Builds Father, Son, and the Unholy UTE

[nukegoat]

I am def not a tube expert. Good luck and keep going

 

[Willys43]

Kelly, you may be able to put a gusset at the top corners after fitting the seats. Not as good as diagonals but better than tube only. Also you might want to use heavier tube wall on the outer hoop only.

 

[2fpower]

Kelly, you may be able to put a gusset at the top corners after fitting the seats. Not as good as diagonals but better than tube only. Also you might want to use heavier tube wall on the outer hoop only.

Got it! that makes a bunch of sense. Thanks Craig!

 

[TEQiddiot]

Interested to see how the sequoia rear hatch turns out. Sweet thread, subd.

 

[2fpower]

Interested to see how the sequoia rear hatch turns out. Sweet thread, subd.

Thanks, having a electric sliding rear window will be pretty cool I hope.

 

[half k cruiser]

Thanks, having a electric sliding rear window will be pretty cool I hope.

Not as cool as being a teenager and getting to drive that beast to school. Especially after you get to build it with your dad !

 

[noahfecks]

I was hoping that the guy who posted about his rollover would elaborate but what i think he meant was that a freestanding hoop without anything to keep it from moving forward or back in the cab wont do anything to keep your son safe. Remember that the bar can move in three planes during a crash. At a minimum I would tie it to the roof sheet metal all the way across.

Every bend you put in the tube is a pre-made failure point in the cage. You need to tie all four corners of the upper half of your proposed roll bar together with a gusset of some sort, the longer the better. Honestly you would be way better off to move the roll bar back from the seats and make a big x in the middle. What you have proposed will be enough to keep the cab from coming down in a single light roll but in a hard landing or multiple roll situation its going to crush down to the midpoint where your triangulation ends. You could use a smaller diameter tube for triangulation if it helps make it fit in behind the seats. Remember strength comes from shape more than from material

1 3/4" .120 tube is plenty for what you are doing, if you change your design you could get away with 1 1/2"

Hope that helps! I look forward to checking in on your progress every day, best thread on here right now, mega cool factor project for a father/son

 

[Mudder]

I should've been more clear, I wish I had put a gusset in between the top bar and the sides where the bend is to add strength to help keep it from side shifting in a roll over. As the bar going across the roll bar will only stop it to a point. Once that point is reached the roll bar will try and separate it's self from the bar going in between.

 

[LINUS]

K -

Here's a quick -n- dirty fab calculator I like to use as it lets you plug in real cro-moly vs. 'IDK, cheap hot formed tube' --- lets you see the strength or yield of quite different material from T-rated AL to SS & a few differing quality steel tubes:

Roll Cage Calculator- find the stress level in tubes or suspension parts!

I'm not the tube guy you referred to either, just a cert'ed welder (& a few other titles, and a few names I'm sure are used behind my back ). - IDK who the resident expert is.

@SmokingRocks might, he uses enough of materials & welder vocabulary he might know or be the guy, total guess.

 

[jeffro109]

If you are running the sides of the roll cage to the "A" pillar, you could create an "X" in the roof perhaps if there is room.

 

[LINUS]

How time to design the rollbar. The cardboard cut out is what I'm thinking the outer hoop will be. The question to the forum is:

1. what size DOM, I am thinking inch and three-quarter would look good, is that strong enough?

2. If I put in a lower bar and a middle bar at about the bottom of the window with two angled diagonal is that sufficient? See first pic.

3. At the bottom it looks like I can go back disgonally and attached at the frame. Is it a problem having the hoop bend in so much? See second picture.

Slee Short bus construction pic: http://www.sleeoffroad.com/technical/warwagon/images/web_publish/188.jpg

Looks like it didn't stop Christo & the guys.

You have to do it to make both the secure frame connection & then flare to pick up the body profile - and your triangulation sketch with the sub bar looks like it will keep it rigid if it gets flopped.
Again, not a cage guy or engineer though.

 

[SmokingRocks]

Triangulation / gusseting is key in designing a roll cage. I'm not an expert on cages but did help my old boss build a couple for his comp buggies.

Personally I have been designing a hybrid interior / exterior cage. It will have vertical supports at the A, B and C pillars with low mount gussets and triangulation bracing. Then the verts will penetrate the roof (May do a plate connection) after the verts are through the roof they will connect to a "halo" exterior horizontal bar.

Doing this will retain the interior head space, better protect the roof and A,B, C pillars. The design of the Halo will mimic a roof rack so it won't look ridiculous and will also be functional.

 

[2fpower]

If you are running the sides of the roll cage to the "A" pillar, you could create an "X" in the roof perhaps if there is room.

. First off, thank you very much for your post. I like this idea, however I am worried about in a rollover this Creating a blunt Object for head trauma. Been thinking about this comment all day, as it brings up the question what am I going to do underneath where the sunroof was for headliner. Maybe this would work if I somehow make the headliner to somehow on block it. My plan was to use the existing headliner rear area and cut that to fit the front. I could fiberglass the back to get it added strength. Anyone else have thoughts?

 

[2fpower]

K -

Here's a quick -n- dirty fab calculator I like to use as it lets you plug in real cro-moly vs. 'IDK, cheap hot formed tube' --- lets you see the strength or yield of quite different material from T-rated AL to SS & a few differing quality steel tubes:

Roll Cage Calculator- find the stress level in tubes or suspension parts!

I'm not the tube guy you referred to either, just a cert'ed welder (& a few other titles, and a few names I'm sure are used behind my back ). - IDK who the resident expert is.

@SmokingRocks might, he uses enough of materials & welder vocabulary he might know or be the guy, total guess.

thanks @LINUS . Great link. Also for the picture of slee's short bus Not sure if I've ever seen anyone with a short cab put a roll cage in. Will have to go back to my photo archive I built over the last four years

 

[2fpower]

I was hoping that the guy who posted about his rollover would elaborate but what i think he meant was that a freestanding hoop without anything to keep it from moving forward or back in the cab wont do anything to keep your son safe. Remember that the bar can move in three planes during a crash. At a minimum I would tie it to the roof sheet metal all the way across.

Every bend you put in the tube is a pre-made failure point in the cage. You need to tie all four corners of the upper half of your proposed roll bar together with a gusset of some sort, the longer the better. Honestly you would be way better off to move the roll bar back from the seats and make a big x in the middle. What you have proposed will be enough to keep the cab from coming down in a single light roll but in a hard landing or multiple roll situation its going to crush down to the midpoint where your triangulation ends. You could use a smaller diameter tube for triangulation if it helps make it fit in behind the seats. Remember strength comes from shape more than from material

1 3/4" .120 tube is plenty for what you are doing, if you change your design you could get away with 1 1/2"

Hope that helps! I look forward to checking in on your progress every day, best thread on here right now, mega cool factor project for a father/son

wow, I feel like hit the lottery with a lot of great information and comments today. You reminded me that on foo I put a 1 3/4 tube down the existing sides of the vehicle and put a 1 1/2 front cross piece above the windshield. Here's a picture of the tube going down the sides on foo.

Then how I covered it up, and made it look Purdy

Then here you should be able to see the tube running up by the windshield. As you definitely see rear of the sunroof opening foo also has a tube which is about where hoop will be on this build

 

[jeffro109]

^^^exactly what I was thinking, tuck the new tubes up into the existing body frame and cover it up with the headliner. Even a smaller diameter tube in the roof area is better than no tube in the roof area .

Take anything I suggest with lots of salt...I tend to overkill.

This is what I see mentally for tube, with green spots being good places for gussets. Then the upper corners taken up to the "B" and "A" pillars with any cross pieces in the roof you can get to fit. It's probably way too much if someone with real experience looks at it.

 

[woytovich]

I don't have ANY experience designing or building cages (but that won't stop me from expressing my opinion)

If you are going to build a cage build it to work or don't bother, because if you need it and it fails... Get advice from someone that knows about this stuff.

That said, I think the top hoop needs some triangulated support through the large empty space in the middle. I'm sure you can work out a plan that preserves some seat movement while providing protection that might in fact save your life. Function over form. Don't mess around with safety equipment.

 

[2fpower]

I was just explaining how I plan to extend the frame to another member and the overall theme fits this conversation. I plan to sleeve frame member, add new frame section and plate it. Overkill is the target when your son is the one driving.

 

[cjmoon]

are your plans to be able to role it over several times and it still holds form and doors still shut or role and keep you safe and it's tweaked and done/needs rework? both are safe methods look at how modern cars crush or 80 series pillars smash on rollovers. the norm 15 years ago was one diagonal across the main hoop. now everyone thinks they need rock bouncer cages. you have to determine the need for your build. remember deflection isn't always a bad thing it takes impact away from the occupants. That's why cars crush and are totaled easier today than in the past. the car dies to save the people that often walk away from tangles messes

 

[2fpower]

point taken. I would say, if this rolls, it is scrap metal. I would not expect doors to work. If I was going for that, I would build an exo-skeloton. I want to protect, but not go too crazy, as too much metal just gives you something to bounce your head off of, and get in the way.

going back to your comment @cjmoon would I be correct to say that the passenger area that we are talking about should not crush? My question is, typically everything up to the passenger area will crush taking the impact.