In the figure for Problem 13-35, pinion 2 is to be a right-hand helical gear having a helix angle of 30°, a normal pressure angle of 20°, 16 teeth, and a normal diametral pitch of 6 teeth/in. A motor delivers 25 hp to shaft a at a speed of 1720 rev/min clockwise about the x axis. Gear 3 has 42 teeth. Find the reaction exerted by bearings C and D on shaft b. One of these bearings is to take both radial and thrust loads. This bearing should be selected so as to place the shaft in compression. 

Data in Problem 13-35

Repeat Problem 13-34, using a 25° pressure angle. Take note of the effect of this variation on the overall size of the gearbox.