I would drill a pilot hole straight through for the centering bit, scour a ring on both sides with the core plus centering bit, and make some deep holes on the scoured rings from both sides. From there you don’t even need the centering bit anymore. You can also avoid blowout by stopping early and coming from the other side.
It sounds like you had the hammer mode turned on. I'm not 100% certain, and admittedly this is unintuitive, but i'm pretty sure the optimal drilling setting for coring is with the hammer mode off (i.e. drill only). My understanding is that the hammering rapidly dulls and/or breaks off the hard cutting elements of a core bit (carbide, diamond, etc), and that unlike with a solid bit, the hammering action isn't necessary. Maybe worth investigating?
Hi, this is a carbide bit, that needs to be hammered, although it is more for brick and limestone etc., then hard cocncret. It is definitely not for reinforced concrete, fir that you need diamond bit core, that, as you mentioned,. mustn't be hammered. Also the 8mm drill is need to be removed once you reached like 2-3mm, as it serves only for centering the core bit, and will slow you down considerebly
Most welcome! Been working with these bits as an electrician. I like both types. The carbides are much cheaper and great with hammer drills,.the diamond bits.are working best with at least 1000watt(corded) drills.
As can be seen when starting in the stone, the centre guide drill was struggling right from the start. So once the hole saw section hit the stone, the drill was trying to drive both the hole saw and the guide drill. Maybe drilling a smaller pilot hole first would at least reduce the workload on the guide drill.
Just bought an "82mm" diamond core drill and adaptors for normal and sds plus chucks. Would be interesting to see the same drill drill the same rock and use the old footage for a side by side overlay. Trouble with my new bit is it's 80-80.5mm and I'm not confident it'll bore oversize by 1.5-2mm to get my 82mm PVC through. Hmmmm.
Hmmm oversizing with core bit? that I can't tell you, but if you drill almost through and then perforate with say a 10mm bit all around the hole it might be big enough.
@@BoltahDownunder My intention is to pre drill all the way through with a plain impact pilot, then get the big hole started straight and steady, then stop, measure, and if good continue, if not remove the drill from the centre and work it around in circles at all depths as I go further in so as to enlarge it as I go effectively using it like a drum sander or something. I'll let you know how it works out and when I go to pick up the adaptor I'll measure some of the other sizes and see how they compare with the number on the box/laser engraving.
Hi I like your hole punch channel and I think you have a spot on, I use makita batteries but I don't know if the dhr 243 is reliable and strong enough. Harseam bosch gbh 18v -26 or Ryobi or this DeWalt. What is your recommendation.
What's your application? Makita should be reliable enough for most uses. But the 243 doesn't hit that hard. You could upgrade to a DHR 282 if you want more impact energy. Or if you want to change brands I can recommend the DeWalt DCH263. It's also 28mm rated and hits hard but is quite affordable & nice to use
@@BoltahDownunder remember those kind of holds, but I was more thinking about those awfull chipped holds: ua-cam.com/video/4RNDkyjeU9E/v-deo.html (look behind the guy)
That centering bit should be removed once you have your core established
I would drill a pilot hole straight through for the centering bit, scour a ring on both sides with the core plus centering bit, and make some deep holes on the scoured rings from both sides. From there you don’t even need the centering bit anymore. You can also avoid blowout by stopping early and coming from the other side.
for sure! i worked that out eventually
It sounds like you had the hammer mode turned on. I'm not 100% certain, and admittedly this is unintuitive, but i'm pretty sure the optimal drilling setting for coring is with the hammer mode off (i.e. drill only). My understanding is that the hammering rapidly dulls and/or breaks off the hard cutting elements of a core bit (carbide, diamond, etc), and that unlike with a solid bit, the hammering action isn't necessary. Maybe worth investigating?
Hi, this is a carbide bit, that needs to be hammered, although it is more for brick and limestone etc., then hard cocncret. It is definitely not for reinforced concrete, fir that you need diamond bit core, that, as you mentioned,. mustn't be hammered. Also the 8mm drill is need to be removed once you reached like 2-3mm, as it serves only for centering the core bit, and will slow you down considerebly
@@tamaskep4902 ah - turn the hammer off on diamond only, eh? good info - thx!. Good point on the guide bit too
Most welcome! Been working with these bits as an electrician. I like both types. The carbides are much cheaper and great with hammer drills,.the diamond bits.are working best with at least 1000watt(corded) drills.
@tamaskep4902 Thanks mate! That makes sense that the pilot bit can be taken out. It didn't help much.
@@BoltahDownunder my pleasure. Your tests helped me to choose a great hammer drill( a HIkoki 36v), so thanks 🙏
As can be seen when starting in the stone, the centre guide drill was struggling right from the start. So once the hole saw section hit the stone, the drill was trying to drive both the hole saw and the guide drill. Maybe drilling a smaller pilot hole first would at least reduce the workload on the guide drill.
Hand digging a tunnel through a lava flow using these..
Just bought an "82mm" diamond core drill and adaptors for normal and sds plus chucks. Would be interesting to see the same drill drill the same rock and use the old footage for a side by side overlay. Trouble with my new bit is it's 80-80.5mm and I'm not confident it'll bore oversize by 1.5-2mm to get my 82mm PVC through. Hmmmm.
Hmmm oversizing with core bit? that I can't tell you, but if you drill almost through and then perforate with say a 10mm bit all around the hole it might be big enough.
@@BoltahDownunder My intention is to pre drill all the way through with a plain impact pilot, then get the big hole started straight and steady, then stop, measure, and if good continue, if not remove the drill from the centre and work it around in circles at all depths as I go further in so as to enlarge it as I go effectively using it like a drum sander or something. I'll let you know how it works out and when I go to pick up the adaptor I'll measure some of the other sizes and see how they compare with the number on the box/laser engraving.
Hi I like your hole punch channel and I think you have a spot on, I use makita batteries but I don't know if the dhr 243 is reliable and strong enough. Harseam bosch gbh 18v -26 or Ryobi or this DeWalt. What is your recommendation.
Used a Bosch and dewalt side by side and this dewalt wipes the floor with the Bosch
What's your application? Makita should be reliable enough for most uses. But the 243 doesn't hit that hard. You could upgrade to a DHR 282 if you want more impact energy.
Or if you want to change brands I can recommend the DeWalt DCH263. It's also 28mm rated and hits hard but is quite affordable & nice to use
Take the center bit out after the core is started
seem to be perfect to manufacture holds on route! (well this is off course a joke :p )
Lol. Back in the 90s there was a style of inset gym holds that fit into a big hole like this, so you're not wrong!
@@BoltahDownunder remember those kind of holds, but I was more thinking about those awfull chipped holds: ua-cam.com/video/4RNDkyjeU9E/v-deo.html (look behind the guy)