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National 8274-4 Planetary Floor Preparation System

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National 8274-4 Planetary Floor Preparation System

Regular Price: $14,752.00

Special Price $10,601.00

Finance this product for as little as $241.70 per month! Click here to learn more.

The National 8274-4 is the only grinder on  the market offering 3 HP in a 115-volt grinder that operates at a 230-volt level.



With enough power to handle large and small jobs, the 8274-4 is the only grinder on  the market offering 3 HP in a 115-volt grinder that operates at a 230-volt level. Easy to operate control box offers variable speed to help control the amperage draw of the grinder. No more tripping circuit breakers!!


  • The 8274-4 has a 230 volt 3 HP motor that promotes a unique, National engineered, LED control box allowing the grinder to operate using 115 volt power. 
  • This active planetary grinder uses National’s patented self-tensioning, single belt technology to efficiently prepare concrete surfaces for coating applications and polishes to a 3000 grit shine. 
  • At almost 400 pounds, the 8274-4 provides down pressure, power and precision for jobs of all sizes.
  • The self-diagnosing control box has a variable speed feature that minimizes tripped circuit breakers.
  • The forward and reverse function increases tooling productivity through cleaner consumables and more even wear.
  • The easy flip style side weight system applies additional down pressure when required.
  • The grinder head rotates 90 degrees granting easy access to the quick change magnetic tooling. This provides safe and convenient change-out for multiple applications.
  • The floating 9292 isolator assemblies enable the magnetic tooling to follow the contour of the concrete surface. This provides a uniform scratch pattern for coating applications or polishing concrete with surface undulations.
  • The adjustable rubber dust guard provides a nearly dustless operation.
  • Designed to be used in conjunction with National's 3474-L HEPA dust collector.
  • The handle adjusts to a comfortable angle, height and grip.
  • The modular design grants quick and safe transportation.
  • This grinder promotes ease and maneuverability in small spaces and detailed edging within 1/8” to the wall.
  • This machine operates a complete dry grind and polish system; eliminating messy and hazardous slurry. 
  • There is a one (1) year manufacturer’s warranty on parts and labor.

Included with 8274-4

  • 9241: Quick Change Tool Holder Assembly (3)
  • 9245: Velcro Plate Adapter (3)
  • 9292: Floating Isolator (3)
  • 8274-45: Rubber Dust Guard
  • 6280-401B: 7/32 T-handle Allen Wrench
  • 6254: 50 foot 12 gauge Extension Cord
  • 1009: Safety Glasses
  • Instruction Manual

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Additional Information

Additional Information

Manufacturer National
Product Type Surface Preparation
SKU N-8274-4