Help Breaking Snowplow Cutting Edge

[MikePhua]

Introduction
Snow removal has long been a vital task in regions where winter storms can shut down entire communities. Among the essential tools in this work is the snowplow cutting edge, the replaceable strip of hardened steel or composite material that makes direct contact with pavement. While it seems like a simple component, many operators encounter problems when trying to break or replace a cutting edge after extended use. Understanding why this task is difficult requires looking into the engineering behind plow blades, the stresses involved in winter operations, and the methods commonly used to deal with worn parts.
The Role of the Cutting Edge
A snowplow cutting edge serves as the working face of the plow. It clears compacted snow, scrapes ice, and withstands constant abrasion against asphalt and concrete. Cutting edges are usually made of heat-treated carbon steel, hardened to around 250–400 Brinell Hardness Number (BHN). Some municipalities have shifted to carbide-insert edges, which last up to four times longer than plain steel but are notoriously difficult to cut or drill once worn down.
The difficulty in breaking or cutting an edge lies in this very design. They are intentionally manufactured to resist wear and deformation, meaning standard shop tools often fail against them.
Why Cutting Edges Are Hard to Break

1. High Hardness – With steel tempered for durability, most edges resist saw blades and grinders. This ensures long service life but complicates replacement.
   
2. Edge Thickness – A cutting edge may measure 5/8 inch to 1 inch thick, depending on the plow type. This mass of hardened steel requires heavy-duty methods for separation.
   
3. Bolt Corrosion – Often, the cutting edge is not just hard to cut, but also hard to remove due to rusted mounting bolts, especially after repeated exposure to road salt.
   
4. Continuous Impact Stress – Over time, plow edges mushroom or crack. When operators attempt to break them for disposal or resizing, these stress points may cause unpredictable fractures.
   

Common Techniques for Breaking or Cutting
Operators and mechanics have developed several methods to deal with stubborn plow edges:

• Oxy-acetylene torch – A traditional method where heat cuts through hardened steel quickly. The drawback is risk of heat distortion and fire hazards in a shop setting.
  
• Plasma cutter – A faster, cleaner option capable of slicing through even carbide-insert edges. However, it requires specialized equipment and power.
  
• Hydraulic press or shear – Large maintenance shops sometimes use industrial presses to snap cutting edges along pre-drilled holes. This is efficient but impractical for smaller garages.
  
• Angle grinder with abrasive discs – While slow, this method works if carbide inserts are absent. Frequent disc replacement is necessary.
  
• Mechanical drilling and chiseling – In rare cases, drilled holes combined with chisels or wedges allow a section to be broken free. This is labor-intensive and only suited for field repairs.
  

Safety Considerations
Attempting to break a cutting edge carries risks. Hardened steel, when fractured under pressure, can send shards flying with extreme force. Operators are strongly advised to wear full face shields, protective gloves, and heavy clothing. Fire risks from torches and plasma cutters must also be mitigated with extinguishers and controlled environments.
Lessons from the Field
One county highway department in Minnesota reported that when they transitioned from standard steel to carbide edges in the late 1990s, their replacement cycle extended from roughly 200 hours of plowing to nearly 800 hours. However, they also discovered that disposal and resizing became much more difficult, leading to investments in plasma cutters for their fleet shops.
Another example comes from a private snow removal contractor in New England, who found that attempting to cut worn blades with standard tools wasted both time and money. They ultimately switched to ordering pre-sized replacement edges from the manufacturer, which streamlined operations despite higher upfront costs.
Evolution of Snowplow Cutting Edges
The snowplow blade itself dates back to the early 20th century, when cities first mounted plows onto trucks to replace horse-drawn scrapers. Early edges were simple mild steel strips bolted onto moldboards. By the 1950s, hardened steel edges became standard, and by the 1980s, carbide-insert technology emerged. Today, manufacturers such as Fisher, Western, and Boss sell thousands of units annually across North America, where an estimated 150 million people live in regions with regular snowfall.
Municipal contracts often include bulk orders for cutting edges, with large cities using several thousand per winter season. This high demand has pushed suppliers to balance durability with serviceability, though breaking and cutting hardened edges remains a persistent challenge.
Practical Recommendations

• Use specialized cutting equipment such as plasma cutters if available.
  
• When possible, replace rather than modify worn edges to save labor time.
  
• Apply anti-seize compounds to mounting bolts during installation to ease removal later.
  
• Store spare edges indoors to reduce rust buildup.
  
• For contractors managing fleets, consider standardizing blade types to simplify maintenance.
  

Conclusion
Breaking a snowplow cutting edge is no easy task, and it was never intended to be. These components are designed for maximum wear resistance and durability in harsh winter conditions. While older mild steel edges could be cut with basic tools, modern hardened and carbide-insert designs demand more advanced equipment and safety precautions. For operators, the most efficient path often lies not in forcing a break but in using the right tools or opting for pre-sized replacements. In the end, the cutting edge remains a perfect example of how equipment durability can sometimes complicate maintenance, forcing a balance between resilience and repairability.