OT: Structural Question

Mount a rectangle of 5/8" marine plywood or 3/4" hardwood across two studs, but angle the lag bolts 15 degrees upwards into the studs.

That sounds reasonable. The plywood will spread the force preventing it from crushing the foam.

But, when JT says 20" of lever, does that mean the set is not flat on the wall, but on an arm 20" from the wall? I think that could be very bad. I can't say how strong the stucco and foam are, but I think I would either make the wood tall to spread the torsion over a long area with a lot of lever arm or just punt and place the set a piece of furniture. A nice piece of plywood can be stained and trimmed to look attractive. Perhaps make a boxed frame of sorts. Using thick pieces for the trim can make it a lot stronger too.

How about some of the screws that have lag on one end and threaded to accept a nut on the other. Say 5 " long, 1-1/2" through stucco, 2" into

If I didn't describe it well, here's a partial drawing.

Mikek

maybe hanger bolts, you could put a nut behind the bracket instead of using sleeves.

another possiblily is a long screw at an angle to take the weight eg: a 3" or 4" #8 chipboard screw at a 45 degree angle, (upwards) drill the stucco (and drill a pilot in frame if hardwood), lube with liquid nails or caulk

Uh, outdoors where there is potential of water intrusion, I agree that 'up' angle is best, but if in dry/protected area, isn't 'down' angle better? Viewed from the side, thre's a natural 'hook' formed.

The bolt will survive the weather better than the TV will.

Up is better because it hangs the board against the wall material in a way that any yield in the wall produces less movement of the board with an increase in tension and little increase in side loading angle on the bolts. That is, they operate mainly in tension not in shear.

Make sure they're long enough to still hang in there after they rust a little and the wood rots a little, and put some grease or tar into the hold before screwing them in, against that.

A couple of pieces of timber from the TV bottom edge to ground to support the weight would make life easier.

Cheers

Mount the TV VESA mount plate to a square cut piece of MDF at 5/8 or 3/4 inch thick. Painted matte black or neutral grey of course.

Make a hanger for that, two vertical arms, and 'hang' the mount. Hang a bar at the TOP of the wall to make the hook rail for the hanger's vertical mounts. This also allows the vertical position to be adjustable, as your original choice may not be as appealing when in place as when you chose it.

That makes it easily removeable, and even more easily adaptable to a new location as well. Simply mount a new hook bar at the top of the wall at the new location.

Ideally, you'd like to spread that load over a large area -- taking into account additions to the load as the unit is moved, adjusted, etc. in normal use.

Stucco over wood tends to be more fragile than stucco over masonry. So, you risk cracking it as stresses get transferred to the wall surface.

On the cheap, I'd try mounting a large piece of plywood to the wall to distribute the weight a bit more evenly. But, this risks "things" getting behind the plywood (swarming termites, leaf cutter wasps, bees, ants), stains on the wall (when you remove the plywood, eventually), etc.

If you want to do it right, use several shoulder bolts in each stud and support a panel (plywood, etc.) *off* the wall surface. I.e., all of the weight transferred solely through the bolts *to* the studs. A clearance area around each bolt can be filled with paintable silicone (so the adjoining stucco never feels the motion of the hardware)

You can buy hardware that has a coarse wood thread on one end and a machine screw on the other end (thread a nut onto it and screw it into the stud using the nut to keep from marring the machine threads)

You can't really use very large hardware as you only have a 2x4 to play with.

If it was a *permanent* installation (i.e., you'll eventually replace this TV with *another* in the same location), I'd open the wall and install

(I did this, here -- smaller sale -- to reinforce the interior walls where I installed "control consoles" as well as areas where we hang artwork)

Or, hang the mess from ceiling/roof rafters (like a painting in a museum).

The hanger is one of those fold away from the wall plus tilt, so there's a "lever" load on the anchors.

Looks like my best bet is to build it out with a 2x2 which will get it flush with the stucco, then 4" lag bolts. ...Jim Thompson

That's why I suggested the clamp pressure on a sheet of plywood, it adds additional strength against any sag caused by leveraged weight.

A bolt at each corner will give it loads of strength to prevent sag. Paint it to match your stucco or black to match the TV.

hrumph!

Mikek :-)

That must be a good idea! I think there is just such a picture somewhere, just a minute I'll see if I can, oh, ya here it is.

Mikek :-)

Mikek

Those are referred to as "hangar bolts".

I cannot believe that nobody liked my "hang it on straps from a (heavy) towelbar up near the ceiling" suggestion. Stainless or chrome or flat black on steel... all would look OK. Makes it absolutely serviceable and safe too. Especially if the overwrap "hooks" have a closure tab to put a tie wrap through.

I can't believe no one liked my idea, well I looks like Don Y did, he's sees the advantage of compressing the plywood between two nuts with large washers on hanger bolts. :-) One in each corner should work, if Jim wants to over build he could 3 put on each side.

Mikek

What is on the other side of that wall?

Thinking of using a big-assed magnet? ;-)

What's the distance between the upper and lower bolt holes from the bracket to the wall?

The upper lag bolts will be under tension. The lower end of the bracket will be pushing into the wall. This is the point that washers can prevent the stucco from crushing.

If you build a frame (of 2x2s, Unistrut, etc.) between the TV bracket and wall, the greater distance between top and bottom wall attachment points, the lower the tension/compression will be.