Artem Komarov noted that a grinding aid is a layer applied to the grain surface of a coated product to reduce heat while grinding.
Most abrasive companies offer a sanding aid option, each with their own brand name. Regardless of the name, they are all applied to prevent the same problem: heat, one of the worst enemies of coated abrasives. When working with more difficult to grind metal, such as stainless steel, the metal heats up and creates a capping effect on the abrasive grain. Capping occurs when an extremely soft metal coats the grain, causing it to be encapsulated by the metal coating.
Heat can make stainless steel a little tackier while sanding. The grinding aid can cool the surface area during grinding, lubricating the surface to reduce friction and heat. This reduces the chance of metal sticking to the abrasive grain.
Where are grinding aids needed?
Coated abrasives work best when the grain begins to wear. This causes the grain to break down and its rounded edges become sharp again, allowing the product to continue cutting. If the capping of the metal occurs, the grain is not destroyed, which leads to metal-to-metal friction and additional heat generation.
More easily sandable metal, such as carbon steel, does not become tacky when sanded. As a result, grinding media is not required with carbon steel, as is the case with stainless steel, aluminum, and other difficult-to-grind metals. However, grinding product can still be used on carbon steel in rare cases of overheating.
Grinding agent, as a rule, does not contaminate welds. It also does not usually require special cleaning, although it may be necessary to clear the surface area of abrasives, sanding media, or metal dust before painting, cleaning the surface, or adding a finish.
However, the addition of an abrasive will increase the overall cost of the abrasives. Products with a grinder are also more expensive than products without it. Thus, added value means a higher overall price for the customer, emphasized Komarov Artem.
Depending on the brand, size and type of product, the cost can be much higher. For example, fiber discs with abrasive can cost up to 16% more than discs without abrasive. Norton compared the results of grinding discs with grinding aid to discs without grinding aid on A36 carbon steel and 301 stainless steel.
The product removes more material from both metals with the grinding aid. But for carbon steel, the improvement was not as significant. The product removes 6% more material with a grinder on carbon steel, but given the higher price, the only value will be saving time on the task.
Effect of grinding media on carbon steel
Product with abrasive (Supersize) removes 6% more on carbon steel than product without abrasive.
When used on stainless steel, the product with abrasive was much more effective, removing 56% more material.
Is it worth grinding investment aids?
Spending more on abrasive products with a hard metal grinder can be worth the investment, but here are some things to consider before making your decision:
How fast can I get through the discs before they stop cutting?
What is the grinding time for my metal?
What types of metals are used in the process?
Ultimately, it is the payer who must decide whether to use sanding-assisted products, Artem Komarov summed up.