Help need adivse on core cutter

[Jel]

I probably speak for most electricians when i say i hate cutting out a core hole into an exterior brick wall.
Could someone please advise me on a 4" core diamond cutter that will be the most effective for this job? I currently have one i paid £40 from and it is total rubbish!
I have been told i need to spend at least £150 on something that should glide through?
Any advise, or tips and tricks?

 

[Amp David]

Depends on what material you are going through. The one i use is from screwfix, their own brand and sails through common house bricks and sandstone

 

[Knobhead]

Last time I used one I hired it. thank god I did, going through blue brick followed by grit stone did it no good at all.

 

[Octopus]

For a "one off" I would hire one with the special drill, if its for business use then think about the usage etc, and beware the typr of drill you have may not be suitable.

 

[Electricalserv]

Why not hire someone in your area to do the hole cutting. Alot of firms in my area won't do it. They hire a man called "bob the hole" he's there for 10 minutes maximum and thats including putting tools away etc....

 

[Geordie Spark]

Back in the 1970's, diamond drilling & cutting was a specialised thing & was always done wet. I used to work for one of the companies that specialised in this & my job was to make the core cutters, extension shafts & the drill rigs to drive them. The biggest core cuter I made was 3 feet diameter & was used to drill holes in the runways at Heathrow airport. I also made a circular saw blade 4 feet in diameter for the London Underground Jubilee Line which was under construction at that time.

Times have changed and so has the way the diamonds are stuck onto the end of the bit - so much so that we are now able to use them dry - without the brazing melting & the tips falling off.

Back on topic: I've always used Norton cores driven by a Makita machine and can tell you that the most wear to a core cutter occurs when you're drilling soft materials such as sandstone.

I once cored a 5" hole through a 24" thick sandstone wall from inside out - only to find that it ran into a cast iron reinforcing plate which was bolted on the outside of the wall !! (I was working 3 floors up & could only "guestimate" the position of this plate from looking up at it from the ground & guessed wrong) so I had to drill it all over again a bit further along. The core bit was almost a total loss after that job.

Like everything else, there are cheap core cutters & not-so-cheap & you get what you pay for.

 

[robsparx]

I have a 4 inch cutter which cost me about £50 and it has been perfectly fine for domestic brick and breeze block. Not worth spending £150 on one just to use in these situations imo

I did used to hire them, but when I had a month when I needed it 3 or 4 times I thought I may as well just buy one

 

[Dunc]

Bought a Makita core set for just under 100 sheets that's perfectly good and has done many holes (the last one took all of 10mins through block and brick!). That kit had 5 diamond core cutters (biggest being 5inch), pilot, pilot removal tool, extension bar, SDS and HSS arbours. Drive it using a Bosch 4kg SDS drill which is a little clutch happy but if you hold the drill level and steady it's an absolute breeze!

 

[morph]

is the pilot drill bit also the guide rod now? as i was looking at a new set and it never had a guide rod ??

 

[Geordie Spark]

is the pilot drill bit also the guide rod now? as i was looking at a new set and it never had a guide rod ??

No.

Generally, you have EITHER a guide rod OR a pilot drill.

Both have a taper at the end which locks ino a tapered hole in the end of the machine's spindle.

Whichever you use, you only need to use it until the core cutter is about half an inch into the wall - then you take the guide rod / pilot drill out & continue to core the hole without it, so if you use the guide rod, there's no need to drill a pilot hole for it much deeper than a couple of inches.

 

[Jel]

So what type of drill should i be using with it.
I have a 4" hole cutter from screwfix and it always seems to be such a nightmare going through brick.
I normally just use a mains dewalt sds drill?

 

[Jel]

what you think of this?
Makita 8406 110V Diamond Core Drill Set *SPECIAL OFFER* - Power Tools, Drills - Corded, Diamond


or
Makita P-74712 10pc Diamond Core Kit In Case P-74712 from Tool Chest Direct

 

[Spudnik]

You need a decent SDS 4Kg drill, which has some power behind it.

You will eventually destroy your drill if you keep using it.

The makita 8406 is perfect.

Any higher powered and the clutch wont kick in as quick and will have you spinning off the ladder.

 

[Geordie Spark]

what you think of this?
Makita 8406 110V Diamond Core Drill Set *SPECIAL OFFER* - Power Tools, Drills - Corded, Diamond


or
Makita P-74712 10pc Diamond Core Kit In Case P-74712 from Tool Chest Direct

That's the machine I use!

Plenty of torque and speed.

 

[Geordie Spark]

So what type of drill should i be using with it.
I have a 4" hole cutter from screwfix and it always seems to be such a nightmare going through brick.
I normally just use a mains dewalt sds drill?

I think it's a mistake to use an SDS for coring anything bigger than 50mm.

It's all about using the right tool for the job. i.e. I wouldn't use my Makita core drill to do the job of my Makita SDS.

I haven't always owned a core drill & used to hire one for half a day whenever I had to core a hole - I thought that was a better option than risking wrecking my SDS.