I have moved it back 50mm-2" off centre to change the ratio of the gap between the back of the tyre and the top just to get an idea of how much I need to lengthen the top by. This would mean an overall increase in length of 100mm-4". As you can see by the front guard, it has even more gap between the rear of the tyre compared to the top.
I used a profile gauge to see how much crown to wheel into the new top of the guard. Quite surprising as they actually look fairly flat. The crown gives it more strength and stops it looking like it belongs on a trailer! To match the roll at the front I passed it through the wheel with the soft upper to get the start of the roll.
The rest of the roll was completed by levering it over the pipe stake you can see in the background. If the sheet was wider to give more leverage, I could have done the whole fold over it. First time offering it up to the rest of the guard. This is without any hammer work at all. I am replacing the whole top section rather than just adding a narrow strip for the extra length. The reason is that the further away I have the two welds, the easier it is the control the distortion. Also it removes all the old cracks and previous repairs which all needed to be cut out and replaced as lots of fatigue and inconsistent shape.
Fully tig welded both ends on. Can really see how much longer it is now compared to the stock one. Can see also how that one has a twist it. Both had a lot of big dents and very twisted out of shape. I think the proportions are much more pleasing now. This is not the final position it will be fitted at but does show what it will look like once the rear suspension is at the final height. This is the stock mounting position for the guard. The rear suspension is sitting 50mm-2" higher though due to the lack of weight the bed has compared to the Grand Cherokee donor. I measured the compressed length of the coil before stripping the donor down. With these 190 lb constant rate springs means that over both of the coils it works out that there is 760 less pounds, 345 kg, than the wagon. Seems like a lot less but you have to remember that two rear doors and a hatch, rear seat, side windows, roof, and all the lining etc add up to a lot!
This is the stock mounting position for the guard. The rear suspension is sitting 50mm-2" higher though due to the lack of weight the bed has compared to the Grand Cherokee donor. I measured the compressed length of the coil before stripping the donor down. With these 190 lb constant rate springs means that over both of the coils it works out that there is 760 less pounds, 345 kg, than the wagon. Seems like a lot less but you have to remember that two rear doors and a hatch, rear seat, side windows, roof, and all the lining etc add up to a lot! Can see the rake it has right now is a bit much. Think the front and rear guards match a bit better now though and the bed sides don't look so plain now.
I wanted to get a better idea of close to final ride height. The centre coil is the stock Grand Cherokee donor one and had the rear sitting up 50mm-2" higher than stock due to so much less weight. On the right is a new Grand Cherokee SRT Eibach lowering coil that had it sitting 25mm-1" lower than stock. The only other spring I had on hand on the left was a stock rear coil spring from my KK Cherokee. Happened to have the same top and bottom coil size as the Grand Cherokee. When I fitted those it brought the back down to the stock donor height! Just have the guard balanced on a block but gives a better idea of how the guard shape sits over the tyre.
This still leaves just under 25mm-1" of rake which is how I usually set my vehicles up. That way with the offroad camper trailer hitched and load it will sit level. Been working out more of the dents in the radius. Found a modified tow ball and a steam pipe elbow made good dollies for the corners.
Also needed to address all the fatigue cracks where the skirts mount. Might be able to make out the line for the material I'm going to cut away. The area above the skirts was made longer to suit my deeper than stock bed sides. Also removed some of the crown where it meets the skirts to make it flow better.
What I also did was run the flange down into the cut away as the stock one on the right was way too thin there causing a stress riser and fatigue. I looked into making the skirt and step in one piece. Problem was it actually reduced the amount of material right at the fold where the guard meets it. Don't like the shape either.
Tried a narrower version but still not nice, so will make them more like the stock ones. Made the skirt up first as a separate piece.