Blade Education Series — Part 3

Hollow:
The Measurement That Controls Your Edge

Every sharpening produces a hollow. Most players don't know what hollow they're on — or why it matters. Here's what's actually happening under your blade.

Advanced Blade Education
Hollow Spectrum Explained
How To Choose Your Hollow
In This Guide

03 // Hollow

What Is
Hollow?

Hollow is the concave groove ground into the bottom of your blade during sharpening. It's measured as the radius of the circle that would complete that arc — and it determines how deeply your edges bite into the ice.

Look at a blade from the front. The bottom isn't flat — it's a curved groove. The edges on either side of that groove are the two contact points that grip the ice. The deeper and narrower that groove, the more aggressive the bite. The shallower and wider, the more glide.

The hollow radius is expressed as a fraction of an inch. A 1/2" hollow means the groove was carved by a wheel with a 1/2-inch radius. Smaller fractions mean a deeper, sharper groove. Larger fractions mean a shallower, smoother groove.

Blade Cross-Section — Hollow Anatomy
ice surface depth Hollow Groove Left Edge Right Edge radius
Blade edges (contact points)
Hollow groove arc
Groove depth
The Key Relationship
Smaller number = deeper groove = more bite = less glide. A 3/8" hollow digs deep and grabs hard. A 1" hollow is nearly flat and lets you fly. Most competitive youth players fall somewhere between 1/2" and 5/8" — but they often don't know which, or why.

How Hollow
Works

Hollow controls the balance between grip and glide — the two fundamental forces that make skating possible. Every hollow is a trade-off between these opposing qualities.

When you push off or dig into a turn, your edges sink slightly into the ice. The deeper the hollow, the more they sink — and the more traction you generate. But deeper edges also create more drag. Your glide suffers, your crossovers feel heavier, and your top-end speed diminishes.

A shallower hollow gives your edges less bite but lets them skim more freely. Straight-line speed improves. Long stride efficiency goes up. But in tight turns, quick pivots, or hard stops, you may feel your feet sliding instead of locking in.

🔒
Edge Bite

Deeper hollows create sharper, more pronounced edges that dig into the ice — critical for explosive stops, tight turns, and quick direction changes.

💨
Glide Efficiency

Shallower hollows reduce drag during glide phases, improving straight-line speed and long-distance stride efficiency — key for wingers and defensemen.

↩️
Turning Power

More hollow depth means edges engage sooner and harder in a turn — you get higher edge engagement angles without slipping during crossovers and pivots.

🦵
Leg Fatigue

Hollow that's too deep for your body weight or skating style forces your legs to fight extra drag on every stride — which compounds over a full game.

"The right hollow isn't the deepest one. It's the one you understand and control."

The Hollow
Spectrum

Common hollows range from 3/8" (very aggressive) to 1" (very shallow). Each sits in a different spot on the grip-to-glide continuum, and each suits a different type of skater.

Hollow Spectrum — Grip vs. Glide
3/8" — Maximum Grip 1/2"–5/8" — Balanced 3/4"–1" — Maximum Glide
3/8"
Maximum bite. Very short radius = very deep groove.
Max Grip Low Glide
1/2"
Aggressive but manageable. Most common for youth/junior.
High Grip Moderate Glide
5/8"
Balanced. Good all-around for older competitive players.
Balanced Grip Good Glide
3/4"
Glide-oriented. Favored by heavier skaters and defenders.
Low Grip High Glide
1"
Near-flat. Maximum glide, minimal edge engagement.
Minimal Grip Max Glide
Reading the Numbers
The fraction refers to the radius of the grinding wheel's cup — not the depth itself. A 1/2" hollow uses a wheel with a half-inch radius, producing a deeper, narrower groove than a 3/4" hollow. The smaller the fraction, the deeper and more aggressive the cut.

What Nobody
Tells You

Most players know they get their skates sharpened. Almost none know that every sharpening resets their hollow — and that switching sharpeners is the same as switching hollows.

Every sharpening resets your hollow. The machine grinds away the previous groove and replaces it. If your sharpener uses a different wheel or a different setup, your hollow changes — even if the number on the form says the same thing.
Sharpening machines are not standardized. A "1/2" hollow" at one shop may feel different from a "1/2" hollow" at another. Wheel condition, dressing technique, and machine calibration all affect the result.
Most youth players have never had a consistent hollow. They get sharpened wherever is convenient — different shops, different tournaments, different machines. Their skates never feel the same two games in a row, and nobody connects the dots.
Your hollow preference changes as you develop. A 9-year-old on a 1/2" hollow is appropriate. The same player at 15, with more weight, strength, and skating skills, may skate better on a 5/8" or 3/4" — but no one has ever revisited it.
The Real Cost of Inconsistency
When your hollow changes unpredictably, your body compensates without you realizing it. You dig edges differently, adjust your weight, change your stride mechanics. Over time this builds bad habits — not because of your technique, but because your equipment keeps changing underneath you.

Does Your Hollow
Actually Fit Your Game?

Most players are on the wrong hollow for their size, position, or playing style. EDGE evaluates your current setup and recommends a hollow based on your actual skating — not guesswork.

Request a Blade Assessment Start from Part 1

Choosing
Your Hollow

There's no single correct hollow. The right one depends on your position, skating style, ice conditions, and body weight — and ideally, on feedback from someone who watches you skate.

Player Type Typical Hollow Why
Young / lighter skater (under 100 lbs) 3/8" – 1/2" Less body weight means less natural edge pressure — deeper hollow compensates to maintain grip.
Competitive youth, average build 1/2" – 5/8" Balanced grip and glide for the demands of competitive play. Most versatile range for developing players.
Forward — agility focus 1/2" – 5/8" Tighter turns, quicker starts, stronger edge engagement in offensive-zone plays.
Defenseman — power & stability 5/8" – 3/4" More glide for gap control and gap closing; sufficient grip for battle situations along the boards.
Goalie Varies widely Goalies often use asymmetric hollows or specialty profiles — hollow selection is highly individual.
Heavier skater (over 180 lbs) 5/8" – 3/4" More body weight naturally creates more edge pressure — a shallower hollow prevents over-digging and reduces fatigue.
Soft / poorly maintained ice 1/2" or shallower Soft ice already provides extra grip — a deeper hollow can cause edges to catch and trip on ruts and divots.
Hard / freshly cut ice 5/8" or deeper Hard ice reduces natural edge engagement — a deeper hollow restores grip on surfaces that would otherwise feel slippery.
The Starting Point Rule
If you don't know where to start: most competitive youth players (ages 10–14) do well on a 1/2" hollow. Older, heavier players (15+) often benefit from moving to 5/8". Go shallower if you feel like your feet are stuck. Go deeper if you feel like your feet are sliding. Make one change at a time, and give it at least 3–4 sessions.

Managing Hollow
Consistently

Knowing your hollow is step one. Making sure you get that hollow — every single sharpening, from the same machine — is what actually changes how your skates perform.

Most players can't feel a one-size change in hollow. But they can absolutely feel two or three sharpenings in a row from different places or different setups. The inconsistency compounds. By the time your body has adapted to one hollow, it changes again.

Professional players travel with their equipment manager for exactly this reason. Their skates are sharpened on one machine, by one person, to one spec, before every game. That consistency is part of their performance — not an afterthought.

Managed Hollow
Same hollow every session — body doesn't need to re-adapt
Hollow is adjusted intentionally as the player develops
Feedback from player gets captured and acted on
Sharpening history documented — you always know your spec
Unmanaged Hollow
Different result every sharpening — body constantly compensating
Same hollow used from age 8 to 16 without ever revisiting it
Issues blamed on skating technique when it's actually equipment
No record of what was done or what worked

Where This Fits
The EDGE System

Hollow doesn't exist in isolation. It works with your blade profile and your sharpening frequency to create a complete performance picture.

01
Hollow
Controls edge bite and glide — the foundation of every stride, stop, and turn. Part of every EDGE sharpening spec.
02
Profile
Controls how much blade contacts the ice and where your balance point is. Works with hollow to shape your overall skating feel.
03
Consistency
The multiplier. Knowing your hollow and profile only matters if you get them reliably — session after session, season after season.

If your skates feel different every time you step on the ice…

it might not be your legs. It might not be your technique.

It might be the groove under your blade — and no one ever told you.

Part 2: Blade Profile Get Your Blades Assessed →
Blade Education Series

Stop Guessing.
Start Managing.

EDGE brings structured blade management to competitive hockey players and programs. If you want your hollow tracked, your preferences documented, and your sharpening consistent — we should talk.