When constructing a utility trailer or even one specifically built for a single purpose, consider making it into a "tilt" trailer. The tilt feature can increase the usefulness of the trailer, eliminate the need for special ramps to load and off-load equipment and extend the life of the trailer's deck by insuring rain and snow will run off, rather than sitting on the deck when it's stored in a level position.
Draw up the plans for the trailer and use the dimensions to determine the amount of materials to purchase.
Determine the maximum load that will be carried on the trailer. That will dictate the size of wheels, axle and suspension springs needed, as well as the size and strength of the steel that will be used to construct the trailer chassis and deck support framework.
Purchase a length of U-channel one foot longer than the distance from the trailer's axle to the front of the trailer's deck. The U-channel needs to be sized so the steel tubing used to make the trailer's tongue will fit inside the "U" of the channel.
Purchase an additional length of whatever sized steel tubing is used to form the trailer's chassis, long enough to span cross ways from one side of the chassis to the other.
Purchase enough steel tubing for the trailer's tongue to extend from the coupler to the front of the trailer, then on back to 4 inches ahead of the position where the axle will be located.
Cut all pieces of chassis steel, lay them out and weld them solidly.
Weld the additional chassis cross member 4 inches ahead of the position where the axle will be located.
Lay the tubing for the trailer's tongue into the U-channel so that one end of the tubing and the channel are even.
Drill a 5/8-inch hole 2 inches from the end of the U-channel/tongue steel with the tubing nestled into the channel. Center this hole half way from the top to bottom on the U-channel. Drilling both pieces of steel at the same time will ensure the holes will line up exactly.
Insert a 5/8-inch bolt into the hole, just drilled, through both the tubing and U-channel to ensure the holes stay lined up.
Drill a second 5/8-inch hole through the U-channel, again with the tongue tubing nestled inside it. Drill this hole 2 inches from the opposite end of the U-channel, centered half way top to bottom. Just as before, drilling both pieces of steel with one stroke of the drill press insures the holes will line up perfectly.
Remove the bolt from the tongue/U-channel assembly to separate the two pieces.
Center the U-channel on the bottom of the chassis cross member positioned just ahead of the axle and to the underside of the cross member at the front of the trailer deck so the open end of the "U" will be pointing down toward the ground when the trailer is upright. Weld the U-channel securely to the frame and cross member.
Attach the trailer coupler to the undrilled end of the trailer tongue tubing.
Bolt the tongue at the end of the U-channel into position under the trailer with a 5/8-inch bolt and lock into place with a 5/8-inch hitch pin in the holes just ahead of the deck of the trailer. The 5/8-inch bolt is the tilt system pivot point and the hitch pin is the lock-down mechanism.
Finish assembling the trailer by attaching suspension, axle, wheels, and adding sides, tie downs, jack-stand, lights, fenders and any other custom features desired.
Paint the exposed steel with rust resistant paint.
Attach the deck boards.