core drill idea

[dim_bulb]

I have a makita HR2470 an sds drill and want to know if i can use it for core drilling applications 4" core holes for extractor fans etc

whats the difference between a standard hammer drill and a diamond core hole drill?

at the moment i rent one for the day £25.00

cheers luke

 

[Penance]

I use my dewalt sds for core holes of that size and no problems yet.
Saying that, I believe the gearing of a dedicated core drill is made specifically for that purpose and so provides longer tool life.

 

[ratboymark]

ive seen two plumbers burn there makita sds drills out using them for 4 inch holes and once a customer tryed to use his bosch sds drill to put the hole in for a extractor fan and it buned out before it got to the cavity, yet i just use my makita sds drill i also havent had any problems yet

 

[alanl]

Agree with the above, I have an 18v Dewalt SDS, use it on drill only, and have no problem using a £50 102mm (107?) core drill. It usually takes 2 batteries to complete, but you need to take it steady, and slowly if possible. Dont use hammer action when using a core drill.
The cheap core bits from Toolstation are good, £50ish for a bit/arbour/extension.

Alan.

 

[nikmet]

a drill with a good quality slip clutch is important when drilling 4" holes to avoid a nasty injury, especially if your above ground level!!

 

[edrobbo8]

I know of a builder who burnt out his Makita 18v LiIon SDS Drill when drilling 102mm core drill for an extractor, didn't help that he was on hammer and full throttle......

 

[hasel5]

Use a Bosch multi drill still going strong after 4 years and 3 117mm diamond blades also chase every thing in with it

 

[topquark]

Most folk that burn them out make the mistake of using them with too high RPM ! Slower is better.

 

[pennywise]

Nice big red core drill for me:63:, I would just buy the core drill £25 a day adds up, the makita is 12 holes worth, better than destroying an SDS.

 

[dim_bulb]

very good replies thanks guys.

I think a worthwhile investment

 

[keniff]

Better torque at a slower speed mate with the core drills, and don't use a cordless sds as the others have said, also don't snap those wrists of yours lol

 

[rwb]

The fellow I work with occasionally thought it would be a good idea to use a Dewalt sds drill to cut a 4" hole, whilst working up a ladder until the drill bit and throw him off the ladder and breaking his wrist. Its all to easy to think it will be ok just this once, dont do it think safety every time. Loss of earning due to time off and loss of custumers due to not even being able to drive

 

[brucelee]

we used to drill a small centre hole with long drill bit then draw a circle round the circumference of the ducting using it as a template then proceed to drill lots of small holes around the circumference in the inside of house and as the inside was mostly thermal block knock it out with hammer and chisel was easy to smooth any rough edges inside wouldnt be possible with internal brick easier to get a core drill lol
then go outside and knock the two bricks out which was perfect for the ducting in the kitchen . thebrickie tidied it up around the ducting and we fitted a grill lol this was on hundreds of new build and very quick our boss didnt invest in core drills and sds wasnt about then lol just 750Watt to 1050Watt hammer drills which burned out after a while through drilling hundreds and hundreds of joists

on a more realistic note these days better do invest in the right tool and get a core drill
as i seen the long bit bend on my mate spin round and almost break his wrist before smacking him on the brow of his eye and blacking it instantly all the wires used to just wrap up round the drill or the auger would get stuck with no reverse facility would have to do it by hand when it did this you would have to let go or risk breaking your wrist

They made all the money and we took all the risks as for H&S ,PPE etc it was a helmet and pair of boots and the helmet was nly used sparingly such as when the NHBC guy was about but this was when dinosaurs ruled and it was more dangerous just to earn a peanut wage

 

[MarkieSparkie]

As others have hinted, the SDS tool holder is very inefficient when used in the hammer stop mode, a large core drill will quickly stress and wear the tool holder and ultimately destroy an SDS if it does not have thermal protection. If you suspect your drill of getting excessively hot, stop drilling, remove the core, switch to the max speed range and run it flat out for least 5 minutes in free air to allow the motor fan to cool the windings.
Search on here for the following threads for more useful info:
Which diamond core cutter set do you use?
Help need adivse on core cutter (Note- spelling as in thread title)

 

[nickblake]

The biggest problem is like has been mentioned if it binds you break your wrist i have used JCB core bits ,how ever i have just bought a 6kg Titan SDS drill from screwfix which can be used for chasing as well as drilling and if it binds the clutch kicks in fantastic piece of kit for £69.00 will 2 core bits and loads of drill bits and chasing bits too