I am going to drill 6 holes in a concrete wall to mount a wall bracket for a 40" LCD TV with a relatively long arm (large moment).
Max leverage arm about 60cm
Weight of TV about 15kg
For practical reasons, I want to drill the holes as close to the edge as possible (see image).
How close can I safely drill approximately?
Very grateful for answers.
Max leverage arm about 60cm
Weight of TV about 15kg
For practical reasons, I want to drill the holes as close to the edge as possible (see image).
How close can I safely drill approximately?
Very grateful for answers.
Many who have read but no one dared 
advise. It also depends on what "concrete wall" means, concrete hollow blocks? cast wall? light concrete? brick with plaster? etc.
Without any theoretical knowledge in concrete strength, I would choose to drill at least 300 mm from the corner. I don't guarantee it will hold, but that's where I would drill based on my practical experience.
advise. It also depends on what "concrete wall" means, concrete hollow blocks? cast wall? light concrete? brick with plaster? etc.Without any theoretical knowledge in concrete strength, I would choose to drill at least 300 mm from the corner. I don't guarantee it will hold, but that's where I would drill based on my practical experience.
Thanks for the response
I don't know much about the wall, except that it feels very solid and thick. It can be said that it's the "outer wall" of a high-rise building built in the 60s if that helps in any way.
I was hoping for maybe 50mm from the edge
I'm not necessarily asking for calculations, just a bit of common sense.
I don't know much about the wall, except that it feels very solid and thick. It can be said that it's the "outer wall" of a high-rise building built in the 60s if that helps in any way.
I was hoping for maybe 50mm from the edge
I'm not necessarily asking for calculations, just a bit of common sense.
Hello!
Try 50, buy concrete screws at beijer so you don't need to pre-drill or use plugs!
Then you just need to put up the bracket and "jiggle" and "tug" at it a bit to see if it holds!
I personally put up a 60kg punching bag in the garage with 4 concrete screws from beijer! Works great!
Experiment and see
Best regards!
Try 50, buy concrete screws at beijer so you don't need to pre-drill or use plugs!
Then you just need to put up the bracket and "jiggle" and "tug" at it a bit to see if it holds!
I personally put up a 60kg punching bag in the garage with 4 concrete screws from beijer! Works great!
Experiment and see
Best regards!
Is it possible to glean any tips by looking at these tables?
http://katalog.essve.se/webspeed/katalog/kat_produkt.p?bid=V70&kat_bid=V70&dokid=wc398835
I'm mostly thinking about the column "minimum edge distance".
http://katalog.essve.se/webspeed/katalog/kat_produkt.p?bid=V70&kat_bid=V70&dokid=wc398835
I'm mostly thinking about the column "minimum edge distance".
Now the thread is starting to pick up a bit, good!
I have never worked with concrete before, so I'll have to read up a bit on the actual fastening element. There seem to be a few different options, at least three, as I understand it.
x Plug + screw (most common method?)
x Expansion screw (like the one Mikael_L linked to)
x Concrete screw (recommended by the Byggingenjören)
After a short research, I think concrete screws look the most interesting since they don't create a big explosion force, which reduces the required edge distance.
http://www.wgprodukter.se/Betongskruv(1).asp
I have never worked with concrete before, so I'll have to read up a bit on the actual fastening element. There seem to be a few different options, at least three, as I understand it.
x Plug + screw (most common method?)
x Expansion screw (like the one Mikael_L linked to)
x Concrete screw (recommended by the Byggingenjören)
After a short research, I think concrete screws look the most interesting since they don't create a big explosion force, which reduces the required edge distance.
http://www.wgprodukter.se/Betongskruv(1).asp
Expansion bolt provides very high explosive power, so if you meet its edge distance requirements, it should work for all screw (and plug) types.
Do you have ordinary concrete in the wall then?
Do you have ordinary concrete in the wall then?
Unfortunately, I don't know, is there an easy way to check this?Mikael_L said:
But does it really matter, does it not work to use the above methods for all types of concrete?
Yes, new holes are a way to get closer to the edge... Interesting info about the reinforcement.ingemar_o said:
The reinforcement is probably much closer to the surface than 50mm. Which is good, because you will likely get inside the irons with the drill.
But 50mm from the edge is the closest you should drill. Even there can, however, explode if you hit a larger stone in the wall.
But 50mm from the edge is the closest you should drill. Even there can, however, explode if you hit a larger stone in the wall.
We have lived in a condo in a concrete building from the 60s, with sturdy walls containing a lot of stone and thick reinforcing bars. Those walls were the reason to buy a hammer drill because regular drills would just burn out without making a hole.
We have also lived in 2 stone houses (concrete hollow block or aerated concrete), which is the experience I built my 300 mm on.
I have drilled closer than 50 mm without the corner cracking, but also 150 mm and still cracked the concrete. You can't know what the wall looks like with previous cracks, stone, reinforcement, etc., that might either crack the corner or hold it together.
You want a TV to stay in place, so I wouldn't take a chance.
We have also lived in 2 stone houses (concrete hollow block or aerated concrete), which is the experience I built my 300 mm on.
I have drilled closer than 50 mm without the corner cracking, but also 150 mm and still cracked the concrete. You can't know what the wall looks like with previous cracks, stone, reinforcement, etc., that might either crack the corner or hold it together.
You want a TV to stay in place, so I wouldn't take a chance.
I might be excessively oversizing, but a plate behind, where the mount is attached with countersunk screws from the back of the plate? You'll probably need up to 4mm thickness on the plate to fit countersunk M6 screws, but it should hold... Then you could paint it the color of the mount or the wall.
That way, you can reach all the way into the corner.
That way, you can reach all the way into the corner.