The concrete around my window is incredibly hard, too hard for my non-hammer drill.
Somebody at Homebase advised me to buy this rotary hammer, which comes with special bits of 6, 8 and 10mm. He said I can use an adaptor for any smaller bits, forgetting to mention that in this case I cannot use the "hammer function" in this machine.
Indeed, this rotary hammer has 2 functions: drill and hammer. And I need to drill holes 4mm wide. So I need to use the machine's adaptor, and so I'm limited to the "drill" function.
My question is: considering that the "hammer" function is actually the extremely powerful rotary function which is only compatible with the special bits sold with the machine, does the "drill" function is similar to what a normal hammer drill does?
That's exactly what another Homebase employee said to me this morning, but I doubt it, because the "drill" function produces the exact same result as with my non-hammer drill.
Any second opinion would be welcome. The manual doesn't help at all, the brand doesn't seem to have a website (?). No idea where to ask.
Best Answer
As a remodeling contractor, I've owned both hammer drills and rotary hammers. The rotary hammers are frequently rated for drilling capacity by the diameter hole it can drill. Most homeowner chores can be accomplished by 7/8 to 1" capacity. You can drill larger holes, but at reduced speed.
There are 3 classes of SDS drills. The widest range of bits are in the "SDS plus" sizes. SDS max would be overkill.
I have and use an SDS-to-1/2 chuck adapter, which is rated for concrete drilling. I use it for the smaller sjzes only.
I would recommend getting a 3 function rotary hammer; - Drill only - Hammer only (useful with SDS chisels) and - Hammer + drill (my most used setting)