I do not have a marina near my place at the lake - the nearest two are 30 miles in either direction by road. After doing some research I decided using a train wheel was the best anchor for my mooring buoy. I was able to secure an 800 lb scap train engine wheel (below) for only $40 at the local steel mill. They even loaded it on a pallet onto my utillity trailer. I knew someone who worked there.
I bolted scrap railway tie plates like the ones below on either side of the hub hole of the wheel with heavy bolts about nine inches long. On one plate I had also bolted on a heavy eyebolt. The plates are almost an inch thick. I shackled a heavy chain about 20 feet long onto the eyebolt and shackled the other end onto the swivel of my mooring buoy.
I had the marina across the lake make me a very nice pennant rope over 30 feet long so that it easily reaches from the bow to the swim platform. This allows me to pull up the buoy on the swim platform to connect the pennant to the swivel on the bottom of the buoy.
Once everything was connected, I backed up the trailer to the boat launch and slid the pallet with the train wheel on it onto my neighbor's PVC floating swim platform which I then towed out to the mooring location in a slightly sheltered bay in front of my property. There I pushed the pallet off in about 7 feet of water. I had hoped that the train wheel would sit flat on the bottom with the eyebolt up, but when I inspected with my snorkel it went down right on edge. It is probably close to 4 feet in diameter and only about 6 inches was sticking out of the mud. I won't get the desired suction action of the having it sit flat, but this thing is not going anywhere.
We get serious ice on our lake so this fall I removed the buoy, bolted a cable to the chain and ran that on the bottom to shore where I tied it to a tree. The ice can take out a mooring if it is left to overwinter.
I am very happy with the result so far. I usually just take a canoe or kayak out as my tender. Sometimes I even swim. I have solar mooring lights for night. I can keep an eye on it from my deck:
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