Just wanted to follow up on the failed Quick Adjusting Groove Joint Pliers from HD.
These came apart while I was pushing in the adjusting button and before I had even tried using them. Better to have it happen earlier than later, I suppose. At $10 for the set, I'm not surprised.
In the first photo the top pliers are intact. You can see the failed adjusting mechanism on the pair below it and some of the parts that fell out.
The second pic shows the parts that compose the release mechanism. When assembled, the shaft (2nd from the left) fits through the pawl that you see in the frame of the pliers.
The last pic shows the part that failed. Part #2 is a shaft that is simply press fit into the button #1 as shown. There is nothing more to hold these two parts together.
The shaft I mentioned above has a spiral-cut groove that engages with a pin on the internal pawl and serves to retract the pawl from the teeth on the frame when the button is pushed. The spring #4 sits outside this shaft and inside the frame of the pliers. It returns the button to its extended position when the button is released. The retaining nut #3 is screwed onto the shaft on the opposite end of the button and serves to hold the entire assembly in place.
Obviously, there are multiple possibilities for this mechanism to fail... and it did.