[Mark Harvey]

I am drilling into a very old foundation and the standard concrete bits don't do anything. I'm using a hammer drill and the bits are from HomeDepot. I think they would do fine on brick and cment blocks but the foundation is solid. Any suggestions?

 

[joecaption]

Sure the drills running in the right direction?
Unless I'm hitting a stone in concrete I've never had on not work.
What size hole?
What drill are you trying to use?

 

[Mark Harvey]

drill bits

I'm using a Dewalt 1/2" also I have a local brand Mastercraft hammardrill. The hole size is 3/16. I agree I may be hitting a rock but I would think it would shatter after a while.

 

[oh'mike]

Try Bosch masonry bits---they are the best ones you will find without going to a specialty house---

I use them all the time and go through some tough materials----

 

[princelake]

if the bosch bits dont work get yourself the hilti rotary hammer drill bits and just put it in the chuck of your regular hammer drill.

 

[user1007]

Sounds like you need something like the bits mentioned. Your real tool supplier will have carbide and diamond tipped masonry bits. Might be worth it since 3/16" is a size you will use a lot I suspect.

Are you able to get into the surface at all. If so, are you sure you are not hitting steel rebar, plate or something as you go? A masonry bit will not help much with that!

 

[Thurman]

"using bits from Home Depot". Home Depot sells a number of brands of so-called "masonry bits". A good, known brand, such as the Bosch mentioned may be the answer to your problem. Now--is the DeWalt 1/2" drill a "hammer drill"? I'm not familiar with the Mastercraft, so I can't judge it. You will need (can we say "must have") a good hammerdrill to do this job. I have drilled into a lot of old concrete and I don't know whether it was because of it's age or mix back then, but they are harder than today's concrete. 1) A good, brand name, carbide tipped masonry bit, and 2) a good, preferably brand name, hammer drill should drill into this concrete. Granted that a stone or re-bar will make the job harder. Someone with experience can tell if they are hitting a stone or a metal re-bar, but both can be drilled through with the proper tools and procedure.

 

[Mark Harvey]

bits

Great advice from all. The tool I mentioned "Mastercraft" is from a company called Canadian Tire. I din't think they have entered the U.S. market but I'm sure you have similar companies. They aren't bad, but I consider their tools to be mostly throw away after use. I may have to invest in a good hammer drill ... Bosch, Dewalt, etc. but as my use for a hammer drill is limited, it's one of those investments to think about.

 

[woodworkbykirk]

hte mastercraft tools hes talking about are known as kobalt in the u.s

come from the same manufacturere im pretty sure just get a differnt brand tag

 

[stadry]

NEVER use a rotary-hammer / hammer-drill w/diamond bits UNLESS you have deep pockets - you'll destroy them in a heartbeat,,, we routinely use apron / vest store 3/8" carbide bits w/sds chuck for epoxy crack injection - never any troubles - they're cheap & we can always find an apron / vest store for more :thumbsup:

 

[jomama45]

Heck, I've never even heard of a "diamond masonry bit", other than core bits that would fit in a huge core rig. I highly doubt you're going to find a diamond core bit at 3/16" though...........:whistling2:

As others said above, buy a decent carbide tipped SDS bit, and carefully chuck it into you're drill. It may take a few times tweeking the orientation in the chuck to keep it from wobbling.

 

[user1007]

Heck, I've never even heard of a "diamond masonry bit", other than core bits that would fit in a huge core rig. I highly doubt you're going to find a diamond core bit at 3/16" though...........:whistling2:

I have one 1/4"d. It is a core bit but fits a standard drill chuck.

 

[jomama45]

I have one 1/4"d. It is a core bit but fits a standard drill chuck.

I'd LOVE to see a picture of a 1/4" diameter diamond core bit...............:whistling2:

 

[user1007]

I'd LOVE to see a picture of a 1/4" diameter diamond core bit...............:whistling2:

They are sold as masonry, concrete and tile bits. I have used mine mainly for drilling into masonry and concrete to fit anchors for hanging art. Has always worked flawlessly. I see there is a 3/16" bit for about $15.

http://dewalt.com/tool-parts/drilling-accessories-concrete--masonry-drilling-diamond-tile-bits.aspx

 

[oh'mike]

Look on E-bay I use a lot of 1/4" hollow diamond bits-----I get them from Hong Kong for about $15.00 a dozen.

Use them for drilling porcelain tile.

 

[jomama45]

They are sold as masonry, concrete and tile bits. I have used mine mainly for drilling into masonry and concrete to fit anchors for hanging art. Has always worked flawlessly. I see there is a 3/16" bit for about $15.

http://dewalt.com/tool-parts/drilling-accessories-concrete--masonry-drilling-diamond-tile-bits.aspx

Those are tile bits, and I doubt they have enough length for what the OP is doing.

This is what a concrete/masonry diamond core bit looks like:

http://www.hmabrasives.com/images/Diamond-Core-Drill-Bits-CBAA-.jpg

 

[user1007]

Those are tile bits, and I doubt they have enough length for what the OP is doing.

You may well be right but the OP has not told us what he is trying to accomplish with such small holes in a foundation? As mentioned, the bit I have works just fine in masonry and concrete for drilling holes into which screw anchors go to hang art.