This is not exactly a tool but a replacement part to a handy tool. I have a Bissell Spot Lifter rug scrubber with a broken plug for its solution cleaning tank. The Bissell Spot Lifter cleaning solution tank plug holds the carpet cleaning solution in place while deep cleaning spots from the carpet. Bissell has the plastic replacement parts for the tank plugs built before and after 2003. I ordered both types but neither type had the correct threads. Manufacturing a replacement plug would have been an excellent project for those with 3D printers.
I decided to take a different approach by keeping the threaded end and replacing the rubber seal end. Using my 12” swing lathe, I machined off the broken end where the rubber seal is located, produced a short shoulder, and preserved the plastic threaded end. I held the threaded end in the lathe chuck using a slit section of thin wall stainless steel pipe. Lacking any 2” dia. aluminum stock, I cut a 2” x 2” section from a 3/8” aluminum 6061-T plate, drill a 1/2" hole in the center, and mounted it on an expandable mandrel for turning it down to a 1.7" OD . Using the 3” swing Unimat, I finished the part to a 1.6” dia. x 0.250” donut-shaped part with a groove for a number 218 Buna-N (Nitrile) O-ring. The salvaged threaded part was attached to the new aluminum section with cyanoacrylate (Super Glue). The replacement plug works well.