Thank you! If I decide to go this route I plan on trying to take the same level of care on this as I did for the interior. I appreciate your questions see my responses below.
1) This is something I still haven't gotten totally in the weeds on. Since lots of the design is similar to Aluminess I think I will need to investigate some more on how they do it and see if it would be possible to get enough strength out of that style pivot. In a previous bumper, I had built for my old Land Rover Discovery II I used a spindle style pivot
which I would think would be plenty strong. The only issues I see with this style are one how to integrate it into the bumper design while maintaining the light brush guards and two all spindles I have seen are steel so if I choose aluminum it wouldn't be an option.
2) I have looked at Ujoints bumpers and I like the idea of doing a steel subframe and then having an aluminum skin that bolts on as it would help give the main structure and swing arms a lot of strength. My biggest deterrent for this method is just how to integrate the brush bar connections into it all especially if those end up being steel because they're the swing arm attachments. I guess now that I am typing all this out the tail light brush bars might be adding more complexity than they are worth, but I do really like the look of them. I guess more to think about and look at.
3) If you know anything about CAD programs you will probably think this is really funny, but all of this along with all my interior work was modeled in Autodesk Revit. For those that don't get why that may be funny or odd, it's because it is an Architectural/Structural/MEP BIM software. I'll most likely end up doing the final work in Autodesk Inventor or Fusion 360, but since I use Revit daily for work I am more comfortable with the interface for coming up with my basic design.
4) Realitsacally probably not. I don't really plan on getting too crazy with it off-road, but there's always a chance that once you start down a trail you come across something bigger than you intended and only have one option of going forward. I've seen a few vans now that have had rear quarter panel damage from dropping off something and landing on the body, so I figured if I am going to design it from the ground up might as well try to address this. Also, I am not too proud to admit that some of these things are purely because I think it looks cool.
Thank you! I agree that always having some fuel on hand takes a little stress off when you are getting far out in the backcountry. Also having some additional storage/basket on top of the spare is a neat idea and something I'll have to play around with.
Thanks for the questions and comments!
1. I think the images are a bit deceiving in how far out the bumper would stick, but the plan was just to have the overall width match the width of the Bushwacker fender flares. In the model, I currently have some rub bars modeled, which I think is what you were circling. These were a last-minute addition. After adding a side ladder into my model I realized it would be a pretty big step up to the first rung of the ladder, so I figured adding one additional rung on the bumper might fix the problem while also allowing for some added protection. Once I put it on the passenger side I figured it would make sense to match it on the driver's side just for a more symmetrical look. This is just the first iteration of the design and I agree that it would be better to keep the bumper no wider than it needs to be to flow with the rest of the design.
2. Totally understand what you're pointing out here, and I think you make a good point. Here is an updated image that eliminates the flat spot, and just carries the same angle through to the end of the bumper.
Trying to think back at why I had it the way I did in the original design I think there were two reasons, though they may be flawed. I don't really want to hack up the body of the van unless I have to to accomplish the full wrap-around effect of the bumper, so that means I am trying to work around the existing drop of the body in the rear corner. When I initially tried to pull the line straight as you show I would have to level it out and drop it lower than I would really like at the rear end of the bumper, or I would need to cut the body at a higher plane but then there is the issue of the spring hangers. The rear spring hangers for the rear leaf packs hang down some off the frame, so if I cut the body up to give more room for the bumper the leaf hanger would now be lower than the bumper edge. So my compromise on this idea was what I have shown a flat section to keep the bumper from getting too low at the wheel well, but still allowing for a steeper angle return back to the face of the bumper. I should also state again that this hasn't left the model yet, so a lot of these things could change as I start dialing it in to more real world numbers and constraints.
I have looked at the Buckstop-Reunell bumpers and they seem like a very stout solid bumper, but for my preference, I am not as much of a fan of the overall styling. They do offer a lot of great options and it would be nice since they are so close by.
I think you bring up a great point and something that would need to be addressed in how the bumper would mount. If I did an integrated hitch then I would plan on having a mount that sits between the frame rails where the existing spare sits helping tie the bumper to the frame in a more solid fashion than the stock mounting holes as you mentioned. I also had thought about adding additional cross bracing from the frame to the bumper quarter panel extensions in hopes to eliminate any flexing of the bumper to the body, or pivoting off the end of the frame rails up and down. Thanks for pointing out some additional things I need to dive into more.