The bed rack is actually really simple, but were I to do it again, I'd use something thinner as, while strong, it was stupid heavy (all 0.25" 2x4 square tube cut and welded together and then attached to 0.125" angle iron). I ended up drilling holes into the inside of the bed and just bolting it on with some grade 8 bolts and washers.
I built it by making the hoops to match the roofline (one at each end...at this point I found out that the bed is a different width in the back compared to the front, but was too far into it to change it). Then I just put a long beam front to back with a couple of cross beams in between.
This was my main tool for cutting and how I got everything lined up to be even...it's sketchy but it worked (this was back when we just got the shop built, so it's nice and empty)
It was level enough to support the heavy beam without moving, so it worked.
I would definitely recommend one of these band saws...it makes nice clean cuts really easily and really helped in getting everything on the correct angles.
After the first few cuts, I went and measured again...
and again and again until I had a mini mockup to make sure I was on the right path.
From there, I knew I had the angles right and made my first hoop...then test fit it on the MJ to make sure it matched the roofline (I had some help holding it up while I stepped back to eyeball it)
I tacked the first hoop onto angle iron that I cut to length for the bed rails. Then, I made another identical hoop for the back. The back of the bed is narrower than the front of the bed but it was close enough that I just went with it (and was short on time before a trip that needed this done for).
After that, it was simple. I measured and cut some north/south beams to connect the hoops:
Then measured and cut some east/west beams to add to the structure:
I welded it all up as best as I could and jumped on it a while to make sure it wouldn't fall apart. Then set out on the trip...I ran out of time to paint it so it gathered a bit of surface rust as I went but it worked. Since I built it all on the truck, I didn't realize how heavy it was until I had to take it off. It takes three strong adults all of their strength to get it on and off the truck and easily weighs 400+ lbs. Definitely overkill, but it looked great. I do want to make it again, but use thinner steel next time (and correct the rear hoop width).
From my notes when I built it: (I may have had to invert some of the numbers when I went to the saw (180-x)...I can't remember now, but when you do it, it'll be obvious to you)
Each leg I cut:
- Bottom of leg at ~17 degrees
- Top of leg at ~36 degrees
- Outside length of the leg was 21" long (top to bottom)
For the angle iron:
- Bed Ledge is approx 1" wide
- Length of ledge is 89-90"
- Length of inside bed is 87.5 (got to cut some room on the inner side of the angle iron so it fits around the front of the bed and the tailgate stop at the back)
Top beam for the hoop is
- 48.5" / 45.5" lengths (top/bottom)
- Cut top at angle of ~37 degrees