Power Tool Buying Guide for Rotary Hammer

Bosch Cordless Rotary Hammer Review

What Is a Rotary Hammer?

A rotary hammer is a heavy-duty device built to drill or chip through concrete, stone, masonry, and other hard materials. It combines rotation with a powerful hammering action that pulverizes whatever is in its way. If you’ve tried drilling into concrete with a standard hammer drill and burned out your bit or your patience, this is the upgrade you needed yesterday.

Rotary hammers are a must-have for anyone who works with concrete anchors, demolition, or rough-in installations.

History of the Rotary Hammer

The rotary hammer was introduced in the early 1930s, with Bosch being one of the pioneers in making this a reliable, jobsite-ready machine. Over time, SDS (Slotted Drive System) and SDS-Plus shank systems were developed to make bit changes faster and increase durability under extreme loads. Rotary hammers quickly became the go-to for concrete professionals, replacing older impact drills and manual chisels.

What It’s Used For

Rotary hammers are made for serious drilling and breaking. You’ll typically use them for:

  • Drilling anchor holes in concrete or stone
  • Chipping out old mortar or tile
  • Breaking up concrete slabs, steps, or footings
  • Driving ground rods
  • Setting rebar dowels in foundations
  • Cutting channels in block or brick for conduit and piping

What to Look for When Buying

Corded or Cordless

  • Corded: More power and better for constant use
  • Cordless: Great for mobility and smaller jobs—look for 18V or 36V options

Modes of Operation

  • Drill only: For wood or soft materials (not common on these)
  • Hammer only: For chiseling and demolition
  • Hammer + Drill: Most common mode for setting anchors in masonry

SDS, SDS-Plus, SDS-Max

  • SDS-Plus: For light to medium-duty work, most common
  • SDS-Max: For heavy-duty concrete drilling and chipping
  • Spline drive: Older system, still used on a few models

Impact Energy

  • Measured in Joules or ft-lbs
  • Higher number = more powerful blows, not just faster drilling

Vibration Control

  • Important for comfort and long-term use
  • Look for anti-vibration handles or internal damping

Depth Stop and Variable Speed

  • Helps with precision drilling and avoids over-penetration
  • Variable speed trigger offers better control when starting a hole

Clutch Mechanism

  • Protects the motor and your wrist if the bit binds up suddenly

Pros and Cons

Pros

  • Rips through concrete, stone, and block with ease
  • Much more powerful than a standard hammer drill
  • Multi-mode operation adds versatility
  • SDS system makes bit changes quick and secure
  • Excellent for anchors, chiseling, and demo work

Cons

  • Heavier than standard drills
  • Overkill for soft materials like wood or drywall
  • Requires specialty bits 
  • Higher cost compared to hammer drills
  • Can be tiring for overhead or extended use

Bit Compatibility

Rotary hammers require SDS-compatible bits:

  • SDS-Plus: Light duty, holes up to 1 inch
  • SDS-Max: Heavy duty, holes 1 inch and larger
  • Chisel Attachments: Point, flat, tile, scaling chisels
  • Core Bits: For large diameter holes in block or concrete
  • Rebar Cutters: For going through embedded metal without overheating

Always check your device’s shank type before buying bits.

Safety and Maintenance Tips

  • Always wear safety glasses, ear protection, and gloves
  • Don’t use regular drill bits, they’ll break or damage the chuck
  • Let the bit do the work, don’t force it
  • Periodically grease SDS-Max bits if your model requires it
  • Watch for hidden wires or rebar before drilling
  • Keep vents and motor housing free of dust buildup
  • Store bits clean and dry to avoid rusting or sticking

Who This Is For

  • Homeowners doing concrete anchor installs or removing tile
  • DIYers taking on renovations involving block, brick, or stone
  • Pros in electrical, plumbing, HVAC, and concrete trades

If you’re working with any kind of masonry regularly, this belongs in your arsenal.

FAQ

Can I use a rotary hammer for demo work?

Yes. Most have a hammer-only mode and work great for tile removal, light concrete breaking, or chiseling brick.

What’s the difference between a rotary hammer and hammer drill?

A hammer drill uses vibration to chip while rotating. A rotary hammer uses a piston mechanism that hits much harder, making it the better choice for masonry.

Is SDS-Max better than SDS-Plus?

Not better—just built for heavier-duty jobs. SDS-Max models are larger, heavier, and more powerful.

Final Thoughts

Rotary hammers are built for real work. If you’re dealing with concrete, stone, or block, a hammer drill won’t last long and won’t get you far. With the right mode, bit, and approach, a rotary hammer can handle everything from drilling anchor holes to busting out old slabs. It's one of those investments that pays for itself in time and less frustration.