Diamond core drill bit with SDS drill bouncing off the brick work

[Sprogginz]

I will continue showing my naivety here!

I wanted to drill a 127mm hole in the wall for a kitchen extractor.

I bought an Erbauer Diamond Core Drill Bit 127mm to use with my Energer 850W Rotary hammer drill (ENB465DRH) along with 250mm arbor & pilot bit.

The problem is after drilling the pilot hole and starting to drill the hole, I can't get it to bite the brick. It's bouncing all over the place and making a mess.

Is it because the arbor is too long to start with and can't get stability so I should start with a 110mm arbor instead?

Is the drill not powerful enough and so not spinning fast enough?

I know these items are not the best quality but regardless, this shouldn't be happening should it?

I don't have it on any hammer action and it does have a clutch mechanism.
Am I supposed to push hard against the wall, unfortunately I have to stand on a ladder to do this so not the best position for leverage.

I did try putting this job in MyBuilder just to drill the hole but got no replies apart from one handyman who was going to chisel it out instead.

Thanks and hope you can help.

 

[blup]

A core drill should be used with hammer action off.

Blup

 

[Sprogginz]

A core drill should be used with hammer action off.

Blup

Thank you but as stated in my post "I don't have it on any hammer action..."

 

[Notch7]

A big core drill up a ladder is not a good combination.

You would be better working off a tower that is tied in some way to the house wall.

If you have hard brick it may require a fair bit of pressure.

What you can do is lean the drill a bit so the cutters are cutting into the brick one side only. When you get a few mms in, lean the drill the other way -work at it in 4 segments.

Once youve got a circular groove the core drill will have formed its own guide.

If youve made the pilot hole too sloppy that will give you problems until the core drill is in a bit

 

[footprints]

Not sure what the problem is I assume you are using a pilot drill right through then a short drill or guide in the centre of the core to hold it steady for starting, usually you can dispense with the guide after getting a start in the wall as long as you keep an eye on the angle of the drill.

 

[footprints]

I hope the ladder is a pair of steps inside and not 15ft up outside!
You will need to push so setting the steps up so you are not pushing sideways off the ladder is essential.

 

[foxhole]

I never use a pilot hole with core drill , core drill is too big to follow a core drill hole , you need to get it straight from the start.

 

[Sprogginz]

Thanks for your replies.

I'm not that far off the ground but a more secure platform would be nicer!
I can reach the hole from the floor but obviously I wouldn't have my weight behind it.

I'm starting to believe it's because the arbor is too long and the fact that I'm on step-ladders. I feel if the arbor was short where the actual drill bit was close to the drill itself then it would be more stable and could hold it so. I'm not sure if it's supposed to be that way and the one I have is only supposed to be used once you've gone through the first brick. This is it.

After all the bouncing around it did, I'm sure the pilot hole is a bit bigger than before now so that's not going to help!

Nevertheless, I have a guy coming round today to do some other work and hopefully he will be able to do it instead. I think he will just make lots of holes in a cirlce though.

 

[JimCrow]

A core drill should be used with hammer action off.

Blup

Not them all,

 

[blup]

That looks like it's intended for a percussion drill, wouldn't like to use it on an sds hammer drill

Blup

 

[Deleted member 174758]

You can still get TCT core drills which are intended to be used on an SDS - AFAIK they originated back in the days of the original massive, heavy Kango rotary drill/breakers (the pre-Milwaukee ones that you needed muscles like Garth to even lift, let alone use). Of course if you forget yourself and drill all the way through, rather than drilling from both sides, the blow-out as they exit the hole is awesome (and awful, for that matter)

 

[catlad]

If you are really struggling then you can make yourself a template out of plywood and fix it to the wall where you want your hole.

 

[^woody^]

Does the core bit have the steel central spigot that goes into the pilot hole first? If so I can't see how you can have a probelm with it bouncing.

If not, you need to get the drill up to full speed and then holding it firm, touch the wall with the core and it will make its initial groove. Do this a few times untill the groove is a bit deeper than then the bit will stay in that groove.

 

[opps]

I never use a pilot hole with core drill , core drill is too big to follow a core drill hole , you need to get it straight from the start.

?

Not sure that you mean. I always drill a hole for the pin to follow. If I drill the pilot hole at an angle the core has no option but to follow the path taken by the central arbour rod.

 

[foxhole]

?

Not sure that you mean. I always drill a hole for the pin to follow. If I drill the pilot hole at an angle the core has no option but to follow the path taken by the central arbour rod.