I finally decided to start making a tailgate lid for storage that I've been wanting for a while now. Had the main idea of what I wanted; two doors, locking latches, and all the other usual jazz. So about a week ago I started measuring the tailgate panel and got started on a CAD drawing/model that I could print out at full scale to determine if things were lining up before I decided to take it to the water jet. I took a vertical picture of the tailgate with a ruler for scale and used it for a reference sketch in Solidworks to get everything going.
You can see the dirt that got into the tailgate under the carpet panel because of the dent in the tailgate surface. I decided to make the bottom extend further down than most tailgate lids offered by vendors, but not too far to interfere with the proper sealing of the bottom weatherstripping.
I went through about 4 paper templates for the doors and main panel. Surprisingly, making a .DXF and full size printing on multiple A4 sheets worked very well and gave final dimensions that were less than a 1/16" off of the end-to-end horizontal dimension. After that was all set, I took the files and material to be water jetted out. It helps when you get to use these kinda fancy tools at free at school. The top panel is .135" steel plate and the doors are black 1/2" Seaboard HDPE.
After everything was cut, I got started welding a lip around the inner door perimeter to act as a stiffer, as well as an vertical extended piece to mount the door hinges and door stops on the opposite side.
I had a couple ideas on how to bend the flat bar into the radius that I needed. I made it a standard bend die radius that machine shops could bend, but all the ones around me were all wanting too much for what I thought I knew I could accomplish with a MAP gas torch, a few heavy tacks, and an adjustable wrench. So, I went to town and it ultimately came out really nice. I purposefully lined the flat bar up a little bit shy of the panel perimeter to account for welding and grinding later on.
Here is the first side all finished up.
I started with the second lip on the inner edge in the middle and worked my way to the left side edge so that I would be a little easier to determine the length to cut at the end. Turned out being a much better idea since it went much quicker and easier.
I got a little better bending the radii on the second go round (right). I ended up correcting the semi-irregular bend on the left by heating and giving a couple good smacks with the big ole hammer. All these tacks were ground down so what they could be welded over later without causing a larger portion on the weld that might interfere with the cut of the actual tailgate later down the line.
Kinda looks like someone who had an idea of what they were doing did it
My idea was to stitch weld the flat par all the way around on the bottom side, then weld the .135" panel to the flat bar on the inner edge so I could grind all that off to make it basically looked like one piece of metal. I don't really think that was necessary since it didn't really add much strength, but was mostly for cosmetics and to make sure the powder coat didn't crack around there after some use.
Here's a mockup of the door size to the panel. Went with a 2mm offset from the inner panel door dimension which turned out being pretty much perfect to ensure nothing binds when opening or closing. The initial height for the doors was incorrect because of the hinge not being the correct dimension in the Solidworks assembly I had. Wasn't a problem though, I just ended up taking about 1.5mm off the top with a straight router bit.
in' hole and hoping for the best, but that is future me's problem
