When purchasing a rotary hammer, they come with either SDS, SDS-Plus
or SDS-max. I understand SDS-max is a different slot system, but
there seems to be no visible difference between SDS and SDS-plus. Is
Also, what does the size mean in a rotary hammer? For example a <1"
SDS-plus® BULLDOG Xtreme Rotary Hammer> what does the 1" mean? It is
totally unrelated to the actual bit sizes, I mean you do not buy a bit
that is rated for a 1" hammer or a 7/8" hammer, so what is the
significance of the size of a hammer?
SDS max is a much bigger diameter, for bigger hammers and rotary hammers.
I think SDS-Plus is alightly bigger than plain SDS.
I believe it's the size of the hole the motor is equipped to drill in
concrete, long term.
Not 100% sure, but that's what I surmise.
Having said that, I have the Bulldog, and it is a very capable tool --
But, unless you are doing a lot of hole drilling, you might be better off
with the pistol grip equivalent, which is much more ergonometric for most
drilling, and packs a helluva wallop, as far as hard concrete goes.
Colbert may be right about HF stuff, but you have to be careful about the
type of hammer. "Hammer drills" typically have 15-20,000 bps (bumps per
second), and even quality ones (milwaukee, porter cable) will handle only so
much hard concrete/stone.
"Rotary Hammers" have many fewer bps, typically about 5,000, but each "bump"
carries significantly more stone-breaking energy in each bump. What could
take a hammer drill 5-10 minutes of supreme effort (and probably numerous
wasted carbide bits) will take 5-30 seconds with a bulldog or equivalent.
Night and day.
HF stuff is OK, if the applications are not critical or demanding. I have
bought a lot of HF stuff, and am quite happy with their winches and a couple
of other things. Their close-quarter drill is OK, comes in handy. But you
will most likely appreciate the Bulldog if you have real work to do.
Oh, since I have both handy:
The D-handle bulldog (11224 VSR) is 0-1100 rpm, 0-6150 bpm, 6.9 A.
The pistol grip Bulldog is subnamed RotoHammer (11250 VSR), and is 0-1350
rpm, 0-6,000 bpm, 6.0 A.
Both come with a rotatable siide handle. The D-handle comes in a metal
The pistol grip was hard to find, and I wound up getting a display model
with no cord for $35 from HD. Don't know about a case for the pistol grip.
And speaking of HD, a good hardware store will beat HD prices by 10%, and at
worst will match HD.
It is said that stuff sold by HD is made *for*
HD, and made more cheaply,
and there is no way for the consumer to really know what's what. I won't
bet the farm on this, but I've heard this from a number of sources.
Either Bosch or Hilti, on either their lit or placards, list the energy per
bump in joules for each tool! For quite an accurate comparison. You'd
proly be hardpressed to find these numbers for the higher bpm hammer drills,
but I'll bet the numerical difference would be, uh, striking.