Originally Posted by 26yrsinflooring
A hammer drill with a chisel bit loud dusty heavy thingy...
Good set of work gloves, dust mask and plenty of time......
I don't want to change the topic of this thread...
I just want to put in this blurb for any newbies that might be reading this thread and wondering if they can do this kind of work if they just bought one of the new cordless hammer drills they've seen at Home Depot.
There are different kinds of "hammer drills". The corded or cordless hammer drills that look very similar to corded or cordless regular drills are called "percussion" type hammer drills, and my guess is that they would be totally useless in trying to remove thin set from concrete (even if they did have a "hammer only" mode, which they almost certainly won't). These drills work OK in softer masonary materials like brick, mortar, concrete blocks and soft rocks like limestone or marble, but they're not made for drilling into harder materials like concrete or harder rocks like granite. Typically, these percussion type hammer drills use an ordinary drill chuck to hold a special "masonary" style drill bit (that has a characteristic tungsten carbide chip at it's business end).
The kind of hammer drills made for drilling into concrete and hard rock are called "rotary hammers" and they have a piston and cylinder arrangement inside them that moves the drill bit back and forth 1/8 of an inch (or so) with each rotation of the drill bit. That essentially "batters" a hole in the masonary, and the spiral flutes are there to remove the crushed material.
26yearsinflooring was referring to a "rotary hammer" which is a kind of hammer drill. Think of it as a percussion type hammer drill on steroids.
Rotary hammers can't use a regular drill chuck because key-type chucks are press fit together and the hammering action of the rotary hammer will shake a regular drill chuck apart. Rotary hammers will most commonly use something called an "SDS" chuck, which was introduced by Bosch and stands for "Insert, Twist, Stay", but in German those words translate to "Steck, Dreh, Sitz", hence, SDS. For marketing purposes internationally, Bosch uses the SDS to stand for "Special Direct System" which kinda says and means nothing at all, kinda like Barack Obama's "Change We Can Believe In". (What, really, does that mean? Anyone know?)
This web page shows the cross sectional view of an SDS chuck:
SDS chucks don't open and close like a regular drill bit chuck to accomodate the size of the drill bit. Instead, a set of SDS masonary drill bits will have different diameters but the ends will all be the same size to fit properly in the SDS chuck. You insert the drill bit and then rotate a collar on the drill chuck 1/4 turn. This causes two ball bearings to fit into two short grooves in the end of the drill bit. That design allows the chuck to firmly twist the drill bit, while at the same time allowing it to move forward and backward with every rotation of the bit. It's the fact that the drill bit has a powerful hammering action to it that allows rotary hammers to drill into hard masonary so much faster than percussion type hammer drills (where the drill bit just kinda "shakes" back and forth an ever-so-tiny bit).
Most rotary hammers ALSO have a rotate only and hammer only mode on them so that you can use them to drill into wood or steel, and as electric chisels.
And, you probably won't find a set of SDS regular twist drill bits for drilling into wood or steel. That's cuz such a set would cost more than an "adapter", which is best described as an ordinary key-type chuck mounted on the base of an SDS drill bit.
You put the rotary hammer in "rotate only" mode, put the adapter in the SDS chuck, and then put an ordinary drill bit in the adapter so you can use the SDS rotary hammer in rotate only mode to drill holed into wood or steel using much less expensive ordinary twist drill bits. (that is, non-SDS drill bits)
You can also get bigger hammer drills that use a spline drive so that the bits have splined ends, but I know squat about them.
So, not all "hammer drills" will do the kind of work 26years is talking about.