SHARPENING TIPS

What Radius of Hollow (ROH) Is Right for Me?

The selection of a Radius of Hollow for your skate blades is an individual decision, but we can give you the facts and recommendations to help make your decision easier.

The Radius of Hollow determines the bite angle of each blade edge. The selection of ROH and bite angle determines the performance characteristics of the blade. The correct application of any ROH results in a blade with sharp edges. A smaller radius of hollow 1/4" ROH means that a blade will have edges with higher bite angles than a blade with a larger radius of hollow 1" ROH. The higher bite angles result in edges which penetrate the ice deeper increasing drag and requiring more energy to accelerate.

What ROH do the NHL payers choose?

The most common choice of radius of hollow for hockey players is 1/2". According to a recent study of all NHL players 47% choose to skate on a 1/2" ROH. The next most common ROH in the NHL is 5/8" ROH.

Begginers and recreational skaters should try an ROH of 5/8" or 3/4".
Better Glide - Skaters select higher ROH's (1" or higher) when they are looking for increased glide.
More Friction - Skaters choose lower ROH's (3/8" or lower) when they are looking for more friction and control.

Inconsistent ROH (Radius of Hollow)

Due to a combination of sharpening equipment tolerance variations, lack of operator training, and poorly marked settings, ROH can vary from machine to machine, operator to operator, and shop to shop. Even though a skate can be perfectly sharpened, changes in ROH will give a different feel due to change in bite angle. This may give the impression of an improper sharpening.

Proper Skate Sharpening

For proper sharpening, the radius of hollow must be centered down the middle of a skate blade. This results in an equal bite angle on both inside and outside edges.

An off-center sharpening will result in one edge being higher than the other and different bite angles from edge to edge. Most sharpening machines require the operator to center the grinding wheel on the skate blade by eye. Therefore, the training, judgement, and conscientiousness of the operator can greatly affect the quality of the sharpening.

Poorly Dressed or Worn Grinding Wheels

The radius of hollow must be applied to the grinding wheel with a diamond stylus. Poor operation techniques and/or out of tolerance stylus can result in miss-sized or out of shape profiles being applied to the grinding wheels. Frequent wheel dressing is required to maintain the proper shape. With use, the grinding wheel profile will wear and change. This can result in incorrect or uneven bite angles.