Cherokee exo..
- Thread starter BIGdaddy
- Start date
BIGdaddy
Expedition Leader
good idea. they'd think it's weird that I'm not on 40's though..haha...
SWbySWesty
Fauxverland Extraodinaire
I keep going back and forth on exo vs inside...will watch this thread. While I've seen some cool exos (here's a pic) I'm leaning towards an inside cage...
BIGdaddy
Expedition Leader
what do you all think of using a product like these...
To tie into the drip rails for strength..?
I'm not planning on having any interior bars at the A or B pillar. This is a major issue due to the lack of triangulation gained by having a diagonal brace behind the front seats, but I'm not willing to put tube anywhere but behind the rear seat,
At the C-pillar, I'd like something like this w/ headrests and something other than expanded metal as a material(removable for cargo storage):
imagine that the sides of this are bolted through the JCR panels, and tied in close to both the C and the D pillars.
To tie into the drip rails for strength..?
I'm not planning on having any interior bars at the A or B pillar. This is a major issue due to the lack of triangulation gained by having a diagonal brace behind the front seats, but I'm not willing to put tube anywhere but behind the rear seat,
At the C-pillar, I'd like something like this w/ headrests and something other than expanded metal as a material(removable for cargo storage):
imagine that the sides of this are bolted through the JCR panels, and tied in close to both the C and the D pillars.
SWbySWesty
Fauxverland Extraodinaire
what do you all think of using a product like these...
To tie into the drip rails for strength..?
Those are what my JCR roofrack uses to attach...4 to be specific. That reminds me, someone asked for photos over on my build thread...gotta remember!
BIGdaddy
Expedition Leader
I'm thinking you could mount something like these over the rear window, using the exo as a substrate:
....to keep the weight low and with them locked, with the locking mounts that Wil now sells, they'd be a good deterrant to theft
Front of load area-cargo barrier
Sides of load area - 2 locked rotopax fluid containers
Rear of load area - hardened rear hatch (metal grill over rear glass?)
....to keep the weight low and with them locked, with the locking mounts that Wil now sells, they'd be a good deterrant to theft
Front of load area-cargo barrier
Sides of load area - 2 locked rotopax fluid containers
Rear of load area - hardened rear hatch (metal grill over rear glass?)
Root Moose
Expedition Leader
Another hit-n-run post...
Some of this will be repetitive to our past discussions...
- Put a roll hoop inside the vehicle behind the rear bench (C-pillar). Make sure occupant heads can't hit this hoop in a whiplash situation. Consider adding rear head rests.
- Put a halo on the outside that attaches through the roof and goes forward to the A-pillar area.
- Run A-pillar supports down the A-pillars on the exterior, through the top of the fender; somehow weld/bolt to the front bulkhead and/or front unirail. I can't visual the structure there right now for some reason - try to incorporate some kind of a "butterfly" stiffening assembly in this area similar to what is used on a race prepped Miata or S2000.
- Also add a hoop at the D-pillar, complete the roof structure support at this area.
- I'm not a fan of the D110 style external cage. I understand why it is done that way but I see it as something to get snagged on trees. I'm also more for clean visual design. The D110 setup looks like a kludge caused by safety regulation changes as far as I'm concerned. I'll let a LR zealot correct me.
- It wouldn't hurt to use those clamps in the B-pillar area. I don't have much faith in the gutters though. The drip rail is just a pressed on thing where the side and roof panels are welded together. Or you could do internal down tubes inside the body. Given a choice between the two I'd lean to the former. Internal tubes anywhere near a skull with no helmet are a bad idea IMO.
- I wouldn't stress too much about lateral triangulation in the interior roll hoops. The practicality of this structure will not allow good triangulation anyway. You can't triangulate the windshield area obviously.
- The purpose of this structure is to help in addition to the existing unibody sheet metal. I'd hazard a guess this would be at least twice as strong as the existing roof. Probably more.
- I need to think about this more, but my inclination would be to have the C-pillar hoop leaned backward at a say 70* angle, the D-pillar forward the say angle so they meet to make a triangle in the side view. Close the triangle with some horizontal tube at the bottom. Additionally brace laterally through the area under the floor and/or under the bench to stiffen the base points. Attach the roof structure at the top. Massively strong over the little ones in the rear bench.
I dunno. Shoot these free formed ideas down.
Some of this will be repetitive to our past discussions...
- Put a roll hoop inside the vehicle behind the rear bench (C-pillar). Make sure occupant heads can't hit this hoop in a whiplash situation. Consider adding rear head rests.
- Put a halo on the outside that attaches through the roof and goes forward to the A-pillar area.
- Run A-pillar supports down the A-pillars on the exterior, through the top of the fender; somehow weld/bolt to the front bulkhead and/or front unirail. I can't visual the structure there right now for some reason - try to incorporate some kind of a "butterfly" stiffening assembly in this area similar to what is used on a race prepped Miata or S2000.
- Also add a hoop at the D-pillar, complete the roof structure support at this area.
- I'm not a fan of the D110 style external cage. I understand why it is done that way but I see it as something to get snagged on trees. I'm also more for clean visual design. The D110 setup looks like a kludge caused by safety regulation changes as far as I'm concerned. I'll let a LR zealot correct me.
- It wouldn't hurt to use those clamps in the B-pillar area. I don't have much faith in the gutters though. The drip rail is just a pressed on thing where the side and roof panels are welded together. Or you could do internal down tubes inside the body. Given a choice between the two I'd lean to the former. Internal tubes anywhere near a skull with no helmet are a bad idea IMO.
- I wouldn't stress too much about lateral triangulation in the interior roll hoops. The practicality of this structure will not allow good triangulation anyway. You can't triangulate the windshield area obviously.
- The purpose of this structure is to help in addition to the existing unibody sheet metal. I'd hazard a guess this would be at least twice as strong as the existing roof. Probably more.
- I need to think about this more, but my inclination would be to have the C-pillar hoop leaned backward at a say 70* angle, the D-pillar forward the say angle so they meet to make a triangle in the side view. Close the triangle with some horizontal tube at the bottom. Additionally brace laterally through the area under the floor and/or under the bench to stiffen the base points. Attach the roof structure at the top. Massively strong over the little ones in the rear bench.
I dunno. Shoot these free formed ideas down.
Root Moose
Expedition Leader
I think you are on the right track to incorporate these design elements.
I have seen A-pillar stuff done that is tighter and much less obvious. I want to say at the Advanced section of NAXJA but I'm afraid to send you on a wild goose chase.
I'm not certain I would bring the outside bars out as far as shown on the red XJ. I just don't see the need for the way I'd use my Jeep. I'd focus more on weight carrying, roll over structure and then looks. I'd be inclined to make the front of the halo match the upper arc of the top of the windshield too.
This raises another issue. I'd make the external part of the cage bolt on/off. One of the things that has always bothered me about internal or external cages is the clearances required to change out the windshield. Some guys make them as if you'd never have to do maintenance again. I'm not interested in using a sawzall and welded when changing a windshield. If you make the A-pillar section bolt to a butterfly brace section like I suggest above, and have it bolt through he roof at the rear then the whole assembly can be removed to perform maintenance on the vehicle (changing windshield, repainting, whatever).
I'm really not a fan of that expanded steel bulkhead above. I'd also be inclined to lean the bulkhead back to behind the seat belt top bolts. I might be be keen on the structure with that kind of clearance. Hard to say.
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Root Moose
Expedition Leader
Btw, those A-pillar bars will likely eat an easy 2-4 mpg regardless of how they are done or how the rest of the vehicle is built. They are sited at the worst possible place for efficiency. The root of the windshield is a high pressure area that bleeds around the sides at the A-pillar and then you put these ~4" high walls to double amplify the pressure gain.
Not much you can do about it. Just mention for the sake of completeness.
Not much you can do about it. Just mention for the sake of completeness.
BIGdaddy
Expedition Leader
Another hit-n-run post...
Some of this will be repetitive to our past discussions...
- Put a roll hoop inside the vehicle behind the rear bench (C-pillar). Make sure occupant heads can't hit this hoop in a whiplash situation. Consider adding rear head rests.
- Put a halo on the outside that attaches through the roof and goes forward to the A-pillar area.
- Run A-pillar supports down the A-pillars on the exterior, through the top of the fender; somehow weld/bolt to the front bulkhead and/or front unirail. I can't visual the structure there right now for some reason - try to incorporate some kind of a "butterfly" stiffening assembly in this area similar to what is used on a race prepped Miata or S2000.
- Also add a hoop at the D-pillar, complete the roof structure support at this area.
- I'm not a fan of the D110 style external cage. I understand why it is done that way but I see it as something to get snagged on trees. I'm also more for clean visual design. The D110 setup looks like a kludge caused by safety regulation changes as far as I'm concerned. I'll let a LR zealot correct me.
- It wouldn't hurt to use those clamps in the B-pillar area. I don't have much faith in the gutters though. The drip rail is just a pressed on thing where the side and roof panels are welded together. Or you could do internal down tubes inside the body. Given a choice between the two I'd lean to the former. Internal tubes anywhere near a skull with no helmet are a bad idea IMO.
- I wouldn't stress too much about lateral triangulation in the interior roll hoops. The practicality of this structure will not allow good triangulation anyway. You can't triangulate the windshield area obviously.
- The purpose of this structure is to help in addition to the existing unibody sheet metal. I'd hazard a guess this would be at least twice as strong as the existing roof. Probably more.
- I need to think about this more, but my inclination would be to have the C-pillar hoop leaned backward at a say 70* angle, the D-pillar forward the say angle so they meet to make a triangle in the side view. Close the triangle with some horizontal tube at the bottom. Additionally brace laterally through the area under the floor and/or under the bench to stiffen the base points. Attach the roof structure at the top. Massively strong over the little ones in the rear bench.
I dunno. Shoot these free formed ideas down.
These are good thoughts. My fabricator buddy has similar thoughts...that you'd simply have to be ok with the mpg loss, as well as the fact that without internal triangulation behind the front seats, its not going to be as strong as it possibly can.
We talked about intended uses,though, and he said that in a gentle flop against a hillside,etc...that this would be very durable. In a multi-roll off a shelf road, you're pretty much going to be sacrificing the vehicle, and every little bit helps.
The mpg drop from the a-pillar is a good point. I think I keep forgetting that...haha..
He was sayin' that he liked the use of the JCR panels, cuz most of his time is spent on attachment points. So if he's got strong, easy points to attach to, then my cost will mostly be materials, time to bend tube, and then time to weld up the nodes.
I like the side view triangulation idea. I agree that if the C-pillar is strong both front to back(c to d pillar) and side to side (pass to driver via bracing) I wonder how much strength it would give the A-pillars as they try to rack backwards from having the weight of the truck press on them in a roll.
Where I think this plan gets defeated is if a rock were to hit between the A pillar and the C pillar. There's no transfer of load there...it would just bow inward like a drinking straw until it hit the sheetmetal of the roof and began buckling at the b-pillar.
Maybe this is ok, though. I've seen a lot of crumpled xj's and it seems like the majority of them are crushed the most severly at the A-pillar and that the severity of the deformity is diminished as you go back towards the rear of the car.