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I need to drill a hole in my house walls for ducting for a PIV unit.
The walls are made of old bricks (19th century) and are 550mm deep once you include the outside harling and the interior plaster.
The extractor fan has a 99mm diameter outputs.
I have a 5kg Titan SDS drill that should be able to handle it, however, I don't have any core drill bits and once I started looking at them I found them very confusing.
It seems like as well as the drill bit itself (and it seems I need a diamond one for bricks?) I think you need:
SDS chuck adaptor
An arbor?
A pilot drill
A drift key?
Extension bars(s)?
I've looked at them online at Screwfix/Toolstation etc and it seems really complicated with some of those parts not fitting other parts they sell. It also seems like the 550mm depth could be an issue - none of the bits I've seen are that long. And neither are the extension bars?
They sell sets but they don't seem to have the right diameter bits I need. I'm assuming I need a 107mm diameter bit?
Am I just better off hiring something from HSS or someone similar. Just tell them I need one for a 107mm*550mm hole using an SDS drill?
Am I just better off hiring something from HSS or someone similar. Just tell them I need one for a 107mm*550mm hole using an SDS drill?
Unless you have to drill a few holes almost certainly, decent core drill bits can be horrifically expensive.
And as you say, nice and easy to tell someone else what size hole you need and let them work it all out
Yeah, it's just a single hole really. I will put a couple into my outbuilding as well for ventilation there, but it's just a single brick thick. Was going to use that as a practice run!
I would say rent, you should be able to get a core drill from your hire place?
What is the access on both sides like? Thinking you use a 650mm SDS bit to get the pilot hole through the wall, cut from both sides to reduce blow out.
The arbour holds the pilot drill in the middle, you attach the arbour to the cutter and in use the drill bit stops it wandering off. Extension bars are screwed to the bottom of the arbour to give you more reach. You can get really long extension bars though.
https://www.ffx.co.uk/product/Get/Silverline-719797-5055058164094-Sds-Plus-Core-Drill-Arbor-600Mm
Only used a smaller core drill through single skin brick to be fair. Guessing with that depth you need to chisel out part of the core once you max out the depth.
Similar to Kimura,
The pilot bit and arbor will be used to start the hole. Look at hole saws for a smaller scale idea.
Once you have the hole started you are free to ditch the pilot bit and drill to the full depth of the core barrel. once there stop drill out and crack out the core. the core may come out with the barrel if yo pass a construction joint in the brick or block. after that the core barrel will be guided by the hole you have drilled, add on extension bars as required.
it's a simpler process to do than explain.
you're probably going in dry with that drill.
Check your drill has a decent clutch.
If the core bit snags, you'll soon find out how good it is.
As said above, probably better to hire the whole shebang, or get a local drilling company to price it as a comparison
Arbour is the part the actual hole saw screws onto and holds the pilot too. When I used one the pilot hole was drilled right through first then a plain pilot made sure the hole was centered.
Drift key is for knocking the core out of hole saw when finished drilling.
Extension bars obviously for increasing the depth of the cut. It's been a while since I used one, but I'd be surprised if you can't join multiple together to increase the depth.
Definitely hire one.
Don't forget to switch off the hammer function or you'll smash the cutting bits.
Hmm, hadn't really thought about getting a company in.... Might have a look around
This is the drill I have: https://www.screwfix.com/p/titan-ttb278sds-6-3kg-electric-sds-plus-drill-9-piece-accessory-kit-230-240v/97533#product_additional_details_container
It says it has a clutch...
I checked the website, rated capacity for that drill is 32mm masonry, instructions said it is the same for core and regular SDS bits.
Likely could do it, but I would still be tempted to hire the kit instead to be sure.
I have that drill
Its a monster , Will easily do the job . Mine pushed a 450mm x 16mm sds through a cavity brick wall withooout blinking
You might need a TCT holesaw and extension rods and hammer and cold chisel if your core wont come out cleanly
Not from experience obviously but don't use them on hammer even by accident for a few seconds at the outset because the guide bit won't come back out...
550mm depth, a whole 22" 😯
Expect severe arm pump, right up to and including the shoulders. So remember to take a break and not stand there holding it too long and shake some of it out your arms.
I've done a couple of cores, mainly due to a single job but I remember it hurt like hell and probably made worse by the fact we'd only a platform which meant i was holding it pretty much shoulder height.
Prepare yourself for the fact it's going to take some time. Possibly a couple of hours or more to get through.
Also, the wall is unlikely to be actually solid, possibly just made of an outer and inner skin with the middle filled with rubble so shouldn't be too much issue with cores getting stuck.
I've done a couple of extractor holes along with drain pipe holes using an aldi drill similar to your titan and using eBay core drills. Regular breaks a must - just do it bit by bit. You're going to hurt at the end!
It’s going to be dusty too! Filter mask and specs or goggles would be handy. Hire the kit probably surprisingly cheap compared to buying the bits.
Check your drill has a decent clutch.
If the core bit snags, you’ll soon find out how good it is.
I was just going to say this and want to reiterate it.
How neat does it need to look? Could you stitch drill a suitable hole using the drill bits you already have?
It’s going to be dusty too!
I may well be wrong, but i would be doing it wet.
Diamond bit should make light work as long as it has cooling and lubricant in the form of water. doing it dry will just ruin the bit wont it?
I've got a number of core drills from when I put in extension / bathroom inc soil pipes. I used a light 3kg SDS doesn't need to be massive and you'll be holding it for a while..! No clutch but wound power down took it slow, be aware which way it might kick. Used a spray bottle of water to keep cutter lubricated. Goes through breeze block in a flash but brick takes a while. Let the drill do the work you should be forcing it / leaning on it. £50-60 for a new SDS and £50-60 core drill set off eBay (there's a Silverline set inc arbor and pilot etc) is all you need, about the cost of a weekends hire.
If you watch that, he shows you how to hold the drill correctly
So, a wee update.
Although using water and following the above video, I got about 30mm in to the brick before the drill kicked the bucket. SDS chuck knackered and just clutching continually.
Have borrowed a specialist Hilti drill off my building site pal and will give it a second go at the weekend
If the core bits are designed to be used dry don’t spray water on them to cool them! The heat is expected and helps the drilling. If you spray water on them all you will do is make a paste and stop the cutter working as well.
The big water cooled units have different blades on them to work with the water which is usually used for dust suppression not cooling.
I have my own set of core bits and never had any heating issues running them through brick/stone/block up to around 800mm thick. Patience is the key!
Well Hilti drill was a no go as handle missing!
Resurrected my drill and got a bit further with it.
Unfortunately the bit jammed and the drill got away from me and dragged me in as it spun round and smacked me in the face, so sitting in a&e waiting for a couple of stitches.
It's a sair fecht this drilling malarkey!
@yourguitarhero - Eek, that counts as a lucky escape. Hope you are OK and stitches are minor.
Maybe time to get someone in with the full kit instead, if you have had a couple of goes at it?
Predictably ended predictably !
Hope they ain't too bad , fingers crossed you can still drink beer when you get home -for medicinal purposes of course.