This is a common water meter as found in the USA. Notice the white arrow. Just above it is the shut off valve. The photo is from Google Images. My meter is in a much deeper hole and the valve is much more difficult to reach for those times when I need to do a plumbing repair in the house and need the water to be "off." This Instructable will describe the water meter key I made from scraps welded together.
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Step 1: What You Can Buy
This is a commercially available water meter key. They are not very expensive, but I have a welder and had some suitable scraps materials on hand.
Step 2: The Working End of the Key
The end of a commercial meter key is a "U" shaped piece welded onto a long rod. This photo from Google Images shows a commercially produced key on the shut off valve. Most commercial keys are painted black.
Step 3: My Finished Meter Key From Scraps
This is my finished key that I made from six short sections of various kinds of tubing plus the piece for the handle. The door knob gives you and idea of its length. Because our meter is deeper than usual, I needed a longer key than is usually found in the local hardware store.
A note on use of the water meter key: In our part of Idaho we have little rainfall. Our water for irrigating our lawns comes through a system of underground piping about 10 inches in diameter. It is fed by water in reservoirs from spring snow melt in the mountains. Once a week we open the valves in the backyard and flood the entire lawn with about 3 inches of water. The meter box fills with irrigation water and the shut off valve silts over so that it is not visible. My longer meter key is handy for poking around to find the shut off valve in the muddy silt.
Step 4: Making a Straight Shank
The shank or shaft of my key is made of some square tubing and some round pipe. My favorite method for welding such pieces so the end product is straight involves a piece of aluminum angle someone gave me. Its valley holds pieces in alignment until I can tack weld them in place. Also, if I accidentally touch the aluminum with the electrode, nothing sticks to it.
Step 5: The Handle
It would have been good to have the handle just a little longer, but this is the piece of scrap I had available, and it works well enough. Some of the scrap pipe sections had been used to practice welding beads.
Step 6: The Working End of the Key
To make the key end I attached a 10 inch abrasive cutting wheel to an arbor and manually worked the end of a 1 inch piece of pipe against the edge of the wheel until I had a slot that would fit over the shut off valve in our water box. That would have been sufficient, but I wanted to add a little leverage and make the key easier to align on the shut off valve. So, I welded two small pieces of strap iron onto the end of the pipe.
I have not needed this water meter key often, but it works very well. And, I used up some scraps I had without a penny out of my pocket (other than for welding electrodes).