Early in the irrigation season, Mary turned on a DripWorks Micro-Flow Valve, only to have the knob + stem pop out and release a stream of water in the wrong place. Mary jammed it back in place until I could chop out the offending valve and install a known-clear replacement.
The knob broke off the stem when I tried to pry it out of the valve body:
The lip around the inside of the cap snaps over the top of the body, which is why I wrecked the stem, but the chip broke off the cap while Mary was turning it just before the stem popped out. Her fingers are barely strong enough to turn the valve, which means something had gone wrong before she started turning.
A look straight into the valve body:
The stem has swarf left over from drilling out the mold flash last year:
All in all, the Dripworks drip irrigation system works well, but their overall attention to QC leaves something to be desired.