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start drilling wall Answered

I want to stand on in front of the wall and start drilling..
But before this I want to know that, how is possible to know the exact position of perforation of the other side of the wall.
And please explain completely since I'm amateur!

Wall Specification:
Somewhere in the middle of the wall metals has passed.
Wall diameter: 50cm
Wall gender: cement and stone
Acceptable amount of errors: 5cm


I want to know exact location of leaving drill point before the wall broken and start drilling with signing...

Something like laser pointer tag that can pass through the wall and not to harm the wall...

And please don't mention metal detector because its accuracy is so low!


If your laser pointer can shine through a concrete wall, you don't need a drill...

usually on this sorta thing, finding a common reference point, like a window frame is the key. Measure from the windowframe on the inside and outside. Mark it, and take care to drill straight.

sometimes a pilot hole is useful.so, if the ultimate goal is a 10 cm dia hole, start with a 1 cm bit.

As a tipp from past experience:
Let the machine do the work - don't use force to get the drill in.
If you hit metal turn off the hammer and ony drill - a good masonry drill has hardened blades in the tip - these will cut through metal if give them a chance.
When possible cool the drill bit with water when hitting metal to prevent the tips breaking.

Do not try and drill from both sides to meet in the middle.

Instead, buy a drill-bit long enough to get right through the wall.

Depending where you are shopping, look for a masonry bit that is long enough (and thick enough) for your needs (if your wall is 50cm thick, then go for a 60cm/600mm drill-bit). You will need a hammer drill to get through the wall.

To get a reasonably accurate idea of where the drill will emerge, measure the height of your entry point, and the distance along the wall from an obvious landmark, such as a doorway, then measure the same points on the other side of the wall.

You say "somewhere in the middle of the wall metals has passed" - if that means pipes or cables, you need to find them. You can get a rough idea if you know where the ends of the pipes/cables are, but you can also buy small metal detectors to check exactly where they are. If you mean structural metal, like a girder or RSJ, then you will need an HSS twist bit to penetrate it. When you get to the metal, swap the masonry bit for the twist bit, and switch off the hammer function of your drill. When you are through the metal, swap the bits back, and switch on the hammer function again.