Choosing the right sharpening style and depth has always been a challenge. We like to offer you some insight into what the pro’s and con’s for each sharpening methods are and what they mean for a skater.


Radius of Hollow (ROH) is the conventional and "old" way of sharpening skates. It is the size in inches of the circular pattern applied to the bottom of the ice skate blades to provide two distinct edges. The ROH (r) is also referred to as a groove, a hollow grind or a ground radius.

The selection of a ROH has a direct effect on a skater's bite angle and therefore performance. A 1/2” or 5/8" ROH is considered standard. However, lower and higher ROH are also used. Higher ROH results in lower bite angles and conversely, lower ROH’s result in higher bite angles.
The Flat Bottom V is a new way of sharpening skates. This innovation from Blackstone Sports provides more advantages in comparison to the ROH.

FBV Pro's
• Better gliding and turning abilities
• Smoother and more dynamic actions
• Less fatigue
• Excellent performance in combination with contouring
• Runners last longer (less material removed per sharpening)
• Faster skating than with ROH sharpening (less drag)
• Ideal for young players (easier to stop, better use of edges)
The BFD sharpening, or also called FBC (Flat Bottom Circular Arc), follows the same Flat Bottom idea. However, it is not identical to the Flat Bottom V since it uses curved (r) edges. This edge creates a significant disadvantage as small tolerances in blade thickness and/or sharpening offsets will create bite variances.

Some shops offer FBV but deliver actually an FBC/BFD sharpening. This sharpening type is not available at Edgehogs. Therefore try the real FBV from Blackstone.

T = Thickness of Blade
r = Radius
D = Depth
W = Width
α = Bite Angle