How to Build Your Own Boat Lift

    Cut one end of each of the 5-foot and 10-foot "I" beams at a 45-degree angle with the cutting torch. Weld a 5-foot "I" beam to a 10-foot "I" beam at the cut edges of the beams. Repeat this process with the additional "I" beams to form the davits.

    Use the drill press to drill 1/2-inch holes in each corner of both steel plates. Weld a flat steel plate to the bottom of each 10-foot beam.

    Weld a steel eye bolt onto the end of the 5-foot "I" beams. This eye bolt will be used to suspend the riven tackle.

    Bolt the davits to the dock walkway or pier. The davits should be one boat-length apart, based on the length of your boat.

    With the line, reeve a twofold purchase in the blocks. Hang the blocks from the eye bolts on the davits. Screw an eye bolt into the forward structural member (the stem) and into the after structural member (the main frame or transom frame) of your boat.


  • When you wish to lift your boat, bring it alongside the dock walkway or pier, attach the boat falls to the eye bolts on the front and rear of the boat, and raise the boat using the falls.


  • Working with welding, cutting and drilling equipment carries its own set of hazards and appropriate caution is urged. Do not attempt to lift an occupied boat from the water.

Things Needed

  • 2 steel "I" beams, 4 inch x 10 foot
  • 2 steel "I" beams, 4 inch x 5 foot
  • 2 Flat steel plates, 6 inches x 6 inches x 1/2 inch
  • Cutting torch
  • Welding machine
  • Drill press
  • 1/2 inch steel bit
  • 2-sheave blocks
  • Nylon line
  • Steel eyebolts

About the Author

Will Charpentier is a writer who specializes in boating and maritime subjects. A retired ship captain, Charpentier holds a doctorate in applied ocean science and engineering. He is also a certified marine technician and the author of a popular text on writing local history.