How to Build a Trailer Dolly

••• boat trailer image by wiladayvo from Fotolia.com

A trailer dolly is a practical accessory for anyone who owns a small trailer. The dolly allows you to move a trailer short distances by hand and maneuver it in tight places. A typical trailer dolly consists of a T-bar handle and arm that connects to an axle with dual wheels. A trailer ball attaches to a tower above the axle. A stand below the handle arm keeps the handle elevated for convenience. You can build a trailer dolly using steel channel and standard hardware.

Cut a length of 1 1/2-inch-wide-by-3/4-inch-deep steel channel 48 inches long to use as the handle arm. Cut another piece of channel 24 inches long as the axle frame. Use a miter saw with a metal cutting blade to cut the steel channel.

Center the axle frame at one end of the handle arm with the 1 1/2-inch-wide face of both pieces up. Weld the connection and allow the weld to cool. Lay the handle arm and axle frame flat with the faces of the channel up.

Cut a piece of 3/4-inch steel pipe as the handle. Center the handle across the end of the handle arm opposite the axle frame. Weld the connection and allow the weld to cool.

Turn the handle and axle frame assembly over. Cut two pieces of channel 12 inches long as the legs for the dolly stand. Place the pieces on edge and configure them to make two sides of a 12-inch equilateral triangle. Weld the pieces at the point of the triangle.

Position one leg of the stand at the intersection of the handle arm and axle frame. Position the end of the other leg on the handle arm. Weld the legs of the stand to the handle arm.

Cut a length of 1/2-inch-diameter threaded rod 30 inches long as the axle. Center the axle inside the channel of the axle frame with 2 inches of the axle extending from the frame at each end. Weld the axle to the axle frame.

Put a nylon washer and a 9-inch wheelbarrow tire on each end of the axle. Put another nylon washer on the axle against each wheel hub. Thread nylon lock nuts on the ends of the axle and tighten the nuts with an adjustable wrench. Turn the dolly over and rest it on the stand.

Cut two additional pieces of steel channel 12 inches long as legs for the trailer ball tower. Weld the ends of the pieces as before to make the point of an equilateral triangle. Position the legs of the tower atop the axle frame. Align the point of the tower with the center of the handle arm and weld the legs to the axle frame.

Position the trailer ball at the point of the tower with the ball up. Weld the threaded-stem end of the trailer ball to the top of the ball tower.


  • Wear the proper safety equipment when welding.


  • Select the diameter threaded rod based on the size of the axle hub of the particular wheelbarrow tires.
  • Use nylon washers and castle nuts that fit the threaded rod.
  • Prime and paint the dolly for rust protection.


About the Author

William Machin began work in construction at the age of 15, while still in high school. In 35 years, he's gained expertise in all phases of residential construction, retrofit and remodeling. His hobbies include horses, motorcycles, road racing and sport fishing. He studied architecture at Taft Junior College.

Photo Credits