There are a variety of uses for Impact Rotary Hammers and to tackle those jobs you should understand the differences of different types of Rotary Hammers.
The first type is a standard Impact Hammer. This type of tool has no rotation but can be used for chipping and driving. If you are breaking up a small amount of concrete. Taking out an old wet bed mortar floor in a bathroom or driving ground rods 8 feet deep in the ground there are a number of job specific attachments that you can buy. Impact only hammers are often also called demolition hammers and are a step below a full sized jack hammer.
Rotary Impact Hammers provide both rotation and impact features and are something like a very large hammer dril. You can use large Standard drill bits and even larger core bits up to 6 or 8 inches in width to cut holes in concrete walls and slabs.
Another feature found on some rotary impact hammers is to run in 3 modes. Hammer only, Rotation only or both at the same time. Many manufacturers list this feature as Stop Rotation. Having this option will allow you to perform many more tasks including those of a standard impact hammer.
The visual difference between theses tools is very little. For the most part the only difference you will see is a setting on the head that will allow different modes of operation.
If you are purchasing an impact rotary hammer you should understand how you will use it and that will dictate which model you select. However for most people a Rotary Hammer with Stop Rotation will fit all of their needs.
Head Sizes
There are at least 3 different sizes: 3/4 , 1 and 1.5 inch however some manufacturers build off sizes. When selecting a tool you should make sure it fits the Bits that you need to use. If you are using larger core bits or chipper tools all day then you may only find those bits in a larger size shank or you may find that they cost less in one size or the other. Do your research because a full set of good SDS Bits will definately cost you more then the tool.
Bit Types
Most tools are using a standard SDS shank for attaching the bit to the head but there are other designs like Hex shaped. If you buy one or the other and need to use bits available only in the opposite shape shank then you are out of luck. If you are buying a new tool SDS is probably the best bet for getting a full line of attachments.
Corded Vs Cordless
Yes they actually do make cordless Impact Rotary Hammers if you can believe it. How many seconds they will run on a battery charge we have not tested yet and until we can find someone else willing to fork out a few hundred dollars for one we never will. Actually these models are really limited to the smaller bit sizes and their usefulness is limited to having a stronger cordless hammer drill. You can’t use these things all day or even for moderate size jobs but for a couple holes to run a service line into a house the are much better then dragging a generator and a corded one a few hundred feet out of your truck through the mud.
The YouRepair Store sells a full line of Rotary Hammers and Accessories at very low discount prices. Please visit our store and browse the features for more information about specific models.
Power Tools
Cordless Rotary Hammers
Corded Rotary Hammers