Design the bicycle wrench with the approximate dimensions shown in Figure P7-38. If you need to change dimensions explain why. The wrench should be made of steel or aluminum alloy. Determine the thickness needed based on the maximum distortion energy theory. Plot the deformed shape of the wrench and the principal stress and von Mises stress. The boundary conditions are shown in the figure, and the loading is shown as a distributed load acting over the right part of the wrench. Use a factor of safety of 1.5 against yielding. Round each corner with a 10 mm radius.

Figure P7-38

The sides of the middle hexagon are 9 mm long. R= 15 mm 1 mm rad. (typ.) 20 mm 40 mm 1 mm rad. (typ.) The sides of the corner hexagons are 7 mm long. 10 mm 10 mm 10 N/mm Fixed all the way around this hexagon.