The hollow on ice skate blades is the concave groove ground into the bottom of your blade during sharpening. This groove creates two sharp edges on either side of the blade that bite into the ice, giving you the grip you need to turn, stop, and accelerate. Without the hollow, your skate blades would be flat metal strips that slide uncontrollably across the ice surface.
Understanding blade hollow changed how I approached skating. For years I walked into pro shops and simply asked for a “standard sharpen” without knowing what that meant. Once I learned how hollow affects performance, I could communicate exactly what I needed and finally got consistent results from every sharpening.
In this guide, I will explain everything about the hollow on ice skate blades. You will learn how it is created, why the radius concept confuses so many skaters, and how to choose the right hollow for your weight, position, and skating style. Whether you play hockey, figure skate, or just enjoy recreational skating, this knowledge will help you get more enjoyment and better performance from every session on the ice.
Table of Contents
What Is the Hollow on Ice Skate Blades?
The hollow is a concave groove running lengthwise along the bottom of your skate blade. Imagine cutting a U-shaped channel down the center of a metal bar. That channel is your hollow. It is created during the sharpening process when a grinding wheel cuts into the blade surface.
This groove creates two distinct working edges on your blade. The inside edge on the left side of each blade and the outside edge on the right side give you the ability to grip the ice. When you lean into a turn, these edges cut into the ice surface and provide the lateral force that changes your direction.
Picture a blade cross-section viewed from the front. Without a hollow, the bottom would be flat like a rectangle. With a hollow, the bottom curves upward in the center, forming a shape like the letter “U” lying on its side. The two high points at the edges are what actually contact the ice. The depth of that center curve determines how aggressively your skates bite into the ice.
The technical term for this measurement is “radius of hollow,” abbreviated as RoH. It refers to the radius of the imaginary circle that matches the curve ground into your blade. A smaller radius number means a tighter curve and a deeper hollow. A larger radius means a flatter curve and a shallower hollow.
How Is the Hollow Created During Sharpening?
The hollow is created when your skate blade passes across a rotating grinding wheel. The wheel has a curved profile that matches the radius of hollow you want. As the blade moves along the wheel, that curved surface cuts a matching arc into the bottom of the blade.
Think of it like pressing a cookie cutter into dough. The grinding wheel acts as the cutter, and its curved edge imprints that shape onto your blade. The operator selects a grinding wheel with the appropriate radius for your desired hollow. Common wheel profiles include 3/8 inch, 1/2 inch, 5/8 inch, and 3/4 inch radii.
During sharpening, the blade is clamped in a holder that keeps it steady. The operator guides it across the spinning wheel with light, even pressure. Each pass removes a tiny amount of metal and deepens the hollow slightly. Most sharpenings take multiple passes to achieve the proper depth and ensure both edges are even and sharp.
The sharpening machine also dresses the sides of the blade, creating the actual cutting edges. The hollow determines how much of those edges bite into the ice. A deeper hollow means the edges sit lower relative to the center of the blade, creating more aggressive bite.
Understanding Radius of Hollow: The Counter-Intuitive Concept
The most confusing aspect of blade hollow is the relationship between radius size and hollow depth. It feels backward. A smaller radius number actually creates a deeper hollow, while a larger radius creates a shallower hollow.
Here is why this happens. Imagine drawing circles of different sizes. A small circle has a tight curve. A large circle has a gentle, gradual curve. The grinding wheel works the same way. A 3/8 inch radius wheel is a small circle with a sharp curve. When it cuts into your blade, it creates a deep U-shaped groove.
Now picture a 3/4 inch radius wheel. This is a much larger circle with a gentler arc. When this wheel cuts your blade, it creates a shallow, wide groove. The blade bottom is nearly flat with just a slight curve in the center. Many beginners ask for a “bigger hollow” thinking they want more bite, but a bigger radius number actually means less bite.
I remember my own confusion when a shop tech told me 3/8 was “sharper” than 5/8. I thought 5/8 was a larger number so it should be sharper. It took a visual diagram to finally make it click. The 3/8 circle is smaller and curves more aggressively, creating that deeper hollow and sharper bite.
Deep Hollow vs Shallow Hollow: Effects on Skating Performance
The depth of your hollow fundamentally changes how your skates feel on the ice. Understanding these differences helps you make an informed choice about what works best for your skating style.
A deep hollow uses a smaller radius like 3/8 or 7/16 inch. The blade edges sit well below the center of the blade. When you step onto the ice, those edges bite aggressively and dig in. You get tremendous grip for tight turns and quick stops. Acceleration feels explosive because your pushes grab the ice immediately.
But deep hollows come with trade-offs. All that bite creates friction. You do not glide as far between pushes. Your top speed suffers because the blades are constantly fighting against the ice surface. Some skaters describe the feeling as “sticky” or “grabbing.” You might also feel your blades “chattering” or vibrating during hard stops.
A shallow hollow uses a larger radius like 5/8 or 3/4 inch. The blade bottom is flatter with edges that sit closer to the center level. These edges still bite into the ice, but less aggressively. You get a smoother, freer feeling glide. Your strides carry you further with less effort.
The trade-off with shallow hollows is reduced bite. You may feel your feet slip slightly when trying hard lateral cuts. Stopping power decreases, especially for quick hockey stops. Some skaters describe the feeling as “blowing a tire” when the blade loses grip during a sharp turn.
The Grip vs Glide Trade-Off
Every skater faces the same fundamental decision: how much grip versus how much glide do you want? There is no universal right answer. The perfect hollow depends on your priorities and skating style.
Players who value agility and quick changes of direction usually prefer deeper hollows. Defensemen who need to stop on a dime and accelerate quickly often like 1/2 or 7/16 inch hollows. Figure skaters doing jumps and spins need reliable edge grip and often choose deeper hollows for control.
Players who prioritize speed and efficiency typically prefer shallower hollows. Forwards who skate long shifts and want to maintain top speed often choose 5/8 or 3/4 inch hollows. Recreational skaters who just want a smooth, easy glide around the rink often prefer shallower hollows too.
The grip-glide spectrum is continuous, not binary. You can find your personal sweet spot anywhere along the range from 3/8 inch (maximum grip) to 1 inch or more (maximum glide). Most hockey players settle somewhere in the 1/2 to 5/8 inch range. Figure skaters often go slightly deeper for better edge control.
How to Choose the Right Hollow for Your Skates
Selecting the right hollow involves balancing several factors. Here are the five key considerations that should guide your decision.
Factor 1: Your Body Weight
Heavier skaters need more shallow hollows. Your weight drives the blade deeper into the ice naturally. A 200-pound player on a 3/8 inch hollow would sink in so aggressively that skating would feel like wading through mud. Most heavy players prefer 5/8 or 3/4 inch hollows to compensate.
Lighter skaters need deeper hollows to get adequate bite. A 120-pound youth player on a 3/4 inch hollow might find the blades slide out during turns because there is not enough weight to make the edges bite. Youth and lightweight players often do better with 1/2 or 7/16 inch hollows.
My experience as a 175-pound player confirms this pattern. I started with a standard 1/2 inch hollow and always felt a bit sluggish. When I switched to 5/8 inch, my skating immediately felt freer and faster. The shallower hollow suited my weight better.
Factor 2: Your Position
Hockey forwards typically skate longer shifts and need sustained speed. They often prefer 5/8 or even 3/4 inch hollows for the glide efficiency. The trade-off in bite is acceptable because they are not making as many sharp defensive stops.
Defensemen need explosive acceleration and the ability to stop quickly when covering opponents. They often prefer 1/2 or 7/16 inch hollows for the extra bite. The reduced glide matters less because their shifts are often shorter and more intense.
Goalies have unique needs. They need to slide side to side smoothly but also need grip for post movements. Traditional goalie hollows were 3/4 to 1 inch for maximum glide. Modern butterfly-style goalies often use 1/2 or 5/8 inch for better grip during pushes and recoveries.
Factor 3: Ice Conditions
The hardness of your rink ice significantly affects how your hollow feels. Hard ice is dense and requires more bite to get grip. On hard ice, a hollow that feels perfect on normal ice might feel slippery. Many players go one step deeper for hard ice conditions.
Soft ice is less dense and offers more natural grip. Your blades sink in more easily. On soft ice, your normal hollow might feel too grabby and slow. Players often go one step shallower for soft ice.
Outdoor rinks in cold winter conditions usually have hard ice. Indoor rinks in warm, humid weather sometimes have softer ice. Talk to regulars at your specific rink about the typical conditions and adjust accordingly.
Factor 4: Your Skill Level
Beginners often benefit from slightly shallower hollows. The reduced bite makes skating feel more forgiving. You are less likely to catch an edge and trip. The smoother glide helps you build confidence and enjoy the experience.
Advanced skaters have the ankle strength and technique to control aggressive edges. They can take advantage of deeper hollows for maximum performance. Elite skaters know exactly what they want and often have very specific preferences.
Forum discussions reveal that many adult beginner hockey players struggle with factory-sharpened 1/2 inch hollows. Switching to 5/8 inch makes the game more enjoyable while they develop their skating legs.
Factor 5: Personal Preference
Ultimately, hollow selection is personal. Some players simply like the feeling of blades biting hard into the ice. Others prefer the smooth freedom of a shallow hollow. Both can be successful with proper technique.
The best approach is to start with a reasonable middle ground like 1/2 or 5/8 inch. Skate on it for several sessions. Then try one step deeper or shallower and compare how it feels. Keep experimenting until you find what works for you.
Figure Skating Hollow vs Hockey Skate Hollow
Figure skaters and hockey players have different hollow needs based on their distinct skating styles. Understanding these differences helps if you participate in both sports or are helping a young skater choose their setup.
Figure skaters typically use deeper hollows than hockey players. The need for precise edge control during spins, jumps, and footwork sequences demands reliable bite. Most figure skaters use hollows between 3/8 and 1/2 inch. Dance and synchro skaters sometimes go slightly shallower for the gliding elements.
The blades themselves are different too. Figure skate blades are longer, flatter, and have toe picks at the front. They are designed for different mechanics than the curved, shorter hockey blades. The sharpening process accounts for these blade differences.
Hockey players need a balance between grip for quick maneuvers and glide for speed during long shifts. Most adult hockey players settle between 1/2 and 5/8 inch. Youth hockey players might start at 1/2 inch and adjust as they grow and develop preferences.
If you participate in both sports, you will likely want different hollows for each pair of skates. Many skaters find that a deeper hollow on figure skates and a shallower hollow on hockey skates works best.
Traditional Hollow vs Flat Bottom Hollow
Most skaters are familiar with the traditional U-shaped hollow. However, a newer sharpening style called flat bottom hollow (FBV) has gained popularity in recent years. Understanding the difference gives you more options for optimizing your setup.
The traditional hollow uses a continuous curved profile across the blade bottom. The cross-section looks like a smooth “U” shape. This design has been standard for decades and works well for most skaters.
Flat bottom hollow uses a different grinding wheel profile. The center of the blade remains relatively flat with just a small hollow channel. The edges are sharp and high like traditional sharpening, but the blade glides on a flatter surface between the edges.
Proponents of FBV claim it offers the best of both worlds. You get the edge bite for turning and stopping, but the flatter center provides more glide. Many players report feeling faster with FBV while maintaining adequate control.
Traditional hollow remains more widely available. Not all pro shops have FBV equipment. If you travel frequently or need emergency sharpenings on the road, traditional hollow is more practical. If you have a local shop that offers FBV and you want to experiment, it might be worth trying.
What Hollow Comes on New Skates From the Factory?
New skates straight from the manufacturer often arrive with a factory sharpening already applied. Understanding what you are getting helps you decide if you need to change it.
Most hockey skates ship with either a 1/2 inch or 3/8 inch hollow from the factory. The exact specification varies by manufacturer and sometimes by model. Entry-level skates often come with 1/2 inch. Performance models sometimes ship with 3/8 inch for that aggressive bite.
Many skaters, especially beginners, find factory hollows too deep. The 3/8 inch hollow that feels great to a pro might feel grabby and unstable to a new skater. If you are buying your first pair of skates, plan to get them sharpened with a more moderate hollow before your first serious skating session.
Figure skates usually ship with basic sharpening that may not be optimized for your needs. New figure skates often need professional sharpening to ensure the edges are even and the hollow matches your skating style.
The sharpening on new skates may also be uneven or inconsistent from sitting in boxes. Even if the hollow depth is right, a fresh sharpening ensures both edges are level and properly shaped. I recommend getting new skates sharpened before using them seriously.
Frequently Asked Questions
What skate blade hollow do NHL players use?
NHL players use a wide variety of hollows based on personal preference. Most fall between 1/2 inch and 5/8 inch. Some forwards prefer shallower hollows around 3/4 inch for speed. Some defensemen go deeper to 7/16 inch for maximum grip. There is no standard NHL hollow – elite players experiment until they find what works for their specific needs and style.
What hollow should I get?
Start with 1/2 inch if you are a beginner or intermediate skater. This middle-ground hollow gives you enough bite to control your edges while providing decent glide. After skating on it for a few sessions, adjust deeper if you want more grip or shallower if you want more speed. Your weight matters too – heavier skaters should start with 5/8 inch while lighter skaters might prefer 7/16 inch.
What hollow do most figure skaters use?
Most figure skaters use hollows between 3/8 inch and 1/2 inch. Singles skaters doing jumps and spins often prefer 3/8 or 7/16 inch for the control. Ice dancers sometimes use slightly shallower hollows around 1/2 inch for the glide requirements of dance patterns. The hollow depends on the skater’s weight, skill level, and specific discipline within figure skating.
How do I know if my hollow is wrong?
Signs that your hollow might be wrong include feeling unstable during turns, sliding out when you try to stop, or feeling like your skates are sticking to the ice. If you feel like you are working too hard to maintain speed, your hollow might be too deep. If you cannot trust your edges in tight turns, your hollow might be too shallow. Experimenting with small adjustments helps you find the right balance.
What is the best hollow for beginners?
Most beginners do well starting with a 1/2 inch hollow. This provides enough bite to learn edge control without being so aggressive that you catch edges and trip. Youth beginners might even start at 5/8 inch for a more forgiving feel. As you develop ankle strength and technique, you can experiment with deeper hollows if you want more performance.
How often should I get my skates sharpened?
Most regular skaters should get their skates sharpened every 10 to 15 hours of ice time. If you skate daily, that might mean weekly sharpening. If you skate once a week, you might go a month between sharpenings. Signs you need sharpening include nicks or burrs on the edges, difficulty holding edges during turns, or a general feeling of slipping on the ice.
Conclusion
Understanding what is the hollow on ice skate blades helps you make informed decisions about your equipment. The hollow is that concave groove ground into your blade bottom during sharpening. It creates the two edges that bite into the ice and give you control.
The relationship between radius size and hollow depth confuses many skaters at first. Remember that smaller radius numbers like 3/8 inch create deeper hollows with more bite. Larger radius numbers like 5/8 or 3/4 inch create shallower hollows with more glide.
Choosing the right hollow involves balancing your weight, position, ice conditions, and personal preference. Start with a moderate 1/2 inch hollow and experiment from there. Pay attention to how your skates feel during different maneuvers. Adjust gradually until you find the sweet spot that gives you confidence on the ice.
The best skaters I know are particular about their hollows. They know exactly what they want and can communicate it clearly to their sharpening technician. Take the time to understand your own preferences. Your skating will improve when your equipment is tuned to your specific needs.