$1.$ A screw clamp similar to the one shown in the figure has a handle with diameter$3/16$ in made of cold$-$drawn AISI $1006$ steel. The overall length is $4\mathrm{.}25$ in$.$ The screw is $3/4$ in $10$ UNC and is $8$ in long. Distance A is $3$ in The length of the handle is $4\mathrm{.}1875$ in$.$ The clamp will accommodate parts up to $6$ in high. The screw has a square profile.

$($a$)$ What screw torque will cause the handle to yield? $($Answer Should be Approx. $27$ lbf$$ in$)$

$($b$)$ What is the maximum clamping force $($leading to handle yielding$)$ if the collar friction is neglected and if the thread friction is $0\mathrm{.}15?($Answer Should be Approx. $390$ lbf$)$

Problem $8-7$