4" core bit, cuts just like butter, yeh right!

[Top Cat]

Fitting an inline fan today. Brought my 4" core bit in and the guy says "oh those are great, it cuts through brick like a knife through butter". Yeh right i thought.

Started to cut hole, the bricks were hard as rock! Also it was an old place so no cavity so you had to go through 2 lots of brick so the drill kept binding.

3 hours it took me! You could fry an egg on my drill it had got so hot!

If i had had any strength left in my arms i would have shoved the guys head through the hole i had just made!

Anyone know the best core bit to buy?

 

[GLENNSPARK]

well i know my knife cuts through lurpac just like butter....lovely on your crumpets that is.....sayin that.....saw this lass earlier on...thought a bit of lurpac would look lovely on her crumpets n all.....

 

[Darkwood]

Been there done that and got the twisted wrist :O/ .... some jobs it does goe through simples but some as you've found can be a pain, if you have got the engineering bricks, start the drill outide get your 4"" cut mark then end a pilot drill 12mm through 8 times around the circle (straight if you can) then use core drill, it'll knock couple hour off easily.

 

[Top Cat]

Been there done that and got the twisted wrist :O/ .... some jobs it does goe through simples but some as you've found can be a pain, if you have got the engineering bricks, start the drill outide get your 4"" cut mark then end a pilot drill 12mm through 8 times around the circle (straight if you can) then use core drill, it'll knock couple hour off easily.

Good idea!

 

[telectrix]

good tip. my tip is to make the builder cut the hole.

 

[PC Electrics]

A builder once told me that if they bind it's due to dust build up around the core bit. You should remove it from the hole to clear dust regularly.

I've also found it's vital to keep the core straight and square as you go through the hole.

And remove the centre drill once you're about 5mm in!! It'll hold you back if you leave it in.

You'll ruin the core bit if it gets too hot. Each time I remove it for dust clearing I let it run for 30 seconds or so in free air to cool the drill and bit.

9 inch brick wall should be about 30 mins, but it has taken up to an hour when the bricks have been hard.

I use Norton bits.

 

[geordie]

what sort of drill were you using. I used to use a SDS but got a core drill and never looked back

 

[GLENNSPARK]

Been there done that and got the twisted wrist :O/ .... some jobs it does goe through simples but some as you've found can be a pain, if you have got the engineering bricks, start the drill outide get your 4"" cut mark then end a pilot drill 12mm through 8 times around the circle (straight if you can) then use core drill, it'll knock couple hour off easily.

now you need to watch it a bit doing this.....agreed it will cut time down but it could also ragg the carbide teeth out of the coredrill n all......constant steady cutting is the order of the day with such tools....not intermittent cutting....the edges often can`t cope with it.....

 

[cakey]

As said above remove core bit from hole often to prevent dust build up. Also always use a proper core drill as the torque and speed are different from normal drills which not only take a lot longer to drill with but will burn out pretty sharpish too. Obviously dont use the hammer setting and let the drill do the work!! Your wrists will appreciate a good strong grip with both hands too.

 

[GLENNSPARK]

the trick is n all is not to go too lightly with it.....steady pressure...keep it working...keep it cutting....otherwise its just rubbing and not doing any real work.....overheat that will.....its like when using millers and lathes.....tooling needs to be working....or it just overheats.....

 

[GLENNSPARK]

to kill a drill.....

 

[Darkwood]

the trick is n all is not to go too lightly with it.....steady pressure...keep it working...keep it cutting....otherwise its just rubbing and not doing any real work.....overheat that will.....its like when using millers and lathes.....tooling needs to be working....or it just overheats.....

did you used to be a JEDI!!!!!

 

[bwm730]

Get yourself a decent core drill, i bought a Bosch GSB 162-2RE and recently cut 4 x 5" and 1 x 4" cores in a morning. It also has a good safety clutch to save the wrists

 

[GLENNSPARK]

Get yourself a decent core drill, i bought a Bosch GSB 162-2RE and recently cut 4 x 5" and 1 x 4" cores in a morning. It also has a good safety clutch to save the wrists

go for the hilti.....or Dr bender...best you`l get them......marcrist are good n all....

 

[sedgy34]

Good idea!

HEY T,C

thats the only idea think we all have the t shirt ( hope yours fits) lol