Cage design

[1-MEAN-X]

I was being productive at work today and designed this cage for my '01sport. Now it will be a long way off before I get around to building it, but I was kind of proud and wanted some input. It isn't dimensioned correctly around anything, but it should be in the ballpark.

 

[1-MEAN-X]

This design was inspired by this RC crawler.

 

[rookieshooter]

I'd rather have the B pillar vertical then the dog leg if you could. Any bends in the A or B pillars weaken it. You can't really get around it on the A cause of the window. The dog leg will act as a crunch zone.
But I do see where it is doubled in the B. I guess cause of the dog leg.
Used to be in some racing sanctions you had to run the B straight down.

 

[1-MEAN-X]

I thought that too, but I saw a tube buggy build on extreme 4x4 that was supplied by essentially off road that had slanted B pillars also that were doubled up and they were confident in the strength of the design.

 

[james t]

It looks really good. Couple of issues-

1- What rookieshooter is refering to is the bend in your B pillar(s). Notice the buggy has the B slanted, but not bent. Yours would probably be fine since it's doubled up, but it would be alot stronger if it didnt have that bend.

2- There's an X over the rear area (B to C) but nothing over the front (A to B). A good way to do it would be an X over the entire roof... it'll look like a V from A to B then a ^ from B to C.

3- Once you start actually building a cage inside a fully roofed explorer you will throw away any plans you have written down on paper. LOL. Trust me i went through the same process.

 

[1-MEAN-X]

Round 2: I added the "X" above the driver as well as sloped the "B" pillar instead of bending it. I also added a triangulated cross bar behind it for more support. If I do in fact get around to building this, I think it would be with no roof. This would be a chop top cage. Leave the windshield and have doors, but that's about it. Getting to those top welds would not be something I would want to deal with.

 

[snoranger]

You'll want to change up the stubby bars attaching B1 to B2 (for lack of a better term.), you want one to land inline with the bars running to the back. You always want to land a bar at an intersect point, not in the middle of a run, its stronger that way.

 

[1-MEAN-X]

 

[rookieshooter]

Much better on the B pillar and the way you did all the new triangulated pieces.
I'd make sure that you tie some. if not all the vertical to the frame by way of sandwiching the sheet metal floor between two plates, one top and one bottom unless you cut a hole large enough for the tube. The ones coming off the frame will be most likely angled off the side of the frame.
Also if you really plan to do a top notch job, I would build a tube frame for the seats to bolt to. This is how I did my cage. Not good to have the cage shift with the seats bolted to frame

 

[james t]

Looks beef.

The welds and dealing with the roof is a PITA. Most folks go through the floor with a hole saw, tack the cage then lower down through the floor so you can get to the top and finish weld. I did similar to this on mine but i simply cut an "L" in the floor under each tube and bent the floor down. When all was finished i hammered the floor back up and welded it.

 

[Rick]

I would like to see a dash bar and a bar tying the B-pillars together for strength and a shoulder harness mount.

 

[Bruces expo]

Nice Start ! , But I'm With Rick On The Dash Bar And a Bar Tying The B Pillars Together , Still Very Nice Plans And Drawn Out , Looking Forward To Seeing More Progress !!

 

[offroadkc]

The A pillar bar would be easier if you did it in 2 pcs that start at the btm and go up to the B pillar. That compound bend would be difficult. Then you do the brow bar, dash bar, harness bar (I agree with Rick) to tie it all in and finish it off.

 

[1-MEAN-X]

I agree it would be tough to get that bend if it wasn't done in CAD. The nice thing now is as long as I can orient my mind correctly I can take simple angle measurements from the CAD program in relation to each other.

 

[jmdirk]

+1 on Rick's comments. You could greatly improve the roll-over strength by tying together the A pillar with a dash bar and the B pillar with a cross bar for a shoulder strap. Probably would want to consider putting an X in there while you're at it as well as the C pillar area.

An X structure is going to be a lot stronger than parallel members. A box or rectangle structure easily deforms into a parallelogram when pushed from the side without changing the lengths of any of the members. By putting an X in the box, it can no longer deform without compressing one of the X members and stretching the other.

I'd also gusset areas where it's impractical to put in X/triangles

 

[1freaky1]

Definitely looks good and yes I have to agree on the last few upgrade comments for strength, Nice job drawing it out!

 

[1-MEAN-X]

Crap. Sorry I made those changes a few days ago and thought I already posted them.

 

[snoranger]

Most off-road rollovers are to the side. You want as much side protection as possible. A good way to add side strength without sacrificing rear vision would be to add kicker bars from where B and the B spreader bar (shoulder harness cross bar) meet, down the the frame.

A stronger way, but one that would render the rear seats useless and block some of your vision, would be to X the B pillars side to side.

 

[Dannyboy]

If I were to do a cage again, I would pull my windshield again & then cut off the roof at a,b,c &d pillars (4door) build the cage and weld the roof back on.

 

[james t]

If I were to do a cage again, I would pull my windshield again & then cut off the roof at a,b,c &d pillars (4door) build the cage and weld the roof back on.

Yes x1000.