Do It Yourself Flatbed Kits for Your 1/2 Ton Pickup Truck

by William Machin

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The creative wheels are turning as you look over your 1/2-ton pickup truck with the bed removed. You have some aptitude for woodwork and metalwork, you have the tools and you want to save the cost of a production flatbed kit. A DIY flatbed kit includes a steel frame that you sheet with diamond plate or fit with framing lumber. The front wall of the old bed provided protection for the rear of the cab. Your flatbed kit should similarly include a bulkhead at the front to protect the cab.

Rails

Step 1

Make a design plan for the flatbed. Include dimensions for overall width, length and the height above the truck frame for tire clearance. If you have side rails or plan on making them, include locations for the slots. Decide on the height and configuration of the bulkhead.

Step 2

Select steel I-beam or wood header material for the base rails that run from side to side. The height of the material is established by the tire clearance. Cut the rails to length.

Step 3

Position each rail across the truck frame and mark for attachment bolts. Drill 1/2-inch holes in the lower flange of the I-beam. Drill 1/2-inch holes through the wood header and make 1 1/2-inch diameter countersinks for the bolt heads. Attach the rails to the truck frame with 1/2-inch machine bolts, lock washers and machine nuts.

Diamond Plate

Step 1

Measure and cut 3-inch steel channel for the four sides of the flatbed frame. Cut intermediate pieces of channel that span the width at 12-inch intervals.

Step 2

Position the steel frame on a flat surface. Square the corners with a framing square. Weld the corners of the frame. Put the intermediate pieces in place and square the inside corners. Weld the intermediate pieces to the frame.

Step 3

Fabricate the bulkhead to your design and dimensions using square steel tubing. Weld the bulkhead atop the front rail of the frame. Allow the welds to cool. Grind the welds for a uniform appearance.

Step 4

Position the frame on the I-beam rails. Align the sides and ends. Cut one or more pieces of diamond plate to size. Position the plate atop the frame and clamp the edges using C-clamps.

Step 5

Mark locations for 3/8-inch carriage bolts. The bolts attach the diamond plate to the cross pieces, and the steel frame to the I-beam rails. Drill the holes at 24-inch intervals. Mount the frame and diamond plate to rails with carriage bolts, lock washers and nuts.

Wood Flatbed

Step 1

Fabricate one end and two sides of the steel channel frame on a flat surface. Fabricate the bulkhead and weld it at the front rail of the frame.

Step 2

Cut pieces of 1 1/2-inch lumber as decking that spans the length of the frame. Position the pieces in the frame. Fit the ends and outer edges of the decking into the steel channel. Weld the end piece of channel across the end of the frame.

Step 3

Position the flatbed atop the wood header rails on the truck. Align the sides and ends. Drill 1/4-inch pilot holes for 1/2-inch lag screws at 12-inch intervals along each rail. Make 1-inch diameter countersinks for the lag screw heads.