The monster truck play fort is something me and my son have been talking about for several years and after I got my hands on a set of six foot tall tractor tires we had to make it a reality, so I drew a rough set of plans and got started. I set four posts in concrete, we used some logs from a friend's property, and built a lifted platform on the posts. The truck body was framed up with 2x4's, sheeted in plywood, and painted. A trap door was built into the floor of the platform, and a ladder was made from 2x4's. We lag bolted the tires to the monster truck fort platform, we filled the bottom of the tires with sand, so my son could play with his toys in them.

Step 1: What You Will Need

4 huge tires.
4 sturdy posts, we used logs.
16 80lb bags of concrete.
2 16ft 2x6's.
11 8ft 2x6's.
52 8ft 2x4's.
36 4in 3/8 lag bolts with washers.
4 4ftx8ft sheets of plywood flooring.
8 4ftx8ft sheets of OSB for the walls.
Nails and wood screws, 3in-3.5in for framing and 1.5in-2.5in for securing plywood.
3 gallons of Paint or stain to provide some waterproofing.
Wood cutting saws, we used a compound miter saw, circular saw, and a reciprocating saw.
Drill and bits,
Ratchet and socket to drive in the lag bolts.
Hammer and pneumatic nail gun.
Shovel.
Tape measure.
Level.
Carpenters square.

Step 2: Set the Posts

We partially builft the frame for the platform and used it to mark the location of the post holes. We dug 3ft deep holes and set the posts in place. We did our best to get the logs level and square and filled the holes with roughly 4 bags of concrete per hole.

Step 3: The Platform

We lifted the platform in place and temporarily attached it to the posts with framing nails, we then leveled the frame and lag bolted the frame to the posts with six lag bolts per post. I then cut the top of the posts off with a reciprocating saw. We finished framing in the platform and added bracing and supports, some of the bracing will be used latter for the trap door. Plywood was laid out on the frame and nailed down. Due to incoming thunder storms we did some early painting before completion.

Step 4: Frame Up the Truck Body

The truck body is made up of three sections to be framed in; the bed, the cab, and the engine bay. Each section was framed up in small sections, nailed to the platform and screwed together. When framing was complete the truck body was skinned in plywood. The engine bay is three 4ft x 4ft half walls, the cab is two 6ft tall and 6ft wide side walls and two 6ft tall and 8ft wide walls for the front and rear of the cab, and the bed is two 4ftx6ft side walls and a 4ft x 8ft wide tailgate.

Step 5: The Trapdoor

Using the added braces between the frame joists as a guide cut the trapdoor out from the plywood floor. Box in the the opening in the floor. Put the cut out back in place and add hinges. Drill a hole in the trapdoor on the opposite side from the hinges, string a piece of rope through the hole and tie knots in the ends of the rope to make a handle so the trap door can be opened from the inside of the fort. A ladder was then built and added under the trapdoor.

Step 6: Paint

Painting is time consuming, having a helper speeds up the process a great deal.

Step 7: Tires

The tractor tires were rolled into place and lag bolted in 3 spots to our monster truck. We filled the tires with sand, as a makeshift sand box. Remember to drill some drain holes in the bottom of the tires before adding the sand.

Step 8: Finishing Touchs

We added some old parts I had laying around to finish up the project. We added an old pickup grill to the front, and a set of license plates. A steering wheel and taillights will be added later, when i get my hands on some spares.