Grinding Wheels Dressers | CRATEX Abrasives

Grinding wheel dressers can be broadly divided in following categories:

• Dressing rolls and rotary tools – these dressers have rolls or wheels that are coated with diamonds;
• Dressing spindles - spindle-mounted tools that usually come with an integral brake and drive;
• Dressing sticks – or dressing blocks are made of bonded abrasives;
• Impregnated or grit dressing tools – these have a whole layer of diamond or superabrasive grains bonded in the matrix, much more sharp points than an ordinary multi-point tool. These are used in the same way as multi-points tools, but they are designed to provide a superior finish;
• Single-point dressing tools – these have only one diamond or superabrasive grit bonded in the tip and can be various: single point tools should be mounted at a 10°-15° angle to the wheel centerline while the contact point should be slightly below the centerline. The tools should point in the direction of wheel travel;
• Multi-point or Cluster dressing tools – unlike the single-point ones, cluster dressers have several diamonds or superabrasives across the dresser surface. They can be wide enough to reach across the entire cutting surface of the grinding wheel and most of them are used for straight-face dressing. They came into use mostly because they’re more affordable (instead of one large diamond they have several smaller ones).

 

Grinding wheel dressers used most often on bench grinders are as follows:

 

• Dressing sticks

These are dressing bonded abrasives shaped as a stick or a block. You’ll usually use dressing blocks made from the same abrasive type as the grinding wheel, but you’ll choose a stronger bonding agent. Typical abrasives used in grinding wheel dressing sticks are aluminum oxide and silicon carbide. For resin and vitrified bond diamond and cBN wheels you should choose a dressing stick that is one or two grit sizes finer than the abrasive in the wheel. For metal bond diamond choose a stick the same grit size or one grit size coarser than the wheel abrasive.

• Star or disc dressers

These are heavy-duty dressers with long handles, a row of hardened free running either star-shaped cutters or wavy discs, and little ‘legs’ that are designed to go behind the tool rest. Star dressers provide a more ‘open’ texture, which is perfect for rough grinding, and they are more suitable for larger (e.g. 12″) grinders. They are consumable items that are going to wear down, so you’ll need to change the discs after they do.

• Diamond Dressers

These dressers have a short handle and you can find two types. Either those with a single diamond embedded in their face, or those with a lot of small diamonds embedded in a wide surface. Diamond is the hardest superabrasive used for truing and dressing conventional and superabrasive grinding wheels. It’s ideal for fine finishing cutting tools as it gives the grinding wheel a smoother finish. Although diamond dressers might seem pricey initially, rest assured you’ll get your money’s worth, since diamond is extremely durable and therefore a long-lasting tool.

When it comes to CNC grinders, four types of dressers can be used for dressing their wheels.

• Crush rolls

This is a wheel made of either high-speed steel or tungsten carbide, which is pressed against the grinding wheel while spinning at the same speed as the wheel. The dresser profile is the mirror image of the desired grinding wheel profile and cannot be adjusted, only replaced by a different profile.

• Diamond crush rolls

This would be a crush roll which is coated with diamond grains. Diamond grains give them an advantage over regular crush rolls, because they wear more slowly.

• Stationary dressers

These have a metal blade that has a single diamond embedded in the tip. A CNC program for dressing the wheel controls the wheel’s profile and is responsible for moving the dresser across the wheel’s surface.

• Rotary dressers

These are sometimes called ‘pizza cutters’. A disc made of material (usually a diamond) is attached to the edge, and the grinding wheel’s profile is controlled by the CNC program used to wheel dressing as well.