- Thread starter Onoff
- Start date
Pete.
Member
- Messages
- 14,587
- Location
- Kent, UK
A stuck SDS bit is one of the hardest things to remove. As Brightspark said you can't enlarge the holes unless you go much bigger - we do it all the time by drilling a 16mm hole followed by a 32mm hole and that works fine, but you can't for instance follow a 16 with an 18 or 20 it'll get you jammed nearly every time.
You can't (usually) wind them back either because the shank is spiral for clearing the dust but the end is round for keeping the hole round. Going backwards will auger the dust down the hole and pack it tight behind the drill end. Turning back and forth slightly is more likely to work but unlikely in your case.
Your easiest way out is to cut off the bit at floor level and diamond drill the hole over the top with a long 65mm bit. I know you don't have that kit so your next best option is to very carefully start a new hole with a new sds bit slightly away from the stuck bit but drilling towards it at a very shallow angle. You have to judge the depth you're at with the stuck bit and try to angle it so your new hole meet the end of the stuck drill. Go carefully so that it doesn't also get stuck (I've seen someone get three jammed together)and be ready for when the new hole breaks into the old one and stop drilling immediately If you get it right the new hole will release the stuck bit - if not you'll have both drills stuck. Again it's not east to do (in fact from your pic I'd say it's very difficult I'd give it about a 20% chance if I was doing it.
You can't (usually) wind them back either because the shank is spiral for clearing the dust but the end is round for keeping the hole round. Going backwards will auger the dust down the hole and pack it tight behind the drill end. Turning back and forth slightly is more likely to work but unlikely in your case.
Your easiest way out is to cut off the bit at floor level and diamond drill the hole over the top with a long 65mm bit. I know you don't have that kit so your next best option is to very carefully start a new hole with a new sds bit slightly away from the stuck bit but drilling towards it at a very shallow angle. You have to judge the depth you're at with the stuck bit and try to angle it so your new hole meet the end of the stuck drill. Go carefully so that it doesn't also get stuck (I've seen someone get three jammed together)and be ready for when the new hole breaks into the old one and stop drilling immediately If you get it right the new hole will release the stuck bit - if not you'll have both drills stuck. Again it's not east to do (in fact from your pic I'd say it's very difficult I'd give it about a 20% chance if I was doing it.
Munkul
Jack of some trades, Master of none
- Messages
- 7,660
- Location
- Cumbria
long SDS chisel and break the surrounding concrete out?
If the slide hammer and stilson doesn't do the trick, then maybe you're missing a consumable... it's called percy..
...Percy-verance, we teach our apprentices to bring some along on most jobs
If the slide hammer and stilson doesn't do the trick, then maybe you're missing a consumable... it's called percy..
...Percy-verance, we teach our apprentices to bring some along on most jobs
Onoff
In the land of the unfinished project I am King!
- Messages
- 12,145
- Location
- Sevenoaks, UK
Live and learn. Bought the 1m bits years ago but not used them. I've never, either, drilled through solid concrete at this depth.
Pretty sure I've used masonry bits before going up in small size jumps but that was likely only through lightweight block walls.
A hard lesson to learn this one as that is the only place I want my cables coming in!
Pretty sure I've used masonry bits before going up in small size jumps but that was likely only through lightweight block walls.
A hard lesson to learn this one as that is the only place I want my cables coming in!
Westfield-builder
Member
- Messages
- 1,652
Maybe you should have put a suitable duct in during the build ??
I've definitely used a smaller diameter drill to get exact placement and then gone up in sizes, not just through soft blocks either.
I've definitely used a smaller diameter drill to get exact placement and then gone up in sizes, not just through soft blocks either.
pedrobedro
Man at Matalan
- Messages
- 13,005
- Location
- CX near Chesterfield
Weld a nut on it or a T across the end, put your grips behind it around the drill then knock it backwards with a hammer with a good shaft
Onoff
In the land of the unfinished project I am King!
- Messages
- 12,145
- Location
- Sevenoaks, UK
Garage was built long before I bought the place.
if you have a welder... then take that broken club hammer head knock the wood out and slide that down your bit... then weld some scrap over the end of the bit and use the sliding head as a slide hammer. tie some rope to it and put a gum sheild in if you want to give it some monty...
Onoff
In the land of the unfinished project I am King!
- Messages
- 12,145
- Location
- Sevenoaks, UK
I first started drilling just off the vertical but gave up and went at approx 45deg. The slurry filled hole at the bottom is the near vertical hole. The one with the stuck drill is the one I'd like to continue through at 45deg. The SDS bit looks off centre to the 65mm hole but that may be due to jammed debris. Hoping another go with a long drill might break it up a bit. I wonder if the stuck drill in fact is being held in a bit of a bend over its length. Looks like there's a big chunk of something loose just North of the drill bit:
123hotchef
Member
- Messages
- 14,259
- Location
- Kent
tha
that would be my route too
Matchless
I started with nothing, still have most of it left
- Messages
- 2,739
- Location
- Essex UK
and this is why I paid £125.00 to get a guy to drill through my thick reinforced garage floor at 45deg to get my 3 phase cable in, The nearest adjustable angle bolt down drill I could rent was 30 miles away, I would have needed to buy a core drill, in reality it cost me very little compared with two 60 mile round trips and rental charges at a very busy time, don't get me wrong, I am as tight as a ducks whatsit but sometimes ............
mtt.tr
Member
- Messages
- 8,437
- Location
- Essex/Suffolk border
Onoff
In the land of the unfinished project I am King!
- Messages
- 12,145
- Location
- Sevenoaks, UK
It's putting up a fight! Stilsons won't budge it. Tried whacking the broken club hammer head up against the Chinesium adjustables using the burr as a stop. A big no on that score. I'll carry on trying to drill round the stuck bit.
zx9
Forum Supporter
- Messages
- 5,182
- Location
- South East London
Good point re the mess, and if you had a wet vacuum you would have probably used it to clean out the slurry already.
Morrisman
Member
- Messages
- 8,545
- Location
- Staffordshire, England
I've never used water when hammer drilling, as I assumed it would turn the powdered concrete back into concrete, put simply. I always keep withdrawing the drill to clear the flutes of dust and detritus, like with any drilling operation, as I can feel the drill drawing tighter and tighter the further in I go.
Of course, this excellent advice is two days too late.
Of course, this excellent advice is two days too late.
Onoff
In the land of the unfinished project I am King!
- Messages
- 12,145
- Location
- Sevenoaks, UK
I've never used water when hammer drilling, as I assumed it would turn the powdered concrete back into concrete, put simply. I always keep withdrawing the drill to clear the flutes of dust and detritus, like with any drilling operation, as I can feel the drill drawing tighter and tighter the further in I go.
Of course, this excellent advice is two days too late.
I was using the water when core cutting.
MoreWellie
Member
- Messages
- 1,820
- Location
- Bedfordshire, UK
given the amount of time you have used trying to get this out, might it be a good idea to cut it off as low as you can, fill the hole with cement and start a new hole a bit to the right?
