Core Drill. Anyone Used One

[d2dave]

I need to bore a couple of 50 mm holes into the side of my brick house.

I looked at hiring a core drill but I can buy a cheapie off ebay cheaper than half a days hire

I have however never used one. I looked at some youtubes and some have a pilot drill in the centre of core bit for guidance.

The ones on ebay don't seem to have this.

Any advice from users would be appreciated.

[p38arover]

Yep, I needed to bore a 1" hole through brick for conduit. One hole. The core drill was stuffed by the time I finished. Brick can be bloody hard. It was a cheapy drill from Aldi but it did the job. Two holes? Dunno.

[austastar]

Hi,
Not a core drill, but I had to put a hole saw through a fiberglass shower bay without a pilot drill (there was a tap in the way).
I cut a hole the same size in a piece of ply, (it does not have to be a round hole) and held that in place by hand till the hole saw had a good groove to run in, and then just finished the job with a light pressure.
A similar adaptation may work.
Cheers.

[d2dave]

Yep, I needed to bore a 1" hole through brick for conduit. One hole. The core drill was stuffed by the time I finished. Brick can be bloody hard. It was a cheapy drill from Aldi but it did the job. Two holes? Dunno.

Ron, did you do it wet or dry?

Was the drill machine or the core bit stuffed?

[goingbush]

I used 50mm SDS core drills at work , used to drill through slabs and occasionally hit reo , never wore the core bit out but burned out a few drill motors , Use them wet . They always had pilot drills

I had to drill 2 x 50mm holes at home after I finished at work and stupidly handed the SDS kit back before finding out it wasn't ever assigned to me , bought a cheapo 50mm core drill from eBay and it was impossible to use without a centre pilot bit so I bodged one into the core bit with lathe / welder , works a treat.

[fitzy]

I need to bore a couple of 50 mm holes into the side of my brick house.

I looked at hiring a core drill but I can buy a cheapie off ebay cheaper than half a days hire

I have however never used one. I looked at some youtubes and some have a pilot drill in the centre of core bit for guidance.

The ones on ebay don't seem to have this.

Any advice from users would be appreciated.

If there is no pilot you need to angle the bit to the work piece to start and then flatten out.
Sounds easier than it is though.
If you’re working vertically place the bit between your boots and lay it back.
If your horizontal cut a v into a 90x45 at the height you need the hole , lay back off this so only one quarter of the core is in contact with the wall, you will then drill a smiley face to get started.

[1950landy]

I have drilled a couple of 110mm holes through 150mm thick bricks with a core drill I bought on Ebay it came with a centering drill, driven by my Makita battery drill & no water to lube. I drilled as deap as I could from one side Then using a longer masionery drill bit the same size as the one surplied with the core drill drilled all the way through the brick so I had a correct center then using the core drill drilled from the other side. Lucky I have 3 batteries for my drill .

[rick130]

I've used core bits for years, and I can't imagine trying to use one without a pilot?
It'll wander all over the show, be bloody hard to start.

[scarry]

You can get a 50mm dry core for bricks from Trade tools,very cheap.

If it is a very old house,it will be slow going,modern brick,it will go through easy.

Cant borrow a rotary hammer for the job from someone?

Only other option is to hire(or buy)one.

And YES it has to have a pilot drill or it is useless.

[d2dave]

I have drilled a couple of 110mm holes through 150mm thick bricks with a core drill I bought on Ebay it came with a centering drill, driven by my Makita battery drill & no water to lube. I drilled as deap as I could from one side Then using a longer masionery drill bit the same size as the one surplied with the core drill drilled all the way through the brick so I had a correct center then using the core drill drilled from the other side. Lucky I have 3 batteries for my drill .

In my case I can't access both sides as it is an external wall on a brick veneer house.

I have loads of Makita 18 volt stuff with plenty of batteries including an SDS drill.
The core bits on ebay that come with an SDS adapter also have a pilot drill.
It is the ones that are designed to screw onto a one and a quarter inch core drill don't seem to have pilot drill.

As my holes are half the size of yours it should be a bit easier.

I was reluctant to go down the path of using a normal drill as my research has suggested that when it jams you risk serious injury,
one case of a broken wrist, whereas the proper core drill has a safety clutch.

I would prefer the Makita drill option though, as this will save me $100 on a core drill.
So, is it safe doing it this way?

[1950landy]

In my case I can't access both sides as it is an external wall on a brick veneer house.

I have loads of Makita 18 volt stuff with plenty of batteries including an SDS drill.
The core bits on ebay that come with an SDS adapter also have a pilot drill.
It is the ones that are designed to screw onto a one and a quarter inch core drill don't seem to have pilot drill.

As my holes are half the size of yours it should be a bit easier.

I was reluctant to go down the path of using a normal drill as my research has suggested that when it jams you risk serious injury,
one case of a broken wrist, whereas the proper core drill has a safety clutch.

I would prefer the Makita drill option though, as this will save me $100 on a core drill.
So, is it safe doing it this way?

I am not sure how much I shortned the life of my Makita drill but it is still working OK two years later. I had to go through the inside wall but because I was drilling a 110mm hole there was plenty of clearance for the drill body once I drilled through giprock on the internal wall. With a 50mm hole this may not be possable. I would think it would not be that expensive hireing a core drill & 50mm bit for the amount of time you will need it.

[d2dave]

I am not sure how much I shortned the life ofof my Makita drill but it is still working OK two years later. I had to go through the inside wall but because I was drilling a 110mm hole there was plenty of clearance for the drill body once I drilled through giprock on the internal wall. With a 50mm hole this may not be possable. I would think it would not be that expensive hireing a core drill & 50mm bit for the amount of time you will need it.

I do not need to go right through both walls. I only have to get through the brick to the wall cavity for electrical wiring.

I priced hiring one about six weeks ago. Don't remember how much, but it was more than the $150 I can buy a drill and bit off ebay.

So my question to you is this. Did you have any issues with it jamming and risking hurting your wrists when using in an ordinary drill?

If not, I will go down the path of an SDS adapter and just a bit.

[d2dave]

You can get a 50mm dry core for bricks from Trade tools,very cheap.

If it is a very old house,it will be slow going,modern brick,it will go through easy.

Cant borrow a rotary hammer for the job from someone?

Only other option is to hire(or buy)one.

And YES it has to have a pilot drill or it is useless.

Paul. House was built early to mid 80s.

Rotary hammer drill, Are you referring to one of the type that uses SDS drills. If so I have two of them. One 240v and an 18volt Makita.

[Bigbjorn]

Please use correct terminology, chaps. I wondered what you were on about drilling brick and masonry with a core drill. A core drill is used by a Machinist in a drill press, radial drill, milling machine, magnetic drill press to enlarge an existing hole to required size. Commonly a hole left in a casting by use of a core hence the name core drill. What you are using are annular cutters, rotary broaches, hole saws.

[W&KO]

Please use correct terminology, chaps. I wondered what you were on about drilling brick and masonry with a core drill. A core drill is used by a Machinist in a drill press, radial drill, milling machine, magnetic drill press to enlarge an existing hole to required size. Commonly a hole left in a casting by use of a core hence the name core drill. What you are using are annular cutters, rotary broaches, hole saws.

The concrete cutters I use call drilling holes into concrete core drilling...I’m happy with the terminology

[scarry]

Paul. House was built early to mid 80s.

Rotary hammer drill, Are you referring to one of the type that uses SDS drills. If so I have two of them. One 240v and an 18volt Makita.

Yes the one from trade tools is SDS.
But ring before you go as they are sometimes out of stock.
There are a few different sizes.

Just go slow you will be Ok,we have used them hundreds of times,using a Bosch cordless 36V rotary hammer.

[scarry]

The concrete cutters I use call drilling holes into concrete core drilling...I’m happy with the terminology

Thats the common terminology,the contractors around here even have it written on their vans.

"concrete core drilling and cutting"

[goingbush]

I do not need to go right through both walls. I only have to get through the brick to the wall cavity for electrical wiring.

I priced hiring one about six weeks ago. Don't remember how much, but it was more than the $150 I can buy a drill and bit off ebay.

So my question to you is this. Did you have any issues with it jamming and risking hurting your wrists when using in an ordinary drill?

If not, I will go down the path of an SDS adapter and just a bit.

I was using an Ozito SDS rotary hammer from Bunnings, no clutch, correct you don't want it to catch & jam , the torque will spin you around, best brace yourself and expect it. If you use a chuck & adaptor it will just slip rather than break your wrist. The work kit was a Makita that looked the same as Ozito but it had a clutch & was forever disengaging.

[Bigbjorn]

Please use correct terminology, chaps. I wondered what you were on about drilling brick and masonry with a core drill. A core drill is used by a Machinist in a drill press, radial drill, milling machine, magnetic drill press to enlarge an existing hole to required size. Commonly a hole left in a casting by use of a core hence the name core drill. What you are using are annular cutters, rotary broaches, hole saws.

These are core drills.

Core Drills (https://www.msdiscounttool.com/catalog/index.php?cPath=155)

[W&KO]

These are core drills.

Core Drills (https://www.msdiscounttool.com/catalog/index.php?cPath=155)

So are these

Concrete Drilling Equipment | Smart Diamond Tools (https://smarttools.com.au/agp-concrete-drilling-equipment/)

[scarry]

As are these,although they don't seem to have a 50mm[bigsad]

We generally use the 80mm

RICD40LD 40MM SDS Core Drill Light Weight | Drill Bits - TradeTools | Huge Range, Great Service (https://www.tradetools.com/product-range/power-tools/accessories/drill-bits/40mm-sds-core-drill-light-weight-ricd40ld)

[Old Farang]

Arh, they are all kids toys that you are using! Here is a "proper coring bit":[bigsmile]


pdc core bits are made with polycrystalline diamond compact cutters on matrix (http://www.diamond-bit.com/diamond_core_bits/pdc_core_bits.html)

152985

[V8Ian]

I'll see your little bits, OF and raise you a mole. [biggrin]

152986

[Old Farang]

I'll see your little bits, OF and raise you a mole. [biggrin]

152986
Ah, but with mine you can sit in the air con on the surface, and just pull it up when you have gone far enough! [bigsmile]

[4bee]

I'll see your little bits, OF and raise you a mole


Looks large enough to get a 16mm pipe through 58i. Not to mention a Railway Coach.[smilebigeye]

[scarry]

I'll see your little bits, OF and raise you a mole. [biggrin]

152986

That looks like the one they used to build the Cem7 tunnel.[bighmmm]

[Old Farang]

So are these

Concrete Drilling Equipment | Smart Diamond Tools (https://smarttools.com.au/agp-concrete-drilling-equipment/)
On a serious note, please do NOT use one of those back handled drills for anything other than soft wood. Half a turn when, not IF, they jam and you will have a broken wrist.

[Saulman1010]

I core drill regularly into concrete up to 150mm dia.
For glass glass pool fencing spigots and aluminium posts etc.
Cut with water. Drill plumb but wiggle the drill a bit every now and then so the bit or divot will come out of drill easily.
Reo no problem, feels like a rumble but keep speed up and lots of water.
Tip: once the divot is loose in hole, use bbq tongs to get it out!

MJS

https://uploads.tapatalk-cdn.com/20190727/d0c61575d6c41ba4a47a7f4b6030b83d.jpg

[Saulman1010]

Forgot to say: as per centering the drill, we use a timber template with a hole the same size as core drill bit just to get it started.
I think crowds like BE Hire, hire both bits and drills.

MJS

[V8Ian]

On a serious note, please do NOT use one of those back handled drills for anything other than soft wood. Half a turn when, not IF, they jam and you will have a broken wrist.
We had one of those, when I was an apprentice. We made up a short length of pipe with a chain welded to it. The chain had a hook that we would anchor to somewhere convenient and pass the pipe through the handle.