ᐅ Solid Calcium Silicate Block: Rotary Hammer or Just a Hammer Drill?

Hello everyone,

we are building a house using solid sand-lime bricks with a hardness of 2.0. It is often said that this type of brick is very hard, so my first choice was a rotary hammer. I am currently considering getting a Hilti TE 7-C or, as an alternative, a Bosch GBH 3-28 DFR.

I plan to use the machine for installing electrical outlets and other tasks that will come up now and later during the construction. While looking for a suitable drill bit, I came across information suggesting that a hammer drill might be the better option. With a hammer drill, you can also drill into sand-lime brick and install the boxes using a diamond core bit. The diamond bit requires the necessary rotations per minute, which a rotary hammer typically cannot provide. A hammer drill is also more precise. What surprises me is that Hilti no longer offers hammer drills. How do they address the issue of precise drilling, etc.?

Now I am a bit unsure... Should I go with a rotary hammer and a hammer drill bit, or rather a hammer drill with a diamond core bit?

What do you think?

Regards, CK

I would always use a rotary hammer, especially when you need to drill into concrete ceilings. I once tried it with a borrowed hammer drill (it remained just an attempt) and then bought a rotary hammer. Of course, it’s not suitable as the only drill, so I also have an 18V cordless screwdriver and a small one (Ixo) for minor tasks and assembling IKEA furniture.

You should not rotate a diamond core bit too quickly. A Bosch rotary hammer, whether a 2 kg or 3 kg (4.4 lbs or 6.6 lbs) model, is a good choice for this.

Yes, that is confusing. Some say you can and should drill the dia-drills slowly, but then I read in the Würth catalog that the dia-drills require at least 1,000 watts and 1,000 revolutions per minute. However, it seems like a rotary hammer drill would also work.