Can the drywall really handle the load?

[Johan Lorentzon]

I am going to mount a TV with a swivel arm. The only place it works to put it up is a plasterboard wall. The plasterboard covers an area where a door used to be, and there is no stud installed between the former door frames.

The TV weighs 25 kg.
Molly plug M6 has a load capacity of about 35-40 kg per fastening and the wall bracket should have 4 fastenings. That is, the mounting as such should withstand >140 kg. However, due to the swivel arm, the load becomes significantly greater than 25 kg (lever effect). Additionally, the wall bracket is a relatively narrow vertical piece (about 300x45mm) which provides a very focused load on the wall.

I am worried that the plasterboard will not withstand this. Is my fear justified? If so, what can I do?

 

[Düsseldorff]

Single or double plasterboard? Chipboard behind or not?

 

[Stefan1972]

I probably would have sought another solution... it might hold for the moment, but there's nothing worse than when it eventually starts to come loose and possibly falls to the floor.
Or make an MDF board that you can mill nicely, which is considerably larger and can be mounted with expanders in the corners, then you attach the mount to it.

 

[Kane]

Molly plug M6 has a load capacity of about 35-40 kg per fixture, and the wall mount should have 4 fixtures. That means, the mounting itself should withstand >140 kg. Due to the swing arm, however, the load becomes significantly greater than 25 kg (lever). Additionally, the wall mount is a relatively narrow vertical piece (approx. 300x45mm) which gives a very focused load on the wall.

They can withstand 18 kg horizontally so you have to calculate the levers. How high is the mount? How far can the TV be pulled out?

 

[Dublin]

Take down the plasterboard, set up studs at an appropriate height, put the plasterboard back. A bit more work, the advantage is that you might be able to arrange some hidden cabling if you're opening the wall anyway.

 

[Kane]

This M5 from Essve can withstand 25 kg horizontally.

 

[Hubbe73]

Tests I have done for such mounts indicate that a standard gypsum board can support approximately 70-100kg of load per section if the fastening points are reasonably close to each other. (Note, not per fastening point) So calculate the tension load you get on the mounting with your bracket. (load x max protrusion, divided by the distance between the upper and lower fastening points in the wall.) If you exceed that, you should try to distribute across two different sections, or preferably hit the stud with one of the fastenings.

 

[Stefan1972]

Even so, it's not just the weight one has to consider. With such a narrow mount, it will slowly start to move if you swivel the TV to the sides. Eventually, the plaster might start to crack, causing it to move even more. That's why a wooden plate behind is better as it spreads out the mounting points so they are 3-5 dm apart, and then you have something solid to attach the mount to.

 

[Johan Lorentzon]

Single or double gypsum board? Chipboard behind or not?

The gypsum board seems to be about 15mm thick - no chipboard behind.

They can withstand 18 kg horizontally, so you'll need to calculate the levers. How high is the bracket? How far can the TV be pulled out?

The bracket is 30 cm in height. The TV can be pulled out about 65 cm.

 

[Düsseldorff]

The drywall seems to be about 15mm thick - no chipboard behind.

Then I would reconsider. The leverage when you pull it out to the max and the sideways movements will eventually damage the drywall, even if it initially handles the weight. If it's absolutely this mount you must use, I would open the drywall and place a stud behind. Or, possibly less aesthetically pleasing, put a plate on the wall to distribute the weight and reduce movement.

 

[useless]

Place a suitable disc on the wall and attach the arm to it.

 

[Kane]

The mount is 30 cm in height. The TV can be extended about 65 cm

Then the horizontal load is theoretically 55 kg at the top of the mount if it were to be attached with a screw there and one at the bottom. Are the 4 mounting screws aligned vertically?

 

[Johan Lorentzon]

Then the horizontal load theoretically becomes 55 kg at the top mount if there were a screw there and one at the bottom. Are the 4 mounting screws arranged in a vertical line?

They are more or less arranged in a vertical line, yes.

 

[mattoys]

I am going to set up a TV with a swivel arm. The only place where it works to mount it is a drywall. The drywall covers an area where a door used to be, and there is no stud installed between the former door frames.

The TV weighs 25 kg.
Molly plug M6 has a load capacity of about 35-40 kg per mounting and the wall mount should have 4 mountings. Thus, the mounting itself should withstand >140 kg. Due to the swivel arm, however, the load becomes significantly greater than 25 kg (lever effect). Additionally, the wall mount is a relatively narrow vertical piece (about 300x45mm) which gives a very focused load on the wall.

I am worried that the drywall won't withstand this. Is my fear justified? If yes, what can I do?

[bild]

Do you have to use that specific wall mount?
There are others with wider mounting points.

https://www.netonnet.se/art/tv/tv-tillbehor/vaggfaste-tv/andersson-wma-3-6/1006157.9106/

 

[Kane]

They are more or less in a vertical line, yes

Then there won't be much load per Molly. If the attachment is not in the middle of the plate but reasonably close to a stud, I would go with 4 Molly.