Skate sharpening explained: radius of hollow, profiling and how often

Weight comes first, because it presses the blade into the ice. A light player needs a deeper hollow to get the same grip; a heavy player bites enough with a flatter one. That is the principle CCM gives, without a number; the ranges below come from sharpening shops and retailers.

The bottom of a blade is not flat: the grinding wheel cuts a groove that leaves two edges, one inside and one outside. The hollow number (the radius of hollow, or ROH) is the radius of the circle that cut the groove. A small radius cuts a deep groove with tall, sharp edges. A large radius cuts a flat groove with lower edges.

Hence the rule to remember: the smaller the number, the more the skate bites. A 1/2 in (12.7 mm) hollow grips better in turns and stops but slows the glide slightly. A 5/8 in (15.9 mm) hollow glides farther on every push, with a bit less grip. In hockey, most players sit between 3/8 and 5/8 in.

Change one step at a time, and give yourself two or three skates before judging: the first session on a new hollow always feels a little strange.

People often mix them up at the counter. The hollow shows in cross-section: the groove under the blade, measured in inches. The profile shows from the side: the curve of the blade from front to back, measured in feet, which decides how much steel touches the ice. Profiling is a separate job, done on a machine that gives the blade a precise shape.

CCM gives a simple rule: for kids and beginners, a standard single-radius profile; for experienced players, a custom profile; for elite players, combined radii based on position and style. A U9 kid does not need a Quad. They need blades that are sharpened often.

Guidelines contradict each other when counted in weeks, because a hockey week means nothing on its own: one player skates an hour, another six. Count in hours of ice time instead. Here is what the sources say, from strongest to weakest.

The simplest method: write down the date of your last sharpening, then add up the sessions since. If you keep your games and practices in RinkLog, the calendar already holds them; it won't send you a sharpening reminder, but the count takes a glance. The ice time guide explains how to estimate what one game represents.

The skate tells you before the calendar does. These signs come up with every sharpener:

In a child, these signs often pass for fatigue or a lack of skill. A kid falling more than usual in turns deserves a look at their blades before a lecture. That is also why CCM aims for a weekly sharpening for young players: they can't yet tell when a blade is worn.

A goalie doesn't skate like a player: they push sideways and slide on their edges to track the puck. A hollow that is too deep grabs during those slides. So goalies get a shallower hollow than skaters, often around 1 in or more according to one specialty retailer.

That is a single source, and preferences vary a lot from goalie to goalie. Start there, then adjust with your sharpener by feel: if lateral pushes lack grip, go a little deeper; if the skate grabs in slides, go flatter. The rest of a goalie's gear has its own rules, covered in goalie equipment sizing.

Steel gets replaced several times over the life of a skate, since every sharpening removes a little metal. You still need the right one: the steel must be made for your skate's holder, not just its brand.

New steel often arrives unsharpened, or with a basic sharpening: ask for your usual hollow before you skate again. To see whether premium steel is worth the price for your use, read is it worth investing in hockey gear.

It is one of the few studies on the topic. In a master's thesis submitted at Brock University (Ontario) in 2016, L. Cadeau had 40 hockey players (21 U16, 10 U18 and 9 Minor Midget AAA) skate 8 timed drills on two different sharpenings.

The result: the “recommended” sharpening produced faster times on 4 of 8 start measures and on 2 of 8 total times, with statistical significance (p < 0.05). On the other measures, the gap was not significant.

Two limits to keep in mind. First, the recommended sharpening combined three settings, profile, hollow and pitch (whether the curve leans forward or back): the study cannot say which one made the difference, and hollow alone was not isolated. Second, it is a thesis on 40 young players, not a universal rule. What you can honestly take from it: a well-matched sharpening can improve starts, and it is worth thinking about before a tryout camp.

For full camp preparation, see preparing for hockey tryouts.

Ask for your hollow by its number (“1/2”, “5/8”) rather than “the usual”: a new shop does not know your usual. Three habits are enough to get the same result every time.

And if you are buying new skates, size comes before everything else: a perfect sharpening cannot save a poorly fitted skate. The hockey skate size chart gives the size and fit by model.