I freed the lower jaw overnight, and there is now very limited movement in it - a few thousandths. "Why", I asked myself.
I found the answer when I compared the cheaply made Western Auto wrench with the Bonney wrench. The answer lies in the compromises made in designing thr Western Auto wrench to keep costs down. The Western Auto wrench makers may not have fully incorporated tool steel strengths in designing their wrenches,or they may have used inferior grade "tool steel", and had to compensate for that. Whatever the reason, the Western Auto wrench has a wider handle and a thicker upper jaw than do the comparable Bonney and Crescent wrenches. The wider handle in the Western Auto wrench limits the wrenches jaw arc.
You get what you pay for. Wider handles in the Western Auto wrench limited the arc of the spring-loaded jaw to near zero. But it must have been good enough for the Western Auto customer at the time. If the customer knew Bonney and Crescent small monkey wrenches of the 1920s and 1930s, he might have recognized the differences in finish between those wrenches and the Western Auto wrench. More likely, a Western Auto wrench customer probably did not recognize any difference in performance quality between the two classes of wrenches. Buying a 6-inch monkey wrench at Western Auto, however, must generally have been an expedient, one conditioned as much by circumstance as by cost.
