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Tue Dec 22, 2009 10:36 pm

LuckyMonkeyGarage wrote: Every time I view this thread I flinch at some of the creations! Sigh....... :roll:

Not one original looking roo bar has been made to date?

I think you have pointed out that you like the original design...and posted quite a few pics of them. I think we get it. What I don't see is your design or your effort to build anything.

I also see six years of talk and four designs built. I started reading this thread thinking I would step up and build something similar since I have recently become a bay owner and have the same safety concerns. After reading all this I want to commend those of you that put forth effort. I may still design and build my own but I will not try to do any sort of production. I was a certified welder for 15 years and I do 3D design now (ProE).

Here are my thoughts. I am not an engineer. The basic "roo bar" as shown is nothing more than an aesthetic contraption. I would like to see one subjected to a real world test but I know this will not happen. I have not torn into my 69 westy so I do not know exactly what kind of support it has up high (if any) but the way I see it is that the design depends on what your intended purpose is. For me, it is occupant protection...the bus is sacrificial. I can build another bus. Anything forward of the front axle is going to be part of the "crumple zone". To stiffen this area too much will possibly save the bus (to a degree) but then the forces are absorbed by the occupants...not good. But, that is the path I think I am looking down. To me, if I can spread the forces out to the a-pillars and the frame and direct the bus up over the object hit so that the impact is not just on the frontal sheetmetal then that would be a good thing. I understand the later buses have the "Y" pieces added to the frame to distribute the force but that's not enough.

So, the question is: How do I design and build something that will protect the passenger compartment (full cage?) that doesn't impede the design of the bus (I want to use my walkthrough), doesn't hurt more than it helps (either by trapping the occupants, crushing the legs, etc), doesn't look so hideous that I can't stand it and has a "weak link" to give way while absorbing the impact? Like I said, the bus is sacrificial. I agree, I don't want to total the bus in a 25mph crash either.

It seems to me that the lower mounts need to spread out along the frame (2 centered at the frame and 2 outer going further back diagonally?), run up in front of the bumper (maybe a diagonal angle like a skid plate to help push the bus over the obstruction?), only have one bend (multiple bends are illegal in race car chassis' for a reason), have a diagonal brace going back or a straight tube running through the sheetmetal to an inner tube structure?? and possibly tie in to either an inner tube between the dash and nose or to a spot higher on the a-pillar itself? Like I said, the bus is sacrificial.

These are just my initial thoughts. Any input appreciated.

Wed Dec 23, 2009 12:04 am

bugdust wrote: .
Anything forward of the front axle is going to be part of the "crumple zone". To stiffen this area too much will possibly save the bus (to a degree) but then the forces are absorbed by the occupants...not good. But, that is the path I think I am looking down. To me, if I can spread the forces out to the a-pillars and the frame and direct the bus up over the object hit so that the impact is not just on the frontal sheetmetal then that would be a good thing. I understand the later buses have the "Y" pieces added to the frame to distribute the force but that's not enough.

It seems to me that the lower mounts need to spread out along the frame (2 centered at the frame and 2 outer going further back diagonally?), run up in front of the bumper (maybe a diagonal angle like a skid plate to help push the bus over the obstruction?), only have one bend (multiple bends are illegal in race car chassis' for a reason), have a diagonal brace going back or a straight tube running through the sheetmetal to an inner tube structure?? and possibly tie in to either an inner tube between the dash and nose or to a spot higher on the a-pillar itself? Like I said, the bus is sacrificial.

These are just my initial thoughts. Any input appreciated.

I have had many of the same thoughts. My thoughts on saftery are this: any roo bar is likely better than none, as it spreads the impact over the nose, and I have seen some comments stating the dash is actually quite solid/structural/ the onoly piece of resistance north of the bumper. so a roo bar will make ahit that would have gone between the bumper and dash be spread into the two once the bar bends back into the body (anything over 5 mph i would fathom)
A bar made of .120 DOM or better is needed for safety concious designs, as that bar is cantilievered up there with a big sweeping 90deg bend. IT can't resist bending, simple fact. I very stongly thought about a down bar coming thru the front, then tied thru the floor to the frame. A bit akward, al ittle too close to your knees due to spacing, but doable. If I had a bay that was off road only I would do this. I also came up wit ha good cage plan, but that is a whole new thread.

the Y pieces are key. earlier bays are a joke up front. In a later bay take advantage of the fact there actually is something substantial up there. Affix a low bull bar that sticks out like a pouting lip, then tie it back into top of the bumper, which affixes to the end of the crumple zone, which affixes to the Y. Tubs are only meant to take loads along thier length, so align them towards the obstacle.

that is all I will say on the matter, as this is a thread for roo bars, not bay saftey, and I am wandering away from roos. If you are realy interested, copy and paste the posts and start a new one, no one likes a hyjacker

Fri Jan 01, 2010 7:52 pm

This is how the pieces are connected..
Slip them inside each end of the tubing, weld together, DONE.

Fri Jan 01, 2010 9:18 pm

fusername wrote:

that is all I will say on the matter, as this is a thread for roo bars, not bay saftey, and I am wandering away from roos. If you are realy interested, copy and paste the posts and start a new one, no one likes a hyjacker

Hi-jacker? I'd bet there are at least a dozen posts (if not more) in this very thread talking about bay safety and roo bars as impact protection. Like I said, design depends on intended use. If you just want something to "look cool" make yourself one out of some pvc pipe and be done. If you just want a copy of an original design to impress your friends because you have one like you saw in a brochure, buy or build one as shown. They are very simple and can be made up in a couple hours. Add a tire carrier to it if you like. If you want one that actually does something in the unfortunate event of an impact, then put some thought into it like I mentioned in my earlier post.

Sat Jan 02, 2010 10:26 pm

oh i meant as far as general bus front impact saftey goes. If you want to talk about roo-bars and their affect on it, and how they can be made better ,thats fine, but you will notice I started talking about caging and bull bars, different animals for a different thread. I wish I had time to sketch up my impact-resistant roos and cages and post em

Mon Jan 18, 2010 3:24 pm

In classified..

http://www.thesamba.com/vw/classifieds/detail.php?id=868269

Mon Feb 08, 2010 9:53 pm

Bought this bar off another TSer back this passed summer, a friend with some welding skillz :-) Fabricated a bracket under the bus. I spent a few hours cleaning it up tonight to get primed and painted up, I hope to eventually powdercoat it, but with Daytona Winterjam in a few days I really wanted to have it up and mounted before making my trans-eastern seaboard mecca to Daytona.

Wed Mar 31, 2010 7:45 am

Does anybody have a link to a pamphlet or add about the Roo-Bars? I think that would be neat to have at car shows to explain to people what the hell's on the from of my bus 8)

Fri Apr 23, 2010 12:39 pm

obnoxiousblue wrote: Bought this bar off another TSer back this passed summer, a friend with some welding skillz :-) Fabricated a bracket under the bus. I spent a few hours cleaning it up tonight to get primed and painted up, I hope to eventually powdercoat it, but with Daytona Winterjam in a few days I really wanted to have it up and mounted before making my trans-eastern seaboard mecca to Daytona.

Could you possibly post the tube diameter? I'd guess maybe 1-3/4". I'm going to fab my own and like these proportions.

Fri Apr 23, 2010 4:06 pm

all of mine are 1 1/2, a good size imho

Wed May 05, 2010 7:46 am

where can i get the corners and bent piping? like, do i haeve to bend them myself, or can i buy it bent then weld it myself?

Stuart

Wed May 05, 2010 10:43 am

You can buy muffler tubing all bent up from a bunch of placaes and weld it together yourself. thin stuff, but nice clean welds and you can get most any bend s you want. Or if you mean a complete kit I make and sell that myself.

Wed May 26, 2010 8:47 pm

Sat Aug 14, 2010 12:59 pm

this is cool

Sat Aug 14, 2010 2:15 pm

This bus just came up for sale over here... Nice bar.

Fri Sep 03, 2010 4:50 pm

Interesting, I always thought the rounded ends on the front roo bars went to the earlier models? Looks like both styles on one bus. Kinda cool.

Fri Sep 03, 2010 5:00 pm

Notice the original bottom mounts on this roo bar were cut and turned in, then they used some sort of strap to connect it to the bumper? Wonder if it was a quick fix when they were traveling around the world? I've always liked this bus:)

pheall wrote: this is cool

Fri Sep 03, 2010 5:30 pm

LuckyMonkeyGarage wrote: Notice the original bottom mounts on this roo bar were cut and turned in, then they used some sort of strap to connect it to the bumper? Wonder if it was a quick fix when they were traveling around the world? I've always liked this bus:)

pheall wrote: this is cool

Or as a way to get it closer to the body, note the mount next to the head light. It could be a way to make it shorter for shipping, might save 3-6", take the tire off and it is near stock length

Fri Sep 03, 2010 5:57 pm

I'm not sure if this contributes much, but if any of you have the funding to ship, I see free front and rear bars all the time on the aussie forums. They are a commodity item, and a lot of the time just get chucked out because no-one wants another one or they are too far away. Might be a good way to save some from the recyclers.

Fri Sep 03, 2010 6:05 pm

Sounds like you might be thinking more along the lines of a full roll cage baja bus? I think there might be forums for that. Also, redesigning a roo bar is not really my thing. I'm an old fuddy dud who likes old original stuff. I also like old original roo bars that are made like the originals even if they are a "aesthetic contraption". Seems like the original one I have from Australia is pretty damn strong though. For some crazy reason my thing is to keep vintage cars vintage.

Sorry to all of those that I may have offended with my keep it original talk. Believe it or not I do like custom designs, I just like it to look like it was from the time period the car is from. I also like good design that's well thought out too. :idea:

bugdust wrote: LuckyMonkeyGarage wrote: Every time I view this thread I flinch at some of the creations! Sigh....... :roll:

Not one original looking roo bar has been made to date?

I think you have pointed out that you like the original design...and posted quite a few pics of them. I think we get it. What I don't see is your design or your effort to build anything.

I also see six years of talk and four designs built. I started reading this thread thinking I would step up and build something similar since I have recently become a bay owner and have the same safety concerns. After reading all this I want to commend those of you that put forth effort. I may still design and build my own but I will not try to do any sort of production. I was a certified welder for 15 years and I do 3D design now (ProE).

Here are my thoughts. I am not an engineer. The basic "roo bar" as shown is nothing more than an aesthetic contraption. I would like to see one subjected to a real world test but I know this will not happen. I have not torn into my 69 westy so I do not know exactly what kind of support it has up high (if any) but the way I see it is that the design depends on what your intended purpose is. For me, it is occupant protection...the bus is sacrificial. I can build another bus. Anything forward of the front axle is going to be part of the "crumple zone". To stiffen this area too much will possibly save the bus (to a degree) but then the forces are absorbed by the occupants...not good. But, that is the path I think I am looking down. To me, if I can spread the forces out to the a-pillars and the frame and direct the bus up over the object hit so that the impact is not just on the frontal sheetmetal then that would be a good thing. I understand the later buses have the "Y" pieces added to the frame to distribute the force but that's not enough.

So, the question is: How do I design and build something that will protect the passenger compartment (full cage?) that doesn't impede the design of the bus (I want to use my walkthrough), doesn't hurt more than it helps (either by trapping the occupants, crushing the legs, etc), doesn't look so hideous that I can't stand it and has a "weak link" to give way while absorbing the impact? Like I said, the bus is sacrificial. I agree, I don't want to total the bus in a 25mph crash either.

It seems to me that the lower mounts need to spread out along the frame (2 centered at the frame and 2 outer going further back diagonally?), run up in front of the bumper (maybe a diagonal angle like a skid plate to help push the bus over the obstruction?), only have one bend (multiple bends are illegal in race car chassis' for a reason), have a diagonal brace going back or a straight tube running through the sheetmetal to an inner tube structure?? and possibly tie in to either an inner tube between the dash and nose or to a spot higher on the a-pillar itself? Like I said, the bus is sacrificial.

These are just my initial thoughts. Any input appreciated.