Drilling Concrete

[Bill Tattersall]

Hi All. Anyone have some tips on drilling concrete? I'm putting a 2 post lift in my shop and need to drill 10 3/4 x 5 deep holes for the anchors. My Milwaukee drill that I have used on smaller holes in the past doesn't seem up to the task. Am I doing something wrong or am I better off just renting a larger unit?

 

[timcasbolt]

I was able to borrow one from work, but yea, rent one.

 

[Janicholson]

Real hammer drills should be rented unless you have at least a simianual need to own one. They will save your sanity/back/time/temper/drill. Jim

 

[Roger in Iowa]

Sharpening the bit periodically helps!

 

[wp6529]

Make sure to use a new quality bit and keep the drill perfectly straight i.e. don't let it wander or wallow out. Those anchors keep the lift from tipping over and dumping a vehicle on top of you.

Make sure to use top quality anchors as well, if the lift comes with unknown anchors, replace them with something like Hilti that you can rely on.

 

[Jim.ME]

You don't say what Milwaukee drill you have, is it a hammer drill?
do you have a good concrete drill bit or the local hardware store garden variety one? The right gear makes a big difference.

Rent a hammer drill (like a Hilti TE26 or larger) and get the right bit to go with it. If your slab has rebar, you want a bit that will cut rebar. 10 each 3/4'' x 5'' deep holes should take less time to drill than it takes to go get the drill and return it, unless the rental house is just across the street.

 

[Scott 730]

(quoted from post at 16:40:52 09/04/23) Sharpening the bit periodically helps!

???Huh??? In my 45 years in commercial building construction I have never heard of, or seen, anyone "sharpen" a carbide masonry bit.

 

[Charles in Aus.]

Buy a ' Quadcut ' drill bit of the correct size . Instead of the usual two cutting faces they have four This gives a faster , smoother and more stable cut with less chipping and cracking , The cutting face will also pass through reinforcing steel without binding and twisting your wrists off .

 

[unc]

(quoted from post at 14:30:17 09/04/23)

(quoted from post at 16:40:52 09/04/23) Sharpening the bit periodically helps!

???Huh??? In my 45 years in commercial building construction I have never heard of, or seen, anyone "sharpen" a carbide masonry bit.

Carbide masonry bits can be sharpened like a normal twist drill. The trick is to use a silicon carbide ("green wheel") grinding wheel, rather than the usual aluminum oxide wheel. They will cut like new and last much longer. unc

 

[Tony in SD]

As others have said rent a real hammer drill with 3/4 X 6 SDS bits or equivalent. The combo hammer/drill battery operated drills that have a hammer function are not made to drill 3/4 holes. Much less 10 holes. Tips: keep the drill plumb both ways or your bolt holes wont fit. Dont push for he drill, the weight of the drill is usually enough down pressure. Lift the drill often to clean the concrete dust from the holes. If you dont the concrete dust will bind the bit and your bit will be stuck, very stuck. BTDT

 

[Ultradog MN]

Do you want to get ten holes drilled in 10 minutes or fart around all day?
As a couple of others have suggested, go rent a hammer drill.

 

[Stephen Newell]

Are you using a Milwaukee drill bit with your drill? Is it also a hammer drill? I use a Milwaukee hammer drill and could probably drill the holes in 15 minutes.

 

[Stephen Newell]

Buying a hammer drill is one of the best things I've done. I only drill in concrete a couple times a year but the Milwaukee hammer drill I bought will drill through concrete as easy as my cordless drills through wood.

 

[Butch(OH)]

Agree with the hammer drill comments. Needed one 10 years ago, checked on a rental and for the price of renting one for two days I went and bought an SDS shank hammer drill and bit set to 3/4 at Harbor Freight. It has drilled 100s of holes for me and family and still works sane as first day and best of all when I need it all I have to do is get it off the shelf, no two trips to town, no wait. Just something to think about if you ever have need past this project

 

[504]

$129.00 for a decent one at Harbor Freight,400.00 will get you a fancy one. THe last time I needed a one for a big job I rented one,but I have no idea what it cost.

 

[buzzinduzzin]

you have in floor heat ?

 

[moresmoke]

I have a cheapie SDS rotary hammer drill from Northern Tool. It paid for itself on the first job and has been used a couple times a year for 10 years.

 

[john in la]

While most people lump both types into one category....

If I was drilling 3/4 inch holes 5 inches deep in concrete I would be looking for a 'Rotary Hammer' and leave the Hammer Drill for mounting a hose real into brick mortar.
Also get a bit long enough you can stand up and hold the drill.
Getting a 3/4 bit stuck in concrete chucked into a drill strong enough to do the job while you are down on the floor messing with a homeowner hammer drill and a short bit is a recipe for a broken wrist.

Hopefully you planned ahead and you have concrete footers big enough to support the weight of this lift already in place.

 

[Blackhole49]

Rotary hammer is the only way to go.

 

[showcrop]

(quoted from post at 14:30:17 09/04/23)

(quoted from post at 16:40:52 09/04/23) Sharpening the bit periodically helps!

???Huh??? In my 45 years in commercial building construction I have never heard of, or seen, anyone "sharpen" a carbide masonry bit.

X2