# Drilling deck pan filled with concrete



## Toronto (Jun 22, 2009)

Hey all I'm wondering if any of you have some tips on drilling into decking filled with concrete. 
I have to build a rack and have to use 1/2" rod with 5/8" drop in anchors. What I'm doing now is drilling a 1/8" sds pilot, then using a 7/8" metal hole saw to remove the steel, THEN finishing it off with a 5/8" sds bit 
I have about 140 of these to holes to drill 
Although very time consuming, this hole saw method works but if I drill past the steel into the concrete even for a split second I ruin my bits. 
So if anyone here can request an easier way to do this it would be much appreciated.


----------



## Awg-Dawg (Jan 23, 2007)

Drill thru the decking with the bit. 

You dont need to cut the deck or pilot the hole.



Edit: I must have missed where you said you did this already.

I do it all the time without a problem.


----------



## Toronto (Jun 22, 2009)

I normally do just drive the sds through the deck but this particular decking is thicker gauge. I'd say double the thickness of what I've seen elsewhere


----------



## Awg-Dawg (Jan 23, 2007)

Toronto said:


> I normally do just drive the sds through the deck but this particular decking is thicker gauge. I'd say double the thickness of what I've seen elsewhere


 I realized you were in canada after I posted.

I thought maybe you have differents codes there about thickness.

When I see decking like that, there is usually bar joists, you dont/cant use them?


----------



## 360max (Jun 10, 2011)

just drill 1/4" hole and let the sds bit do the rest, it will save your holesaw from the concrete


----------



## Cow (Jan 16, 2008)

When I had to hang a trapeze from pandecking, I used 3/8" redhead wedge anchors. I'd punch through the steel with the rotohammer bit and up into the concrete. Drive a wedge anchor in, tighten it down, and then install a rod coupling on the end of it to hang the allthread from. 

I assume a 1/2" rotohammer bit would punch through the steel as well. 

It also reminds me that I don't miss that job. Overhead drilling with concrete dust in your face plus it was LOUD drilling through the steel.:no:


----------



## Toronto (Jun 22, 2009)

Thanks of the replies. I figured there would be no other solution other than what I have tried. The 5/8" sds bit just doesn't pierce the pan decking without jamming the bit. 
As for the dust, I'm using a dewalt 36v cordless sds with a hepa vac attachment, best invention ever atm for me! Not an ounce of dust gets past it.


----------



## JohnJ65 (May 8, 2008)

Do yourself a big favor and wear some hearing protection while drilling that steel so your not wondering what everyone said the rest of your life.


----------



## Expediter (Mar 12, 2014)

JohnJ65 said:


> Do yourself a big favor and wear some hearing protection while drilling that steel so your not wondering what everyone said the rest of your life.


What???




:laughing::whistling2:


----------



## Expediter (Mar 12, 2014)

It might be that a different carbide sds bit is in your future. I always just drill the proper size sds bit through the steel decking and on into the concrete, no changing bits. Leave it on impact, don't try to act as if it is a HSS bit. Some bits are more rounded than others, and don't have the cutting action you need to work the steel away.

Glasses and hearing protection is a must.


----------



## CopperSlave (Feb 9, 2012)

Not sure how much weight will be on your rack but, I'd take a look at using a Ramset to fasten some strut to the deck then, use spring nuts to suspend the rod with....if that would be feasible.


----------



## B-Nabs (Jun 4, 2014)

How about fastening a 1/2" ceiling flange with a couple of 1/4" wedge anchors or even smack pins then threading the allthread into that?


----------



## Toronto (Jun 22, 2009)

This rack is for two runs of 4" rigid and some future conduit as well. Has to be 5/8" rod


----------



## 360max (Jun 10, 2011)

Toronto said:


> Thanks of the replies. I figured there would be no other solution other than what I have tried. The 5/8" sds bit just doesn't pierce the pan decking without jamming the bit.
> As for the dust, I'm using a dewalt 36v cordless sds with a hepa vac attachment, best invention ever atm for me! Not an ounce of dust gets past it.


again, drill a 1/4" hole, run the SDS bit with light pressure and allow it to eat thru the metal deck, than start applying normal pressure for concrete. Use of a *Hilti* drill goes without saying.


----------



## danhasenauer (Jun 10, 2009)

A diamond tipped hole-saw will last forever, if it doesn't get stolen from you. Not too expensive if you factor in labor time saved. Needed one for a similar situation once (heavy gauge sheet-metal backed by concrete), still using it 10 years later. But, yeah, we usually run the SDS right through the pan here.


----------



## Toronto (Jun 22, 2009)

Can you give me an example of a diamond tipped bit? Is it like the ideal bits that are spring loaded to remove debris?


----------



## Dennis Alwon (May 9, 2009)

CopperSlave said:


> Not sure how much weight will be on your rack but, I'd take a look at using a Ramset to fasten some strut to the deck then, use spring nuts to suspend the rod with....if that would be feasible.


That was my thought. Some place do not allow them but if you have alot of holes this is the way to go. I assume a purple charge but I would start lower and test. I have used purple charge in steel beams.


----------



## Southeast Power (Jan 18, 2009)

First thing I thought of is if you could core drill the size hole you need from the floor above and then patch the holes after you install the anchors.


----------



## Southeast Power (Jan 18, 2009)

Dennis Alwon said:


> That was my thought. Some place do not allow them but if you have alot of holes this is the way to go. I assume a purple charge but I would start lower and test. I have used purple charge in steel beams.


I have shot several hundred 3/8" studs with a HILTI 451 DX. 
It is a beast and has no problem with placing a stud in steel/concrete. I don't think I would be anything to replace the size anchors they specified for you.

I would think they Hilti has a product that would work.
I was also thinking of a holesaw with a depth stop .
I guess this is why they use steel and concrete for constructing safes.
It's a tough mix.


----------



## Southeast Power (Jan 18, 2009)

Toronto said:


> Can you give me an example of a diamond tipped bit? Is it like the ideal bits that are spring loaded to remove debris?


Kinda like a core bit but smooth.


----------



## freeagnt54 (Aug 6, 2008)

Try the bosch bulldog xtreme bits, they have a full carbide head and can cut through rebar. I would imagine they can handle the deck pan.


----------



## Locknutz (Sep 7, 2012)

I like 360's idea but if you have a helper or a second hammer drill go through and pre drill with a 1/4" sds just through the decking and touch the concrete. Then follow with the 5/8". 

The 1/4" steel bit would be cooked as soon as it hit the concrete as well.


----------

