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American Quality | Freight Delivered Nationwide | U.S. Based Support
American Quality | Freight Delivered Nationwide | U.S. Based Support

8274-4 Planetary Grinder | National Flooring Equipment

Original price $13,982.60 - Original price $13,982.60
Original price
$13,982.60
$13,982.60 - $13,982.60
Current price $13,982.60
Authorized Dealer Sourcing
Financing Available for Eligible Orders
Contractor-Grade Equipment

Shipping: LTL freight. Commercial delivery preferred.

The 8274-4 is an 18.5 in planetary grinder that preps and polishes concrete to a 3000-level polish on a 3 HP motor. A built-in soft start controls amperage draw and an upgraded box lets a 115 V machine work at a level normally needing 230 V, with amps switchable between 15 and 20.

Need fitment or freight help before you order? Contact our team.

Shipping & Freight

For an order containing products from a single brand, shipping is a flat rate based on your order total:

  • Orders up to $5,000: $279
  • Orders $5,000 to $10,000: $347
  • Orders $10,000 and over: $517

These rates cover standard freight delivery to a commercial address. After you place your order, our team will confirm your delivery timeline within 1 to 3 business days.

Ordering from more than one brand? Multi-brand orders ship on separate freight and are quoted individually rather than at the flat rate above. Place your order or contact us first and we will confirm total freight before anything is finalized.

Liftgate service is not included in these rates. If your delivery location has no loading dock or forklift to unload the freight from the truck, liftgate service is required and will be added to your shipping charge. If you are unsure whether you need it, contact us before ordering.

Commercial delivery locations are preferred when available. Residential delivery, limited-access locations, and appointment scheduling may affect handling.

Lead times vary by product, manufacturer availability, and selected options. Some configured, special-order, or non-stock items require additional processing time before they ship.

Please inspect all freight shipments at delivery before signing. If you see visible damage, note it with the carrier and contact us as soon as possible.

If you need freight, delivery, or lead-time guidance before ordering, contact our team before you purchase.

Compatibility / Fitment

Compatibility varies by product type, machine setup, selected options, and intended application.

For machine-mounted equipment and attachments, buyers should confirm fitment before ordering using the relevant machine information, including model, attachment style, mount type, coupler type, hydraulic requirements, and any other product-specific requirements listed on the page.

Hardscape Heavy can assist with pre-order fitment guidance based on the information you provide. This guidance is limited to purchase and compatibility review before ordering and does not include field installation, hydraulic modification, fabrication, or on-site setup support.

If you are unsure whether a product will work with your machine or application, contact us before placing the order.

Specifications

Core Specs

  • Disk Size: 18.5 in (47 cm)
  • Motor: 3 HP (2.24 kW)
  • Motor Speed: 400 to 2,000 RPM
  • Weight: 388 lb (176 kg)
  • Voltage: 115 V
  • Width: 20 in (51 cm)


Need full technical detail?
See the Technical Details tab. If available, also see manufacturer PDF in the Downloads tab.

Returns & Warranty

Warranty coverage is provided by the product manufacturer where applicable. Warranty terms, coverage periods, exclusions, and claim procedures vary by brand and product type.

Hardscape Heavy does not create separate warranty coverage beyond the manufacturer’s warranty unless explicitly stated on the product page.

Returns are governed by our store return policy. Because many products in this category involve freight shipping, special ordering, or configuration-specific selections, return eligibility may vary by product and condition. Special-order, custom-configured, used, damaged, or installed items may not be eligible for return.

Please review our full return policy before purchase. If you have questions about return eligibility or manufacturer warranty coverage for a specific item, contact us before ordering.

The 8274-4 is the grinder for a contractor who wants a large machine's output without a large machine's supply. It runs on ordinary building power and, in the supplier's own description, works at a level normally associated with a 230 V machine, which is what puts a high polish inside reach of buildings that have no three-phase drop.

The soft start is the component that makes that possible. Starting a heavy grinding head draws current sharply, and it is usually the start rather than the run that trips a circuit; controlling that draw is what keeps the machine on a standard supply. Amperage is switchable between fifteen and twenty at the controller, so it matches the circuit it finds rather than requiring one.

Adjustable weights and variable speed cover the range of work. Loaded and slow, it takes off thin-set, coatings and adhesive; light and fast, it polishes to three thousand grit. That span is why one machine handles both a small job and a large one instead of the fleet needing both ends.

Common Applications

  • Preparing concrete for overlays and coatings
  • Removing thin-set, coatings and adhesive
  • Polishing concrete to a 3000-level finish

Selection Notes

  • Amperage switchable between 15 A and 20 A at the controller
  • Ships with couplers, quick-change assemblies, adapters and hex keys
  • Three quick-change assemblies and three velcro adapters are required for a full set
Capacity
Disk size
18.5 in (47 cm) Confirm with supplier
Polish level
Up to a 3000-level polish
Drum speed
133.8 RPM
Motor speed
400 to 2,000 RPM
Unit Specifications
Motor
3 HP (2.24 kW)
Motor phase
Single
Voltage
115 V Confirm with supplier
Frequency
60 Hz
Amps
15 A or 20 A, switchable at the controller
Build
Soft start
Built in, controls amperage draw
Weights
Adjustable
Speed
Variable
Accessories
Morflex couplers
401882, supplied
Quick-change magnetic-mount assembly
9241, three required with three 73250 mounting screws
Velcro adapter
9245, three required, mounts on the 9241 assembly for polishing pads and brazed disks
Hex key
73135, 5/32 in
T-handle wrench
6280-401B, 7/32
Dimensions & Weights
Weight
388 lb (176 kg)
Width
20 in (51 cm)
Maximum height
52 in (132 cm)
Minimum height
27.5 in (70 cm)
Maximum length
75 in (191 cm)
Minimum length
38.5 in (98 cm)
Built-in soft start
A heavy head starts without tripping the standard circuit it is plugged into
Switchable 15 A or 20 A draw
The machine matches the circuit it finds instead of requiring one
Adjustable weights with variable speed
One machine covers coating removal and 3000-grit polishing

Included with Purchase

  • 1 8274-4 Planetary Grinder (variant/model as ordered)
  • 401882 Morflex couplers
  • 9241 quick-change magnetic-mount assembly
  • 9245 velcro adapter
  • 73135 hex key
  • 6280-401B T-handle wrench

Not Included Unless Stated

  • Diamond tooling, polishing pads and brazed disks
  • Dust collector
  • On-site installation or machine configuration

Note: Confirm exact included components and mount hardware with supplier at time of order.

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