Coring a soil pipe....stuck!

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So,
Using my Makita HR2230 with a brand new Erbauer 117mm core bit to go through a double skin brick wall, no cavity (house built in 1901).
The wall is about 280mm thick and I’m about 230mm in, but I’m now getting nowhere. I keep stopping the drill and drawing a pencil line at the back of the core bit so I can see how much progress I’m making, but it’s pretty much ground to a halt and I’m not sure why.
Is the drill not Powerful enough? (710w), is the core bit not good enough even though it’s never been used? Have I hit an engineering brick that simply won’t budge?
It’s taken me approx 1 hour of pure drilling (in between breaks) to get this far.
Any ideas what I can do to see me to the end?

cheers
 
how deep is the can of the core drill?

Try to chisel out the drilled plug (it will probably break off at the joint between inner and outer course)

Is it TCT or diamond? Teeth still sharp? Bricks not damp? You're not using hammer?

The drill looks rather small to me.
 
As John asks, have you withdrawn the drill and broken away the core still sitting in the wall? Have you ckeared any debris which may be trspped inside the core drill.bit itself? Failing that, any chance of a photo?

In terms of the drill (Makita HR2230 SDS drill), 710watts is a bit gutless for core drilling (proper dry diamond core drilling mschines are generally 1200 to 1500 watts these days), and runs too fast (a core drill bit that size requires 250 to 500rpm, no more) but of more concern is that you are running a 150mm core drill bit on a completely unsuitable drill. SDS drills are6nt designed to drive large core bits and haven't got a clutch capable of fully protecting you in the event of a "catch". Because of this most of them have a limit of 50 to 80mm diameter on core drilling advised by the manufacturer. If you are unlucky and it does catch then you might end up with a twisted wrist, a sprained wrist or in extreme instances a broken wrist.
 
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Chisel out what you can, chain drill round the hole with a long thin bit, gently "wobble" the core drill so it's only cutting one part of the hole at a time. Drill from other side. Might be a bit of wall tie or a hard pebble in the brick.
Your drill is not a core drill so gearing won't be right.
 
you can do links by deducting the prefix and putting, e.g.

screwfix.com/p/erbauer-diamond-core-drill-kit-8-pcs/96229

paste that into your browser
 
Thanks guys.
So, the clutch does save my wrist as it engages quite a lot if I go off-centre.
There are no big chunks of debris in the way. When I pull the core bit out there is minimum amount of dust inside the bit, that’s mainly because it doesn’t seem to be biting into the brick.
I did notice that the drill does slow down a bit.
Can’t really go in from the outside as its too high up and I don’t have decent, secure ladder access.
It’s pretty much a one off job so buying a new/more suitable drill isn’t a cost effective solution really .
It’s the only corded tool I still use. I had to core out for the shower waste a little further along the wall and that took about 40 mins.
I’ll take some pics tomorrow.
 
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So, having done a bit of research, the DeWalt D21570k gets good reviews and is half price at one place.
It’s non-SDS though, so would I have to rebut my core bits?
 
B*ll* ! :( Looks like I’ll have to persevere then.
Oh and the half price DeWalt I saw on a website.....old page they hadn’t taken down. Dirty trick to get you to register with them.
 
Stitch drilling a circle of small holes on the circumference of the required 117mm hole would help to reduce the amount of material the core bit has to cut through. It might identify if there was something that a drill cannot cut into.
 
After stitch drilling, if the core bit still doesn't progress, hammer the last bit out.
It should break clean enough for a collar to hide the stitching.
IMO it's the core bit that it's not up to the job.
With hilti core bit and a makita sds 2470 i went through 9 inch wall in less than 10 minutes and the clutch only engaged once.
It's important to work at low speed, however tempting it might be.
 
Can’t really go in from the outside as its too high up and I don’t have decent, secure ladder access.
It’s pretty much a one off job so buying a new/more suitable drill isn’t a cost effective solution really.
How will you finish the job then?
Hire a drill.
 
You cannot use SDS bits with a none-SDS drill - besides, they will not fit.
Generally dry diamonf core kitd consist of the core drills, an adaptor (SDS, hex and/or sometimes SDS Max), a pilot drill and a taper extractor/drift key (for the pilot bit) and an extension bar. The Erbauer sets on SFX include these so a hex adaptor should be avsilable as an accessorybeither from SFX or elsewhere. All the OP needs to do is swap the adaptir on the core drill bit

The OP stated that he intends going through from one side. Doing that always risks blowing out the face of the masonry on the exit side. To svoid this I've always drilled through until.the pilot drill comes through the face of the masonry on the exit side then finished off the drilling from.the outside to.get s nest hole. I understsnd that access can be difficult, though
 
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