42" TV, double plasterboard wall, steel "I" studs - mounting help

[Jordanm]

Hello

I'm trying to mount a 42" LG TV to my plasterboard wall.

I have bought this bracket which has 3 holes for mounting in a vertical arrangement directly into a single stud. https://www.amazon.co.uk/gp/aw/d/B010G6972O/ref=mp_s_a_1_3?ie=UTF8&qid=1485375193&sr=8-3&pi=AC_SX236_SY340_QL65&keywords=tv+mount&dpPl=1&dpID=51+QzrBIzHL&ref=plSrch

One of the studs is located directly where I want the centre of the TV however they are I shaped steel studs. I don't think it is possible to drill into the centre of the stud due to the shape, see here http://www.buildingmaterials.co.uk/images/super/galvanised_i_stud_2.png

I have looked into using "gripits" however the wall is double plasterboard - total thickness 3cm - therefore gripits will not work as the wall is too thick.

Any ideas or help on how I can get this TV securely on the wall would be much appreciated!

Thanks

 

[Lucid]

Given the wall construction I take it this is a partition wall and the thickness is about trying to keep noise to a minimum?

The bracket you have is a cantilever. That means the TV could be anything up to 50cm out from the wall. The weight of the TV plus the weight of the bracket plus any force you (or someone else) is putting on the TV as it is moved will act as leverage and try to prise the bracket off the wall. You haven't mentioned the weight of the TV. A 42" LG can weigh less than 10Kg or a lot more.

The Gripit site gives loadings for cantilever force (though the figures that give look a bit odd as the capacity goes up for a longer lever(!!) rather than down) and the tension force capacities.

You can solve the problem of the wall being too thick by sinking the Gripits through the top layer so they anchor in the back layer only. You'd have to make the front layer hole a bit wider to make this happen. However, that still leaves you with the problems of the I beam and calculating the leverage force, and the practical issue that the bracket requires a vertical line of holes in the very substance that's sopposed to be providing the strength to support the TV bracket.

If it was me I'd change the bracket to one that spreads the load over a wider area rather than concentrating in one small zone. It doesn't have to be this particular one, but it should give you an idea of what I mean. That then potentially solves the alignment class issue. Using a bracket with a larger wall plate also means spreading the load over more Gripits, so a lower load per Gripit.

 

[rules&rulers]

Never been a fan of cantilever tv brackets,i have fitted these brackets http://www.screwfix.com/p/sanus-universal-tv-wall-mount-fixed-22-50/4079j
with M6 or M8 60mm spring toggles.
good luck.

 

[foxhole]

Toggle bolts thru the wall will hold it, fixing a slim section of ply to the wall under the bracket with them, then screw thru the lot.

 

[JohnD]

I would have thought large self-tappers into the webs of the stud would be best for taking the weight, but with a wider plate to spread the sideways twisting load into the plasterboard, at the maximum possible width. The webs look very thin so will probably bend under twisting load.

If the plate, or a ply board, is decorated to match the wall, and is behind the TV, it will not be an eyesore.

The bars linked by creamcrackers look like they could span two studs, which would be the best way, not relying on the plasterboard.

I once ripped a hospital radiator off a drywall when I fell off my crutches.

 

[ericmark]

I had a similar problem 43" TV and a mother who will likely pull any TV off a table, I went to the "Range" and bought this TV stand it was not easy to assemble, however it does mean TV held firmly and no wall fixings required, and cables to set tops boxes are hidden from view.