Long reach cantilever TV bracket fixings?

[Tarquintar]

I am putting a 55" OLED TV in the alcove next to the fireplace but in order to view it from several angles need to attach it via a 3 piece cantilever arm with a 700mm reach.
The wall is solid 9" brick covered with old plaster some of which has a gap behind. With this in mind I've bought Corefix 100 mm dot and dab fixings with the metal 'liner' to avoid damaging the plaster but now see there's some small print on the box saying these aren't recommended for cantilever brackets.

I'm a little bemused. There are images of people hanging off of TV brackets and I aim to use 6 x 100mm. Surely that's enough to support a 16 kilo Tv?

 

[noseall]

I am putting a 55" OLED TV in the alcove next to the fireplace but in order to view it from several angles need to attach it via a 3 piece cantilever arm with a 700mm reach.
The wall is solid 9" brick covered with old plaster some of which has a gap behind. With this in mind I've bought Corefix 100 mm dot and dab fixings with the metal 'liner' to avoid damaging the plaster but now see there's some small print on the box saying these aren't recommended for cantilever brackets.

I'm a little bemused. There are images of people hanging off of TV brackets and I aim to use 6 x 100mm. Surely that's enough to support a 16 kilo Tv?

The first thing I'd look at are the bracket hole spacings and the positioning relative to the (unseen ) brick joints. Chances are at least one or even two of those fixings may be unsuccessful.
However, I'd still put my faith in four good 100mm fixings any day.

 

[robinbanks]

Surely that's enough to support a 16 kilo Tv?

Go for it. You'll get warning signs long before total failure and worst case, that you hit a bed for every one of your top fixings, and they all pull out and you don't notice, you'll simply find a bent-down-and-hanging-off-the-bottom-fixings tv bracket. The bottom fixings won't pull out if they're very close to the bracket bottom so you won't be finding a tv smashed on the floor

 

[stevie888]

I'd not worry about 16kg hanging on the wall, but stick it 700mm out and you're putting serious tension forces on the top fixings and making the bottom of the bracket try to punch into the wall.

Solid brick is a much better prospect than d&d though which begs the question why the fancy fittings? I'd use resin anchors if it was mine.

 

[robinbanks]

Well, they aren't really fancy fixings are they? They're a screw and rawl plug, and an offcut of pipe to stop the fixed item's bottom edge crushing plasterboard by transferring the compression through to the solid substrate..
The fancy genius is in the marketing; selling 10 screws, plugs and bits of pipe for a princely sum because people want to mount a TV and not spend slightly more on 100 screws, 1000 plugs and a metre of pipe they then have to cut.

Resin anchors seem overkill for a 16kg TV, even at a 3:1 gearing (assume the backplate of the mount is about 233mm high) but they would also work

 

[Tarquintar]

Solid brick is a much better prospect than d&d though which begs the question why the fancy fittings? I'd use resin anchors if it was mine.

I have a tube of resin left over from another job and did think to widen a couple of the holes and squirt a bit in around a couple of the screws.

I've gone 'fancy' because, as Robin says above 'to stop crushing' in this case, the *plaster.

*the stairwell plaster had a shrinkage gap between it and the brickwork. I put a spade behind it, gave it a twist and the whole side cam down in one. That was 30 years ago, we're still cleaning up the dust. We skim coated the artexed living room and some bits of the wall bang like a drum and I hope the fixings will help bypass any issues.

 

[robinbanks]

the artexed living room

Did you have it tested for asbestos at the time? If not, you may want to send some for a test, and consider carefully your strategy for drilling into it.
(If positive I'd have a hoover running outside, pipe through the window, on a rainy day.. New HEPA bag, that is disposed of into an asbestos sack and taken to the local tip.. Hoover nozzle held next to the running drill bit, and a P3 mask on yourself and maybe even soak the wall before low speed drilling with an SDS..).

Ultimately, asbestos is naturally present in the environment thanks to decades of quarrying operations so people do intrinsically come into contact with it, and it's not anthrax.. but definitely worth taking particular precaution before filling a house with its dust

 

[Tarquintar]

Did you have it tested for asbestos at the time?

The wall was artexed a couple of months before we bought the house, which was 2 years after Artex stopped using asbestos. It has a skim coat of plaster on top and I'll be using an 'xtra hand' vacuum attachment to avoid any dust.