The final cargo box components in finishing a restoration are the three hoops and the two lazybacks. The following is a dimensional description of these components for a late model WC-51/52. I cannot positively identify the wood used in my original pieces. I had to make two of the horizontal members for the bow hoops and the center longitudinal support member. The wood for the hoops appeared to be a hardwood, but not white oak as in the rest of the cargo box. I used red oak but ash could be another good choice. Finally, I would assume the lazybacks are made from white oak from the grain structure and since the dimensionality of these boards are similar to the cargo box boards.
The metal components (bow corners, toggles and straps) can still be found as NOS or reproductions. Figures 1-3 illustrate some of the final features of the bows and lazybacks. As always, the dimensions provided should be confirmed to ensure that they are self-consistent with your vehicle.
Figure 1. Overall view of a lazyback and hoops.
Figure 2. Close-up of exterior end configuration of the lazyback.
Figure 3. Close-up of interior configuration of the lazyback.
There are three wood components of the bows on the WC.
1. Vertical uprights
Cross-section: 1.7" x 1.2"
2. Horizontal cross members
Cross-section: 1.7" x 1.2"
3. Center support member
Cross-section: 2" x 1"
There are 6 metal corner bows which connect the uprights to the cross member forming the bow. I have read of other cross-sectional dimensions such as 1.75" by 1.25" for these wood components but my original pieces measured 1.7" by 1.2". Whatever dimensions are used is fine as long as they fit into the corner bows once primed and painted. I found it best to mark the hole locations for the corner bow fasteners with a corner bow and use a drill press to ensure perpendicular holes for the required 5/16" pan head bolts. 24 bolts are used altogether and these bolts are available through Fastenal.
The vertical uprights have a toggle bracket on one end which locks into six bed pockets. This bracket is attached to the upright with a 1/4" carriage bolt 2.25" from the end of the upright which connects to the cargo bed.
The rear two vertical uprights have a cast eyebolt mounted 20.5" from the bottom end. The threads for the tee nut and eyebolt are 3/8"-fine. As usual, the bolt hole is to be counter-bored for the body of the tee nut so that the wood does not split.
The three bows are connected with a center support member and three brackets. The original bracket dimensions are shown in Figure 4. I had to make my center support member so I made the cross-section dimension as large as possible to minimize any racking.
The horizontal cross members each have three counter-bored holes centered on the top surface for carriage bolts to mount the bracket shown in Figure 4. The counter-bore depth is sufficient to recess the carriage bolt head in the wood. This allows the heads not to protrude beyond the wood surface. The center bolt goes through the horizontal cross member through the center support member and through the bracket. This bolt is 5/16" and the fastener is a wing nut with a lock washer. Two smaller 1/4" carriage bolts are along side the center one to attach the bracket to the horizontal cross member. Lock washers and hex nuts are used in this case.
The bows are also shaped to allow the water to drain off. Steam forming them is the traditional approach but soaking them in water for a couple of weeks worked well for me. This was accomplished by making a tubular container from a large diameter PVC pipe with one end sealed. After soaking, I clamped two of the horizontal members together at the ends with a 2" spacer at the center. The wood was unclamped once thoroughly dried. The final height difference between the center and ends should be about .75" after some spring back.
Figure 4. Illustration of the bracket for the center support member.
The lazybacks each consists of two 3/4" thick boards 70 1/2" long. There are two metal connecting brackets which are attached to the cargo box with 3/8" diameter pins. These brackets are fastened with 1/4" counter-sunk, flat head screws. Their washers and nuts are recessed from the interior side by 13/16" counter-bored holes. These brackets are 15" in length and 5/16" thick with the sharp edges at the end slightly beveled. Figure 5 illustrates these brackets and hole spacing.
The two boards have another metal strap at each end to which a chain from the cargo box is connected. The hole which the chain is connected through is 1/2". The strap is again 3/16" thick and 1 1/8" wide. The portion which extends into the notched region of the upper lazyback is bent inward at approximately 30 degrees. Again, the fasteners are 1/4", counter-sunk, flat head screws with washers and nuts recessed in 13/16" counter-bored holes.
The final component of the lazyback is the vertical member shown in Figure 6. The edges of the beveled wood surface are rounded to eliminate any sharp edges or corners. This component fixes the lazyback in the vertical orientation. A 1/4" step bolt is used to permanently attach this component to the cargo box. The other end is fastened to the upper lazyback board with a 3/8" step bolt and wing nut. Three are required for each side and the 3/16" thick metal tongue is oriented so that the opening is to the rear. Two wood screws are used to attach the curved metal protector (guard) to the bottom end of the bracket.
Figure 5. Illustration of the left side lazyback from the interior side.
Figure 6. Illustration of the vertical upright for the lazyback.