I think i’m treading on really thin ice with this one… but lets see.
I was asked to install an LCD tv in a friends waiting room @ his office. Its a smaller 26″ LCD weighing just 32 lbs. The mount for it is an articulating arm, that can pull away from the wall about 18″. Now, here comes the questionable part… Due to its location, between a door and a inside wall corner, the mounting arm was not falling on one of the metal studs. So, I opted for 3 toggle bolts in nothing but drywall. Each bolt was rated for 90lbs in 1/2″ DW. I used three, if it had been a flush mount screen, with no arm, i wouldn’t question it, but the fact that it pulls away must change the loads quite considerably. In its current position, its about 8-10 from the wall. Do you think I should expect to be buying my buddy a new tv anytime soon?
-mike.
Replies
Yes.
Why don't you open up the wall and put some blocking in there.
that would require a paint job... i don't think he wanted that.
True, but if the TV is going to be there anyway, you could open up a small area get some blocking in there and feather the paint.
what's cheaper, painting a wall or replacing an LCD TV?
Isnt paint cheaper than a new tv?
neither of us really wanted to invest that much time. :-)
I know what you mean. I like the idea of using the plywood to span the studs on the outside of the wall too.
Ya never know, it may hang on those butterflys for years.
Good luck!
If you want to sl;eep better at night, use some wingits. These are special badmitten sized fasteners for grab bars. They make a smaller type for what you are doing.
Mike
thats what toggle bolts are, aren't they? they screw in, and the winged part comes out, and pulls back to the drywall when you screw it in.
Edited 5/6/2006 8:06 pm ET by MichaelJacob
No, WingIts are different from normal toggle bolts. Check out their website. They're pretty impressive, and are designed for non-shear loads, such as grab bars in bathtubs where no blocking was installed.http://wingits.com
No comparison between a toggle and a wingit.
Mike
i noticed this chart... paints a more positive picture when it comes to tension on the toggles...http://www.factsfacts.com/MyHomeRepair/images/ToggleBoltSpecs.gif
I would say yes, you will soon own a broken TV.
Put some backing in the wall, or a ledger board spanning studs and then mount the thing on there.
Mike
Trust in God, but row away from the rocks.
i've used the ledger across two studs method on a larger plasma. but the way this one is positioned there is only one stud between the corner and door, so i can't span anything....
Michael, surely that 90# is a shear amount, and this is not a shear load. Here is how I would figure it. If the vertical distance between screws is say 3", and the arm is as you say 18" . The bottom screw is the fulcrum. The 18" arm is six times longer than the 3" spread of the screws, so that 37# is now six times greater, or applying 222# tension or pull on the one or two top screws.
It is just a mater of time, and I am afraid the clock is counting down.
i like your calculations... they make a solid point for your argument... we'll see what happens... i'm not going back till monday. I better make the best of my weekend... it might cost me big $$$ :-)thanks guys.
Used to work in a museum and hung more than my share of tubes...block it up or you'll owe him a new tube...
Mike - Why not trace around the mounting plate and then cut a hole a little smaller then that. Slip in some wood blocking, put the rock cutout back, remount the plate and arm, covering all evidence of the surgery.
Plan B - Make a nice wooden plate up out of birch ply or whatever, maybe 20" x 20". Surface mount that to catch the studs. Mount tv bracket to that.
Good luck... Buic
One critical measurement missing: What is the distance from the topmost bolt(s) to the bottom edge of the bracket?
What might work instead of opening the wall is to install a piece of nicely stained plywood, and then mount the bracket on that.
Hey there Michael Jacob,
I've used wingets in "real high end" houses in the north shore area of Chicago just a couple of times simply because they were spec'ed but I came away a real believer. Those puppies hold like you would not believe.
And now after saying that I have to say I went back and reread your original post and realized you said " mount for it is an articulating arm, that can pull away from the wall about 18".
As someone who has "done that, been there, I gotta say that arm is actually a fulcrum and NO WAY is that mount going to hold up in just sheet rock. Wingits I believe would hold but sooner rather that later the drywall will fail.
What's the size of the mount. How far away from each other are the screws. What's inside the wall your working on?
I've seen my share of wall and ceiling system failures and none of them are fun. You go in there and even if it's not your fault--there are definitely no heroes to be found around failure.
If this guy truly is your "buddy" he should be able to understand your coming back and saying "after thinking it over I'm just not comfortable with they way I mounted the screen and need to beef it up some". I promise you he would greatly appreciate your honesty and integrity.
If he had YOU mount it for him it means HE doesn't have the skill, knowledge, and experience to do it and is counting on YOU his BUDDY to do him right and not stick it to him where the sun don't shine.
Just by your asking the question here, and then reading the replies I think you already know what to do. Let us know what happens.
Have a good weekend.
Cork in Chicago
failure mode will not be the fastner but pulling thru the sheetrock, in my pinion
okay, so i went back... the tv was still up on the wall, no obvious signs of failure yet... but in any case, i yanked it off the wall, found the lone metal stud, and sunk four 2" metal screws through the mount, all making solid contact with the stud. I really doubt there is any way it will fall off now. shudda done that the first time... i guess thats what separates us DIYers from the pros :-)thanks for all the advice guys.
-mike.
Yeah, the pros wouldn't have gone back.
If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy. --James Madison
I used to manage a custom A/V company. Whenever we hung a tv, the mount had to be capable of supporting the weight of one installer, two if liqour was availble. Make the thoughtless moron a part of your design process so there won't be surprises when they appear.
Yeah, I was installing wiring for studio lights once. Figuring that I'd be up there on occasion, adjusting the lights, I made sure that all the hardware was secure enough to support me if I slipped. (Of course, I've gained 50 pounds since then.)
If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy. --James Madison
Your toggle bolts aren't the weakest link here, are they? If this was a static mount that hugs the wall, you would be OK. Since it's an articulating arm, you aren't. Change the way it's mounted ASAP. If it will never be moved, maybe you could add a safety wire, attached to the metal top plate or the closest stud.
Ditto what the others have warned--18" lever prying on toggle bolts may hold up if it's never touched, but it may not. Not everyone who changes the direction of the tv will be gentle, so I'd be most afraid of that.
More importantly, the tv is in a public area so there is a higher level of care expected than if you simply had mounted it in his house. Not only would he get sued if it fell on someone's kid, but you might as well. Unfortunately for you, his liability insurance could argue that the installation was grossly undersuported (gross negligence) and they wouldn't pay a dime, which then leaves you as the target with the second deepest pockets, even if you did it for free.
At the very least I'd extend a small bracket or even 1/16" wire cable to a stud so if it does fall, it won't be able to hit the ground.
Having said all that, if it's piece of mind you're looking for and changing anything is a total pain in the ars, do a mock up on a wall with a similar bracket, stud spacing and toggle bolts, and pull on it until it comes free. You may be pleasently surprised how tough it is, or shocked at how easy it came out.
Hope for the best, plan for the worst.
I'd start pricing LCD TV's.
90lb toggle bolts are rated for shear load, not against pulling out. Your 32 lb TV, extended 10 inches, is exerting about 30 foot-pounds of torque (48 lb at full extension) against about two square inches of drywall that has been weakened by drilling a big hole in it in close proximity to two other big holes.
Can you cut a piece of 1x6, run a roundover or cove router bit around the edges to make it look finished, screw it to the studs on both sides and mount the TV on that?
BruceT
I wouldn't trust 1x6 in that duty.
If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy. --James Madison