Description
Heavy road contractors require brute downforce to fracture reinforced concrete bridge decks. The Makita 70 lb. Advanced AVT breaker hammer generates 53.8 ft-lbs of impact energy through standard 1-1/8-inch hex bits. Motor input draws 15 Amps at 120 Volts. The 69-pound bare tool weight exhausts operators when prying broken concrete rubble out of deep foundation footings.
The impact mechanism couples an air-cushion steel striker to a mechanical counterbalance pendulum that strokes opposite the piston to cancel recoil forces. A heavy cast aluminum housing encloses the 15-amp motor armature, wound with heavy copper wire and coated in thermosetting zigzag varnish. The 1-1/8-inch hex tool holder utilizes drop-forged alloy steel heat-treated to 58 Rockwell C to resist shank peening.
Advanced AVT Breaker Hardware Platform
Active vibration cancellation mechanics decouple internal piston violence from the rubber shock-mounted side handles. Fixed-retainer hex chucks withstand heavy downward thrust against reinforced highway slabs.
- 15-amp industrial motor produces 870 blows per minute for heavy slab demolition.
- 53.8 ft-lbs impact energy fractures thick road concrete and bridge decks.
- Advanced AVT system cancels internal recoil using active counterbalances and housing isolation.
- 1-1/8-inch hex tool holder accepts standard collared or notched breaker steels.
- Soft-no-load function reduces motor speed when idling to reduce unnecessary vibration.
- LED service indicator lights signal brush wear eight hours before tool shutdown.
- Heavy-duty transport cart features large rubber tires for transit across demolition rubble.
Load Cell Impact Bench Telemetry
Ammeter logs record 14.6 Amps draw under continuous breaking in 6-inch 4500-PSI cured pavement slabs. Front barrel housing temperature rises to 154°F after thirty minutes of non-stop demolition duty. The striker delivers 865 blows per minute under heavy downward operator feed force. Internal crankcase lubrication temperature stabilizes at 162°F. Acoustic noise meters record 98 dBA at one meter during reinforced slab fracture testing.
Demolition Limits Fleet Service Directives
Do not use this heavy breaker to bury bits deep into soft clay without fracturing rock. Sinking the bit past the collar jams the chisel and overheats the impact mechanism.
- Apply high-temp chisel grease to bit shanks before every insertion into the hex chuck.
- Inspect the mechanical tool retainer latch and spring pin for cracks every week.
- Blow dust out of motor cooling vents and inspect carbon brushes every 50 operating hours.
Commercial Warranty Factory Package Items
Makita backs this breaker hammer with a 1-Year commercial warranty. Factory shipment includes the HM1812 breaker hammer, heavy-duty wheeled steel transport cart, two 1-1/8-inch hex bull point chisels, two flat chisels, hex wrench, and complete technical service documentation.
