The combination of proven welding equipment, experience and skills is the key to a successful welding project. Everybody wants higher productivity and lower cost, but safety comes first, so a welding helmet as personal protective equipment is a must. However, metalworkers and seasoned welders know that welding is more than just laying the bead to adjoin the metal pieces to get the final product.
An integral part of welding is preparation and finishing and it’s important to make sure the operators use their grinding and sanding equipment with safety precautions. To increase safety and get the job done right, you need to use the correct sanding discs. To help you choose right, here is all you need to know about them and how to select the most suitable sanding disc to give your welds a smooth finish.
What Are Sanding Discs Used for?
When the process of welding a joint is done, it’s time to grind the weld down using an angle grinder and an abrasive disc. The angle grinder is often used to create bevelled edges in the preparation of the welded joint. Also, it can be used for removing contaminants from the metal’s surface to ensure a contamination-free weld.
When it comes to sanding discs, you can choose from a variety of options on the market. However, it can be an overwhelming task as there is a wide range of different discs, grains and grits. To find the most suitable sanding disc for your project, consider the type of abrasive materials the tool is made from.
Ceramic abrasive grain usually comes in red colour and is the top choice in terms of effective cutting ability and the long-lasting of the discs. It’s sharp, tough and long-wearing, therefore excellent for aggressive material removal with various types of metal, including stainless steel. A ceramic sanding disc is a great solution for removing stock and sanding surfaces in metal. This type of sanding discs is more popular in more coarse grits.
Zirconia is blue or green, suitable for use on all materials, from wood to fibreglass, metal, brass aluminium and stainless steel. This is a long-lasting grain, perfect for grinding away burrs on metal. Sanding metal with zirconia alumina can make the grit particles sharper, meaning that you won’t have to change sandpaper so often.
Aluminium oxide is a durable synthetic grill and a good choice for sanding and polishing different types of metal, including alloy steel, bronze and more, but it’s not suitable for stainless steel, though. Aluminium oxide is generally brown.
Types of Sanding Discs
Every professional wants to perform a perfect job and when it comes to angle grinders, most welders prefer paddle trigger models over switches as they are safer if your hands move from the grinder. But angle grinders can be modified to take many different types of abrasive discs, cut off wheels and even polishing discs, which is another reason why they are so popular.
Same as many sanding discs on the market, angle grinders are available in a few different types and the following are the most commonly used ones.
Resin Fibre Discs
These are generally used for blending, grinding, deburring and finishing metals. They are used on an angle grinder with an appropriate backing pad and are abrasive and heavy-duty, manufactured for a range of applications, from surface blending to heavy stock removal. The chances of errors and breakage are reduced thanks to the sturdy fibre backing that adds strength to the disc and ensures it remains rigid when in use.
Some of the most popular resin fibre discs are the ones that feature a hole in their centre for mounting and are used on electric or air right angle grinders. Resin fibre discs are the best choice if you need to remove rust and burrs from different metals, including steel. Compared to other types of sanding discs, resin fibre discs are a cost-effective alternative, available in different sizes, materials and grits, which makes them a great choice for various applications.
Flap discs are an innovative grinding wheel using coated abrasives, which offers more versatility on the product and a softer grind. This type of discs is used on an angle grinder available in many different sizes, grits and materials.
Flap discs are one of the most popular abrasives among welders due to their ability to give the welds a nice, smooth finish, remove mill scale, rust and aggressive stock removal. These discs are made up of little pieces of sandpaper that are fixed to a firm backing. The multiple pieces of sandpaper increase the effectiveness and the durability of the discs.
They are a good choice for polishing metal or removing rust from it and are ideal for aluminium, steel and other types of metal. If you’re looking for a resilient choice to polish or sand metal surfaces, flap discs and their sturdy composition might be your best choice.
Hook and Loop Discs
These are made up of cloth or paper with a backing material similar to Velcro. With a system of hooks and loops used to affix the sanding disc to the sander, it’s very easy to change the disc with no need to sacrifice the quality of the disc you use.