Hay wagon from an NH3 wagon gear

Hello all, been gone for about a decade or so. I'm getting back into doing hay again, and I've just started to collect equipment. I just bought 3 NH3 wagon gears, and I'm going to make them into hay wagons for small squares. I want to put 8x16's on at least the first two to see how they go. They're 10 ton gears with fifth wheel steering. I'm sure I'm not going to overload them. I have to extend them a bit, the axles have a 10' wheel base. What's the normal wheel base for a 16' bed? Am I correct in thinking that the front overhang is about a foot, and the rear is about 2'?
I'm going to remove the brackets and run 2 beams front to back, then run 2x8's perpendicular to the beams. I'd prefer running my floor boards front to back, but I want to save a little weight, and since the steering is fifth wheel, I need to have more clearance for turning. The wagons have 12.5L-15's on them, so that's just under 33" high. I'd like to keep the bed height at around 36" if possible, so that's the reason for running the floor boards perpendicular.
As for the beams, I'm thinking of using 3-2x10x16's laminated using construction adhesive and screws. I'm going to use treated lumber, anyone prefer fir or yellow pine? I hear fir might handle flexing better? I'm planning on having the beams 25" outside to outside as that will make mounting to the existing structure easy, and will give me room for the front wheels to swing without hitting unless I turn really tight. I also have to get a steel tube to extend the one connecting the axles as I don't think there enough there to extend it with enough in the ends to make it secure. I'm going to make sure the wood for the beams are dried out some and make a pass through the planer to get a nice surface for gluing, and make sure the top is planed flat to hold as little water as possible as they're going to sit outside. I'll use a preservative on the wood as well. I can adjust the axles wider as well, I'm thinking maybe 4" in from the sides of the wagon bed?
Anybody ever used this type of wagon gear for hay wagons? I'd appreciate your thoughts.

Make sure you put chains on each side going from beams to out side of turning axle to limit the amount of turn. Pa built a bale rack on an old wooden gear with a wooden tongue. When
we turned to short beam walked up over tire. When we straightened out it broke the tongue before it would pull the wheel back out of there because wheel is turning wrong way when
trying to come out. It just really did not work good for us.

Thanks Belgian, I was wondering how I was going to do that!! So simple a caveman could do it...

I hope you have very flat fields. Turn table type wagons upset really easy. When you turn in either direction the wheels move towards the center line of the wagon. Bolt both back rails to the rear of the wagon. You do not want much play as it will do the majority of the stabling of the load.

We had a couple of old horse wagons when I was young. They got upset on a fairly regular basis. Our ground has pretty good hills.

I know the Anhydrous wagons are cheap but there is a reason for it.

I've never used that style of running gear, but I make mine 8'x18' with PT 2"x10"s glued and screwed with plywood for the main beams (I used 2"x8"s in the one pictured, and they were a little light). I haul mine on the road with a pickup a lot, so I keep the rear wheels as close to the back of the wagon as possible to reduce sway.
I use larch for the rest of the wagon - 2x6 cross pieces and 2x4 uprights and 5/4x6 for the flooring. It's important to install flashing on the top of your main beams, and lay out your deck so that there isn't a space above them, to keep hay from building up on top of them
Pete

I think that you are going way over-kill. I use 3x8 stringers and 2x5 cross-members. I usually load 130 bales. You are putting your deck way too high in the air. Be sure to put aluminum flashing over the tops of your cross-members. You could also add spacers under the cross-members over the front axle pivot zone and make them not as high in the front so that you have more clearance. You never get anywhere near the load in the front as in the rear.

Thinking out lowd here. Is there a way you could hold the front of the rack up using only the center reach? Somehow hold your two stringers up without them running to the front
bolster? I just don't think your going to be able to turn wagon short enough for corners of field. That's the problem we had with ours.

I'm going to remove the tank brackets and clamp a couple of long 2x's to where I'd like to put them, and then I'll see what kind of turn radius I get. I can maybe notch out an inch and a half out of the beam possibly if I need a tighter radius. I'll post some pics tomorrow.

I really don't have a choice in how high the bed is, I can only go so low without welding up some expensive steel frame. I'm going to use treated wood and put sealer on after I let it dry down some, so I won't need flashing. I'd also rather over build it than under build it.

Most everything is relatively flat out here, that shouldn't be a problem. Most wagons around here are old and beat up, and they want too much money for them. I can move the wheels outward more for stability too.

So I got brackets off of one of the wagons today. I didn't get a chance to widen the wheel base as the bolts locking them in place are stuck pretty good. I'll probably have to use a little heat on them. But it looks like I'll be able to get at least a 45 degree turn from the front axle, which should be fine. I may not be able to track well in the corners, but I can always drop the wagon and just run the balers in the corners by itself to hit any windrow I miss.
I just realized that one of the wagons has the axles welded so they won't widen, but I may just make that a 8x14' bed since the wheels won't go out wider.
I still think I can get the bed height in at around 35-36", which I don't think will be bad.