Cut-Off Machine Buyers Guide
A good cut-off saw can only be appreciated by those who have the opportunity to tear though a big piece of concrete with something that sounds like a hand held dirt bike!  

Cut-Off demolition saws are used for cutting concrete and metal with abrasive wheels. These machines couple a high power engine with a fast spindle and wheel to quickly cut though very hard material. Buying the right tool for the application is critical. More powerful machines are able to make quick work of large jobs. Advanced filtration and water jets address the dust cloud the forms around the operator, and diamond and abrasive cutting wheels need matched to the material that's being tackled.
  • Cutting Wheel Size A larger cutting wheel is able to cut though thicker material. Typical sizes are 12-20". Larger is not always better as bigger wheels often don't run at the same high speeds as smaller ones.
     
  • Cuttings Wheels need to be matched to the application. The most common wheels are simple abrasive wheels for stone or metal. Diamond blades are 5-6x the cost of simple abrasive blades but are needed when cutting the hardest materials.
     
  • Water Attachment is a must have feature for cutting anything other than metals. Stones and concrete turn to dust when cut with an abrasive wheel. A water jet in the cutting area helps lubricate the cut and control dust levels that can choke out air supply of both the saw and operator.
     
  • Engine displacement is a measurement of the size of the engines cylinders. Typically a saw with more displacement has more power. Today this logic is skewed some as many saws will share a common engine, but by tweaking compression and fuel ratios the manufactured can change the true power output. The most reputable brands publish both engine displacement and horsepower so you know what your getting. Because of the enormous amounts of power needed in this application some saws use more advanced ignition systems to help get the most out of the engine.
  • Decompression Lets the pressure out of the engine cylinders when starting a saw. It makes it much easier to turn over the engine when you are not fighting the compression of the engine.
     
  • belt-adjustment features keep tension on the drive belt that runs between the engine and cutting wheel.
     
  • Air Systems are offered on some saws to help keep the air cleaner free flowing in dusty conditions. Do not underestimate the ill effects caused by a clogged air filter.
     
  • Carts are optional on some models for wheeling the saw forward for long straight cuts. Some have optional water tanks for running the saw where a hose is not available.
     
  • Weight is an important consideration when hand holding a cut off saw. Most units weigh 20-30lbs and can get difficult to handle. Overhead cuts and wall work are best done with smaller saws that can be held more precisely for longer periods of time.