Wavian Water Jug Wrench

thingiverse

I bought a Wavian water container along with their wrench to remove the cap, as high altitude pressure changes or someone tightening the cap too much might make it hard for others to take off. When showing the container to a coworker, we noticed that the wrench fits snugly over the attachment strip (first photo) and the strip is changing color, indicating it's being strained and work-hardened, which means it will eventually break down. One coworker suggested cutting the existing wrench while another said I should design a wrench with a gap to clear the strap. Since I didn't want to cut up a good wrench, the second photo shows my attempt to create a wrench with a cutout. The broken version is what happened when I printed it with inadequate settings: infill was set to 30% triangle and 3 layers. It handled most of the twists and flexing but broke when subjected to rough treatment. The lower one was printed with 5 layers and 60% infill, making it much more robust. You can still break it, but you have to be trying hard. The third photo shows the proper way to turn the wrench: move the handle in the direction of the opening so that it compresses down on the cap. I've seen many people turn it the wrong way and it hasn't failed yet, but I think it's better to do it right. Photos 4 and 5 show how the other end of the wrench is designed to fit the plug Wavian uses for attaching its spigot, which is located under the cap. The final photo is for anyone who wants a full-strength version of the wrench: I printed these wrenches in glow-in-the-dark ABS, making them easy to find at night.