Well, I got the frame of the wagon fitted, jig'ed and welded this weekend. First order of business was to get the drop axel figured out. I bought a old used beat go-cart frame off craigslist for $10 a while ago. Once I got it home I cut off the pieces I thought I might use at some point and pitched the rest. Two of the pieces I keep were 1" OD and had what looked to be the right bends.
After a little work I had the excess stuff cleaned up and cut it between each bend. Then took some measurements and did some cutting and a little more cleaning then got it welded together. I forgot to take very many pictures of this process but you can see the finished product down below.
So I figures I could use some old 2x4 scrap I had laying around and screw it to my "bike table" and create a temporary jig out of it. I think it turned out pretty good, the thing is pretty much dead nuts square. All coping/fish-mouths done with a hand file. You dont always need high end tools to get great results.
My welds are looking better after my little time off welding. It is crazy how a little time away and your welds start looking not that great again. They could still look a little nicer but I think they are pretty good for what it is for.
Frame all welded up, still need to do a few things like weld the mounting tabs for the tub, figure out the steering and weld up the hole that was left from the rear axel not being as big as the radius rods.
Side view to give you and idea, you also can see the wheels I am going with. The rear wheels I got off of my buddy Jimi's neighbor. He had a tool cart that he didn't want anymore and he gave me the roller for it free. I took what I wanted off of it and cut the rest of the frame up and will use that steel for future stuff I am sure. The front wheels came off a Schwinn tricycle. They are 10" and pneumatic so they should help the wagon roll smooth. The wheels were just placed there to help hold the wagon on end. It will sit a lot lower, ground clearance will be 4" in rear and 2" in front.