning fluid sit on the surface.
- Apply the neutralizing fluid (CGT-N5) immediately after cleaning.
- After a minute, wipe the neutralizer off the surface with a clean paper towel, and you’re done!
Please note: Some steps may vary depending on specific production requirements. It’s important to consult with our team to ensure you receive proper guidance.
Bonus Tip on Aluminum Weld Preparation – Use CGT-N5 and Wipe ‘N’ Weld for Better and Safer Results
Proper preparation of metal surfaces before welding is crucial for achieving strong and healthy welds. This is particularly important in aluminum welding, where the preparation process involves several stages, including thorough surface cleaning. Traditionally, acetone has been used for this purpose due to its low price and effectiveness in removing various contaminants. However, this is a highly flammable solvent and requires careful handling to avoid potential hazards.
Cougartron offers safe and effective alternatives for pre-welding preparation: CGT-N5 neutralizer and Wipe ‘N’ Weld specialized cleaning wipes.
CGT-N5 features a high-performance formula that acts as both a neutralizing and degreasing fluid. It also includes desiccants, making it an ideal non-flammable and quick-drying solution for weld joint pre-cleaning. CGT-N5 provides all the benefits of acetone but in a safer manner and can be applied in just a few simple steps.
Wipe ‘N’ Weld wipes effectively remove oil, grease, water-based paints, permanent markers, dirt, grime, and fingerprints from various metal surfaces, including aluminum. They ensure the surface is clean and dry, leading to an improved welding process with fewer headaches.
>> CLICK TO LEARN MORE ABOUT WIPE ‘N’ WELD <<
Are you Ready to Improve Your Aluminum Weld Cleaning?
If you’re seeking a safer and more efficient way to clean aluminum welds while avoiding the harmful consequences of traditional methods, look no further.
Feel free to reach out with any questions or concerns—our team is always happy to help, with no strings attached.
We also offer both in-person and online demonstrations for your maximum convenience.