That was definitely an issue in the project I¡¯ve been working on. ?Crazy teens, drunken old men arguing politics. ?I did the weight analysis like Mark evidenced, but the client was afraid his kids would rip it off the wall, so we went a bit beyond.
David Best
https://www.instagram.com/davidpbest/
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And then there is the occasional young kid or an old young at heart kid that wants to hang from the floating mantle ????
Imran?
On Jan 6, 2021, at 4:49 PM, mark thomas <
murkyd@...> wrote:
?A little math, and envisioning of the physics can also be useful.? Your mantle timber weighs about 130 pounds (2.8 cu ft x 45#/cu ft). Assuming studs on 16" centers, you'll have three studs to attach to, so each stud attachment point is carrying 43 lbs.? You can envision the attachment forces as hanging a 43 lbs weight at the center of gravity of the timber, like this drawing.? There are downward shearing forces on the cleat (blue), tension forces pulling outward on the screw (red), and compression forces pushing against the wall (yellow)
It's probably intuitively obvious that these are not large forces and a simple french cleat is more than sufficient.??Also note that screws from the top into the cleat serve no purpose in Indiana (no earthquake there to lift the timber off the cleat, correct?)
<Screen Shot 2021-01-06 at 1.34.46 PM.png>
??
David P. Best