Collision safety in our cars

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oprn
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Re: Collision safety in our cars

Post by oprn »

For sure the roof and supporting structure down the sides where a single roll loop would normally be is way overbuilt. The front of the car is completely neglected as far as integrating it into the added structure. I do like the side protection though and that to me is more important than the roof.
Ol'fogasaurus
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Re: Collision safety in our cars

Post by Ol'fogasaurus »

Without knowing more about the materials used, especially the tubing, its dia., material thickness, is the tube seamed or not, the temper, etc. and other things I see a lot of potential weakness including the dia. and joins to it. Those "X" joins" especially with the small gaps between the joins and a bunch of other things. I keep going to the pictures and looking at them and seeing more and more each time.

My jobs in "engineering" got me going on things like this.

Lee
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oprn
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Re: Collision safety in our cars

Post by oprn »

I think this cage is a case of someone substituting volume of material for a proper thought process. While I do think it affords an improvement in protection, is it useful protection and is it protection from the most vulnerable angles?

The statistics I looked up tell me the breakdown goes like this: 60% frontal, 25% side impact and 3% roll over. My previous experience in the collision repair industry would confirm that to be pretty close. This cage design in question in my view (without knowing the material composition etc.) appears to put about the right emphasis on the side collision but has the frontal and roll over completely a$$ backwards.

My whole point in this thread is that historically we as street Buggy builders put all of the emphasis in the wrong place when building additional crash protection. We by default follow the off road guys who are driving in a completely different world with completely different risk factors.

I am not saying I have a solution, I am just saying... let's take a step back and consider our specific risks and give it some serious thought. By the way, when you think about it the sand rail crowd do side protection. What can us glass Buggy guys learn from them? I am also not saying that roll over protection is a bad idea just that maybe other forms of protection are more important and should be given a lot more thought.
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Re: Collision safety in our cars

Post by Ol'fogasaurus »

https://www.thesamba.com/vw/gallery/pix/2491868.jpg
https://www.thesamba.com/vw/gallery/pix/2491867.jpg

For the street, people have always gone too soft with a hoop (especially) or a cage. What is needed off-road might be a bit stronger but getting involved in a wreck of any kind on the street can be just as bad if not worse. I've seen a couple of "Wads" in the junk yard before especially when rails were allowed on the street but with glass buggies also.

A glass body is not much strength wise, and it has no top for load transfer... it just looks cool. The VW pan needs a lot of strength added to it for most any use once the body is gone. Loading transfer is needed in say a rear ending or roll over. The same for a side hit. The cage, when done right, can transfer some of the front to rear and side to side loading.

The cage setup shown might be set too high for side hits and the rear hoop should be in contact with at least the upper tube and... getting in and out in a hurry looks a bit difficult.

The same for a front and rear Smack-a-Roony. Not sure of the material on the home-made pan but the bend is too sharp for the load transfer that may be needed. The floor needs some beading to stop flexing unless the material is pretty thick but even then ....

Again, each time I look at it I see more things I would question if I was still working.

Lee
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oprn
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Re: Collision safety in our cars

Post by oprn »

Most cages I have seen built for glass Buggies have 4 long vertical uprights with little to no fore/aft bracing. Those long vertical members would fold easily in any front, rear or side collision. Even in the rare event of an actual roll over they would fold sideways quickly without diagonal bracing.
Last edited by oprn on Fri Jun 07, 2024 9:21 am, edited 2 times in total.
Ol'fogasaurus
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Re: Collision safety in our cars

Post by Ol'fogasaurus »

Very true.
cagesamplesW[1].jpg
I've posted this before. Even my blue buggy's cage is not complete as it should be, and it was built by someone who knew better.
600x450.jpg
Missing is the side bars in-case of being hit that way. My Honda Pilot has been hit in the front end like that several times. Head to head and rear end hits seem to be less on the sand but the T-bones are more common.

This was taken before the non-commercial body lift was built. A commercial front piece in good shape was found but in my black buggy I did make the Napoleon's hat as well as the sides and rear pieces out of heavier duty metal.

In the street things change a lot. More head on and tail hit compacts.

Lee
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oprn
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Re: Collision safety in our cars

Post by oprn »

Another thing I see often is the cages/roll bars just bolted to the pan. That is just single layer sheet metal guys! It will rip out/punch through like the lid on a sardine can!
Ol'fogasaurus
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Re: Collision safety in our cars

Post by Ol'fogasaurus »

That is true but then there is the problem with the body mount setup which is where I am having problems with my black buggy.

The body is not like a buggy with the mounting flange and attached to it on the outside of it and going straight up to the curved part of the body, my black buggy has an upper strengthening flange that curls in and blocks the cage from mounting to the pan flange. In the rear, if I attach to the floor (necessity) then I have to custom bend the flange to also connect to the body mount flange and the body lift. Add to that the floors are not flat and there are the stiffening beads on the floor.
buggy4.jpg
buggy7.jpg
Also, since I am running a V6, tied to a bus trans and the fuel tank is also in the rear things got complicated. Add to that protecting the shock tower's upper shock mounts I decided to try something else besides using the commercial protecters that would have to deal with the additional weight in the rear.

"Cause and effect" are really an everyday thing.

Lee
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oprn
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Re: Collision safety in our cars

Post by oprn »

That looks tail heavy. I'm thinking you might want to upgrade those rear brakes.
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oprn
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Re: Collision safety in our cars

Post by oprn »

Here is another cage that is grossly overbuilt in one area. It has bars going forward to the front suspension adding some front collision help. The roll part of the cage looks more than adequate and the rear protection looks to be good enough to withstand a Sherman tank hit. However the sides of the Buggy in this case are completely neglected.
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oprn
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Re: Collision safety in our cars

Post by oprn »

Now at the risk of sounding critical, I have been following that built and he is running a nearly stock 1600 in that Buggy so... maybe with his power level, the added weight... add to that, no windshield and the eye watering that produces at speeds above 40 mph perhaps a rear collision IS his highest risk. A helmet with a good wrap around visor is going to be minimum requirement to drive that at any speed.
Ol'fogasaurus
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Re: Collision safety in our cars

Post by Ol'fogasaurus »

The rear brakes (none in front as this is for sand only) are disc brakes hence 2 pucks per rear wheel.

The cage on the red buggy not only it does look massive and "busy" but maybe heavy too based on it's material.

It would be interesting to know the logic on "why" and if there is any effect to a weight change in the front of the buggy (I am assuming the fuel tank is still there).

Sometimes, after talking to the builder, there are good reasons for things but then again... sometimes not!

Lee
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oprn
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Re: Collision safety in our cars

Post by oprn »

Ah! It looked to me in the picture like a drum brake backing plate. I understand that for sand only machines "go" is the focus, stop just happens automatically.

I think often times extra collision protection starts with a welder, some pipe, "lets put a piece about here..." and just grows from there.
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Re: Collision safety in our cars

Post by Ol'fogasaurus »

People out on the dunes riding in the forest trails in the sand don't look or don't get to see and they go like stink... them BAMB!

Front brakes can dig in and rip the steering wheel out of your hands. Rear brakes are for stopping at slower speeds very well especially the rear disc brake setups. Since they don't (as I remember) have a parking brake setup, and in almost all of WA (there are 1 or 2 areas where they can be had and used, the turning brakes are illegal on the street. Not sure in other areas.

Lee
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oprn
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Re: Collision safety in our cars

Post by oprn »

All rear disc brakes built for the street have a parking brake. You need one to pass an on road safety inspection. Off road you are on your own. My sand rail doesn't have one and it's a total pain. Every time you stop and get out to open a gate, move a boulder, take a pee, whatever... you have to shut the engine off and leave it in gear or the car screws of on you and hits something.
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