Having a mid-size pickup is just fine for one guy and a couple dogs. Things get interesting with three dogs, and downright cramped with two guys, three dogs, and camping gear.
Over the last year or so I've seen a few projects (Living With Birddogs and Idaho Upland Hunting) that inspired me to retrofit my existing topper to more easily accomodate dogs and gear. I knew I could build one with wood cheaply and easily, but aluminum offers many advantages and seemed like more of a challenge--I like to stay busy during the summer. Anyway, aluminum is cleaner, more durable, and just looks nice if you do it right. But I don't have a workshop in a steel building full of gnarly tools fit for cutting metal. I also don't know how to weld al-loo-min-ium, and hiring a welder would make any project cost-prohibitive. Without welds, joints would look too sloppy using common fasteners. And then I found these steel-core tubing connectors online. With that, this project was a go. After I finalized my design I ordered the connectors and some 1" aluminum tubing and a 4'x12'x0.063" sheet of aluminum from EMJ Metals here in Kansas City, and the doors came from Bob at Wingworks.
I cut the tubing with my Dad's miter saw and filed the burrs off the edges for a clean finish. The connectors fit very tightly with 1/16" wall tubing, once it's in it's not coming out. I used 1/20" wall tubing on pieces I wanted to be able to come apart--this thing is designed to be quickly disassembled.
Here's a look at the frame laid out before assembly.
I used an archaic drill press to put holes in the corner connectors for pull pins on one side and spring pins on the other side.
Then I set to work cutting the sheet with a circular saw and metal blade. It worked pretty well aside from the random chip that would fall into my shoe. It was too damn hot to wear proper work clothes anyway. I secured the vertical partition to aluminum angle that I mounted on the roof and floor and held all together with nuts and screws. I ran the calcs and it should support 500lbs with less than 1/2" deflection.
I used 0.063" polished diamond-plate for the back. Unlike the other two projects linked above, I decided to mount the doors inside the truck. I only have a 5' bed, so I decided to leave enough room for a water jug and vests in front of the doors. Otherwise the dogs take up most of the bed area with room for storage underneath them. I like the dogs to be able to load themselves, and I like the doors inside to keep the weather off them better.
Most of the time I'll only roll with one door and backplate installed. The other side will be utilized for storage. I figure I can fit my two setters and my buddy's setter together on one side, and then if we're carrying more dogs install the other backplate and door. I've got some plastic grating to add for floors and I plan to add a DC fan sometime, too. This weekend it gets it's first official test for the prairie chicken opener. I hope you like it as much as I do.