My last homemade anchor(Mighty Mite knock-off) was lost due to an unfortunate mishap involving reverse gear and my pickup truck. Fortunately my tire survived. I had leftover materials from the last anchor so the replacement cost was $0. I enjoy making crap in my garage so this really wasn't about saving money. Figured I would share the process so I took a few pictures. Sorry about the blurry one. Hope you find this useful.
17" x 1.5" ID anodized aluminum pipe scrap from a local marine fabricator(Free).
12' x 3/8" aluminum rod scraps from Scrap All($5).
Lead tire weights from Tire Kingdom(free).
Two 12" pieces of rebar scrap.
Chop saw with metal blade or hacksaw
Propane burner or Coleman stove
Long needle-nose pliers
Stainless steel camping cup
Vise Grip Pliers.
Cut a piece of aluminum pipe 17"
Anneal the aluminum rods where you plan to bend them. Heat the rods with the propane torch for several minutes then cool them quickly by dipping in a bucket full of ice water. The colder the better. The aluminum will harden again slowly over time.
Bend the first rod. I use two pieces of rebar clamped about 7/16" apart in the bench vice to aid in bending the rods. A few whacks with a hammer or mallet will help should you encounter a stubborn spot.
Bend the 2nd rod. Make sure the overall length is 3/8" longer.
Attach the two bent rods at the top using two cable ties.
Make the 5th tine longer so it sticks out at the top of the anchor. The extra loop will keep the rod firmly anchored in the molten lead.
Assemble the rods as shown. Use a cable tie at the bottom to hold everything together temporarily. Arrange the tines so they are equally spaced.
Slip the pipe over the rods. Cut and remove the bottom cable tie so they fit. The top cable ties will burn away in the molten lead.
Flip the anchor over and stuff a wad of aluminum foil in the bottom. This will keep the molten lead from pouring out the bottom.
Flip the anchor back over and fill with molten lead tire weights. I melt my lead in a stainless steel camping cup placed on a propane camp stove burner. Vise Grip pliers make a great removable handle for the cup. Don't clamp them on until you are ready to pour. I use the needle nose pliers to remove the tire weight steel clamps and crud from the molten lead. Do this outdoors on a windy day or use a strong fan to blow away the fumes. Move far away while the lead melts so you don't breathe the fumes.
Turn the anchor over and remove the aluminum foil plug with needle-nose pliers after a few minutes. Use a damp towel or welding gloves or you will burn the crap out of your hands. Fill the bottom of the pipe completely with lead. Allow to cool.
Close up of bottom.
Finished anchor with galvanized chain and shackles. The tines will bend if the anchor hangs up. You can bend them back into shape with a DeadBlow hammer. Never had a tine break until I drove over the last anchor with my truck. Oooooops!