Drilling into concrete garage floor

[CoarsegoldKid]

I'm needing information/ your experience on drilling into concrete. I'm mounting a tire changer and the instructions say use 3/4 masonry bit and a 3/4 lag shield.

I've tried to drill 3/4 holes into concrete before using my 18 volt 3/8 drive and although I did get a hole it wasn't pretty. I tried one hole with the 3/4 and it just destroyed the bit. Next I used pilot holes working up to 3/4. But when it came to the 3/4(new) bit I was only able to do little better. In fact some of the holes wouldn't go deep enough and the two 3/4 bits I used were destroyed.

Is there a better way?

[Twisties]

Use This - Problem Solved

[Firefight911]

You need a mason bit and a hammer drill. It is amazing the difference you will see as soon as you go at it with the hammer drill!!!!!

[mrduck]

Your cordless drill is not gonna work on something that big. Try the rental yard for a hammer drill, get a new bit, and don't force the bit with a lotta pressure! Let the drill do the work or you'll just melt the end off the bit.

 

 

 

Cheap advice from someone who does this alot!

 

 

Hi joe

[LandonBlueRT]

Your cordless drill is not gonna work on something that big. Try the rental yard for a hammer drill, get a new bit, and don't force the bit with a lotta pressure! Let the drill do the work or you'll just melt the end off the bit.

 

 

 

Cheap advice from someone who does this alot!

 

+1, from another with experience.

[ESokoloff]

I'm needing information/ your experience on drilling into concrete. I'm mounting a tire changer and the instructions say use 3/4 masonry bit and a 3/4 lag shield. (snip) Is there a better way?

 

To start with, I recommend using a 3/8" Drop-in-Anchor.

That way the drill size is only 1/2" & 4 of them should be plenty strong enough for the task as I'm sure that drop ins are stronger then lags.

This is what I did for the base of my NoMar. I had to use oversized washers on the 3/8" bolts though.

 

Perhaps you could make a non hammer type drill work but an impact type drill is the proper way to do it.

[fatboyjim]

Use This - Problem Solved

 

Yup, and I'd use a polyester Resin fix on thread studs too.

 

Pluside is once it cures it becomes part of the floor.

 

Downside is once its cures it becomes part of the floor.

[mickey05]

+1 on the drop in anchors. Shields will loosen up after time.

 

[Calvin (no socks)]

I have installed 6 auto lifts at the dealership. I went to a pawn shop and purchased a hammer drill and several bits for $40.00. I used it and then sold it back to the pawn shop 2 weeks later... Or you could rent one..

[Foot]

Try to find some that carries a chemical anchor in your neck of the woods. they won't loosen up over time and won't stress the concrete the way standard anchors do.

 

Alan

[CoarsegoldKid]

Thanks guys. What I ended up doing is renting a 1/2" drive Milwaukee hammer drill. I bought a 3/4" bit made for concrete and hammer drill use. I used pilot holes to make sure I was at least centered on each hole. A friend poured water at the hole to cool off the bit. I was able to get three holes out of four and it was a very difficult task. Not easy. I thought I was drilling rebar. The holes were not uniform but the tire changer will stay put.

 

 

[AviP]

+1 on the hammer drill. Skip the cordless version. BTDT.

[Twisties]

Next time SDS!

 

 

[bakerzdosen]

Well, I read a thread that (I think David started) talked about the topic a while ago. I decided to just give it a go with my Dewalt 18v cordless drill (with a hammer drill setting - which made a little bit of difference).

 

Suffice it to say, it worked. I did one hole a night, dropped in the anchors, and everything was fine.

 

HOWEVER, it took a LONG time to drill through. YMMV.

[Twisties]

Yeah, well I've done ordinary drill w/ masonry bit, hammer drill w/ masonry bit, cold chisel and 3 lb sledge, air hammer with chisel, and last time the HF SDS drill with SDS bit. All this on various masonry/cement projects.

 

My reaction to the SDS drill: Holy Crap Batman!, as they say.

 

Here's a LINKY

 

This thing will bore a hole in about 5 seconds in the hardest concrete you've ever seen. No drift, nice clean hole. Effortless. Fast. Amazing. For $59 it's a total no brainer. Happy to lend you mine next time you have a need.

 

Jan