QUOTE(eddie2020 @ Jan 20 2022, 04:00 PM)
Hi Guys,
Need some advise, I wanted to drill some mount for curtain rail, TV cabinet etc.
So I invested a cordless Bosch drill with hammer function.
On my 3rd room I drill for 1 hole used over 1hr - 2hr. It's ccrazy, then I curi Ayam by not drilling too deep for other hole (need 3 bracket, 1 full depth, another 2 I cut off nail and the plug to half).
Each time I drill, its smooth for 1.5cm around 0.6inch then it become damn hard , I think it's concrete, and 1.5cm it's cement?
I am using mansory drill bits and I try switching a few with my uncle itss still give similar result.
I also borrowed my uncle corded hammer drill, black decker hit 1.5cm then become very hard to drill like not moving..
Aircond installer come they also complaining my wall is very hard to drill which they use a lot force, they said normally few min 1 hole they did, my hse like near half n hr for 1 hole.
Need some advise as below.
1. If I just drill 1.5cm and cut plug with screw, will it dangerous? cause I not sure how much weight it can take.
2. If I shall drill full 3cm (normal screw n plug length) any tips to proceed the hard rendered concrete I assume? not sure is my drill bit problem or drill or skill.. haha
Edit =high rise condo
You will need to use a hammer drill. Please ensure you have opted for hammer drill function instead of just drilling by turning the knob to the right option. When it comes to reinforced concrete (RC) floor slab on highrise, it is casted using metal formwork, hence one will have a smooth surface on the soffit. Hence, a skim coat of between 3mm to 5mm will be applied on the slab surfaces as finishing.
Your drill bit managed to go through the hard concrete thanks to the hammering action. At 1.5cm, you may have hit steel bar. A common drill bit is only designed to drill into concrete substrate unless you opted for tungsten head drill bit, that can drill into steel.
The danger of hitting a steel bar using a common drill bit is when your drilling machine get stuck and the rotating machine may break your wrist. Ceiling drilling may also exposed you to the risk of drilling into electrical conduit. You will know it when you hit it.
For curtain installation, you will need to drill in at least a minimum of 2.5mm (assuming there is no curtain pelmet with wood base) using an M6 (6mm diameter drill bit). The depth is required as curtain can be heavy and also to resist tugging by children when they are playing around this area.