hammer drills- any tricks to know ?
 

I have two holes I need to drill in a concrete driveway about 5/8-3/4 in diameter. I have a HD 1/2 " drill with a 5/8 carbide masonary bit and the concrete just laughs at it ! So I'm thinking I need to get/rent a hammer drill. Do hammer drills use conventional masonary bits or something more exoctic ? Any tricks to using these ? I want to drill the holes maybe 3 " deep if that matters.

I used a small hammer drill to drill one hole in a concrete stem wall. It took forever. I went to the rent all place and rented a real deal hammer drill. It took longer to drive to the store than that thing took to drill the hole. It rented for cheap. They had the drill bits at the rental place.

You need a big hammer drill for the holes you describe. Yes they take special bits.

Home Depot will have what you need.

I have a 1/2" hammer drill but my choice would be this ^ for drilling 3/4" holes.

The bits will come with the drill. Don't go too fast, a hammer drill and a good bit will fly through the material sometimes. Hold on to the drill and don't let it get away from you.

yeah man. You are going to want a real hammer drill for that. Just go rent one.

Rent the right one and it will be like cutting soft butter. Just don't hit any rebar...

Hilti

Rent it - ask for a rotary hammer, not a hammer drill. Big difference. Hammer drills are good if you're drilling small holes for nylon anchors or tapcon screws. Rotary hammers are best for stuff that size.

Are you drilling straight down or into the side? If down, be patient and let the weight of the drill push in. Don't kill your shoulder by pushing down on it. Sharpness of the bit is irrelevant, you need one with good carbide.

I have a normal small battery operated hammer drill. Using from smaller to bigger masonary bits usually fine, but sometimes it just won't go after a certain deep. I think it got to a rock or a metal rebar. When that happen, nothing I can do beside burning the bit's tip.

One of the few things I've ever bothered with from Harbor Fright is the $50 rotary hammer drill that accepts the Bosch SDS concrete bits. Ridiculous bargain thats been used often, loaned out and always works like it should. It came with spare motor brushes, various chisel ends, small bits but I added a set of SDS larger bore bits for approx. $20. The only thing too el-cheapo was the side handle made of plastic. That went to the garbage so I turned on the lathe a knurled aluminum handle. I also wrapped in duct tape the entire plastic motor housing to protect it from the usual banging around on job sites. Figured it was a disposable tool but has been holding up for at least 7 years!

Just looked at the HF site and I see they raised the price substantially. Mine is the older orange colored but the same unit. A steal.
http://www.harborfreight.com/3-in-1-1-inch-sds-rotary-hammer-97743.html

Use a smaller bit first and then use the 5/8.

What Peppy said. Use a 1/4" drill. Get a Bosch or Milwaukee or some industrial drill bit. If not, you are wasting your time, Chuck it up to a hammer drill and have a go at it. Once the 1/4" hole is drilled and go after it with the correct size drill bit. If you are going to rent, get a roto hammer.

You wont need to drill smaller holes just go rent a rotary hammer drill. It will take longer to plug it in, then to drill the holes. 3/4" is not a very big hole for most rotary hammer drills.

Make sure whatever you get has a side handle for better control. When I was a carpenter I had to drill holes in morter and concrete often. I found out first hand that if the drill bit stops the drill will asume the duty of the bit and get a few good licks in before you can let go.

Thanks guys for the feedback I love this forum. Yes the holes are being drilled straight down.

LOL, been there done that.