Core drill

[Pocster]

Hey all

 

got plenty of holes to drill through reinforced concrete wall and floor.

any recommendations for the drill ?

 

cheers 

[PeterW]

one that doesn't break your wrist....

 

If you hire one, check the clutch torque has been set properly - how big are the holes you want to drill...??? Some are set to "break" with 150mm cores in them, so with a 50mm core it will try and take your arm with it as the clutch won't give with a smaller core...

 

 

[Alexphd1]

We used a 127mm standard dry core drill with a makita 8406 drill in 150mm ICF concrete. We have the same kit as this  http://www.britishbathroomcompany.co.uk/rothenberger-89020-roth-12pce-dry-diamond-core-drill-kit?gclid=Cj0KCQiAl8rQBRDrARIsAEW_To98Y6s2EJ_ndTutB7A6vVOsNbFB7PrJLB04YVPCS4kNQSL1__9Ys0QaAmFbEALw_wcB .  If you have many holes may be worth looking at a wet system unfortunately I have no experience of these.

Edited November 20, 2017 by Alexphd1

[Pocster]

Thanks 

looking at largest hole being toilet waste pipe so maybe 6” that’s the worse one through 6” reinforced concrete 

others are easier :-)

[PeterW]

So that’s a 127mm core which I would really be doing very carefully with a big hired in hole drill. Anything up to 50mm you can do with decent cores on an SDS but above that you are into wrist breaking - or being thrown off a ladder by the torque ...

[TerryE]

+1 to Peter's advice. Hiring the right tool doesn't cost that much. A lot less than dealing with a badly broken wrist.

[Alexphd1]

Just put of curiosity what drill would you guys been hiring? 

[PeterW]

Mine was a Hilti core drill with Ox cores. 110v and massive torque ..!!!

[Onoff]

I've been using eBay cheapies:

 

 

 

 

[Alexphd1]

hilti dd130?

 

[Pocster]

These Hilton hire ones do they have a stand and you bolt the thing to the wall or floor ? I.e you don’t hold so no broken wrists !!

[Nickfromwales]

Any decent core ( diamond NOT Tct ) will have a clutch that any reasonably robust man can hold onto, I've used them all. 

Where depths are greater than the depth of the bit you need to go halfway in and then break the core out before carrying on. It's the dust / debris held between the core and the bit that cause it to snag. 

With a makita or dewalt dedicated diamond core drill I'll happily drill for a boiler flue up a ladder. Ask for a drill with an electronic clutch and you'll be fine. 

50mm cores you can do in your sleep. 

[Pocster]

7 minutes ago, Nickfromwales said:

Any decent core ( diamond NOT Tct ) will have a clutch that any reasonably robust man can hold onto, I've used them all. 

Where depths are greater than the depth of the bit you need to go halfway in and then break the core out before carrying on. It's the dust / debris held between the core and the bit that cause it to snag. 

With a makita or dewalt dedicated diamond core drill I'll happily drill for a boiler flue up a ladder. Ask for a drill with an electronic clutch and you'll be fine. 

50mm cores you can do in your sleep. 

Hitting rebar is ok ?? 

 

Still rather buy one . I like new toys. Also no time pressure and can always sell on...

Edited November 21, 2017 by pocster

[Bitpipe]

28 minutes ago, Nickfromwales said:

Any decent core ( diamond NOT Tct ) will have a clutch that any reasonably robust man can hold onto, I've used them all. 

 

And so is born the 'reasonably robust man' test.

[Alexphd1]

We hit 1x 12mm rebar and it went through it fine. We then used a concrete grinding disc on a handheld grinder to square of the hole for the beam. We also cored a hole below dpm in concrete block, that was a nightmare due to block being damp?

[Pocster]

14 minutes ago, Alexphd1 said:

We hit 1x 12mm rebar and it went through it fine. We then used a concrete grinding disc on a handheld grinder to square of the hole for the beam. We also cored a hole below dpm in concrete block, that was a nightmare due to block being damp?

Cool !

 

Im man enough to break my wrist.

home drill will do !

[Nickfromwales]

1 hour ago, pocster said:

Still rather buy one . I like new toys. Also no time pressure and can always sell on...

Get £600 ready to lose ?

Hire, hire, hire. Use, abuse return.  

[PeterW]

1 hour ago, Nickfromwales said:

Get £600 ready to lose ?

Hire, hire, hire. Use, abuse return.  

 

Yep I second that ..!! Mine cost me £40 inc VAT including paying £15 for the 52mm core drill that I sheared two teeth off when it bounced off an exceptionally hard brick ..!

 

I wouldn’t buy one, as putting it bluntly I wouldn’t buy a 2nd hand one as they need proper servicing ..! I watched them test the torque on the clutch before they handed it over to me, and if I was buying 2nd hand how do I know what abuse it’s had ..?? 

[Onoff]

In my case with the TCT core cutter above if I hit steel then I have to change to a bfo Starrett cutter.

 

Going to beg/steal it borrow a diamond one if I go for a single room MVHR.

[PeterW]

There’s a difference between drilling brick and block and drilling rebar reinforced concrete ... A cheap TCT will do one or two holes in brick and block, show it concrete and you will be there for days ... 

[Onoff]

19 minutes ago, PeterW said:

There’s a difference between drilling brick and block and drilling rebar reinforced concrete ... A cheap TCT will do one or two holes in brick and block, show it concrete and you will be there for days ... 

 

You're telling this to a man who drilled thru his footings with one for the new water main!  Never thought it would end!

 

 

 

Even with the home made extension bar:

 

 

[Alexphd1]

+1 for diamond never used a TCT (had to Google it??). Only material we stayed clear of was granite (Aberdeen grey granite) we needed a bolt on water cooled drill, nice bits of kit but expensive. We have the same makita dry core drill just over ten years but have never used the hammer function think we paid about £190 probably still worth £50 on eBay! Think they are about £250 now. 

[Nickfromwales]

5 hours ago, Alexphd1 said:

We hit 1x 12mm rebar and it went through it fine. We then used a concrete grinding disc on a handheld grinder to square of the hole for the beam. We also cored a hole below dpm in concrete block, that was a nightmare due to block being damp?

Yup. I always kango them out after drilling a series of holes to reduce breakout. Damp brick / brickwork is a real pita when dry diamond core drilling . 

[curlewhouse]

I've just got to go through 150/200mm of sandstone - I'm wondering now if I'll actually get away with some eBay cheapies instead of anything more expensive.