Makita has announced a new addition to their line of concrete rotary hammers, a two-inch model with enhanced Anti-Vibration Technology (AVT). Earlier this year I saw the 1 9/16-inch version of the tool demonstrated at the World of Concrete (video below) and the AVT appeared to greatly reduce vibration.
According to Makita, many rotary hammers rely on spring-loaded handles to take care of vibration. Their AVT tools rely on a three-component system that deals with vibration in ways simple spring-loaded handles cannot:
An air actuated counterbalance dampens vibration by moving in the opposite direction of the drive piston.
The upper housing and handle move independently because they’re decoupled from the motor and drive mechanism.
There is a damper spring at the base of the impact bolt to absorb impact vibrations from the drill bit.
Features include a torque-limiting clutch, soft start, and constant speed control to maintain even speed under load. The two-mode tool has “hammering with rotation” and “chipping only”, with the option to lock the tool on in chipping mode. It offers 24 bit angle settings and a one-touch sliding chuck for fast bit changes.
Makita HR5212C Specs
Motor: 15 amps
Capacity in concrete: 2”
Impact energy: 19 joules (14 ft-lbs)
Vibration rating: 9m/s²
Blows per minute: 1,100-2,250 BPM
Bits: SDS MAX
Length: 23 1/2”
Weight: 26.2 pounds
Includes: rotary hammer, depth rod, bit grease, D-handle, straight handle, and straight handle assembly
Country of origin:
Web price: $1,100-1,200
Available: October 2014