Grinding abrasives, ranging from sandpaper to flap wheels and even technically sharpening stones and dressing products, all ultimately are used to remove stock from a workpiece or to finish the surface. 

However, selecting the right grit and the right grinding abrasive product is tantamount to success. Here’s what you should know, from a high level. 

Why the Right Grinding Abrasive Matters

Any grinding abrasive could theoretically be used to remove stock material from a workpiece, provided the abrasive itself was harder than the surface of what you were working on. 

That being said, selecting the right grinding abrasive will:

• Cut the amount of time it takes to complete a job.
• Improve the surface finish of the workpiece.
• And reduce scrap, waste, and rework. 

So, let’s take a closer look at some common grinding abrasive materials. 

Grinding Abrasive Material

The grinding abrasive material you should use depends on the material you’re grinding or finishing: 

• For mild and softer steels, aluminum oxide is a good choice, as it is effective and highly affordable. Aluminum oxide sandpaper is also commonly used as an abrasive for sandpaper for sanding and finishing wood.
• For harder steels, ceramic or zirconia alumina is more practical as it allows for faster stock removal. 
• Aluminum-specific abrasives should be used with aluminum due to its unique mechanical properties. 
• For very hard materials, diamond, silicon carbide and some other carbides should be used, as these are harder and will last longer. They also allow for better precision and a better finished product. 

Grit Selection

What you are doing with the grinding abrasive in question should also affect grit selection. 

For instance, if you are:

• Doing heavy stock removal for shaping or profiling, 24-40 grit zirconia alumina or ceramic can be good options. These are long-lasting, hard, and can remove a lot of material quickly.
• For deburring, a slightly higher grit abrasive, in the area of 60-80 may be preferred. Flapwheels may also be effective for this as the wheel can follow the contours of the workpiece. 
• For finishing, you will want the highest grit practical, typically above 100 grit. For mirror polishing, grits above 1000 grit are necessary. 

Sandpaper, Wheels, Discs and More 

It is also important to consider the tool you’ll be using. For instance, grinding wheels are best used on a hard surface that’s flat or relatively flat, as they are not flexible. Flap wheels and wire wheels can follow the contours of a workpiece, enabling greater flexibility in producing a finish.

Other Things You Should Consider

In addition to what has already been covered here, you should also think about:

• The material of the workpiece; softer materials like wood will require different abrasives from metals like steel or aluminum.
• Surface finish requirements; heavy, low-grit abrasives will remove material quickly but will not generally leave a smooth finish.
• Application method; sandpaper is often used for manual sanding but bonded abrasives are often better with power tools and machinery. 

Explore Grinding Abrasives at TMT Toolbox

Whether you’re looking for a new supplier of sanding belts or just need to replace some grinding or cutoff wheels, visit TMT Toolbox. They carry a wide range of grinding abrasives, including all of those mentioned here in addition to many others. Visit their website for more information or get in touch with them today for assistance.

For more information about Machine Tool Accessories and Machinist Tools And Supplies Please visit: TMT Toolbox.