Okemo 2 caged car crashes

[3rdgendennis]

Didn't that mustang have no (or too small) spreader plates? My main hoop actually did push through the floor, but the whole floor came with it. The spreader plates worked, and the whole floor deformed, rather than the tube going through.

I don't disagree that the cage should be tied into the frame. That's how I did the cage in my rally car, and how I will do any cage I install in the future.

[jkale]

The material problem I referred to isnt one that can be measured easily or seen visually. It is a problem with the quality and consistency of imported steel tubing. Incorrect composition and inconsistency seem to be the big problems.

Measuring tube diameter and thickness are easy. Determining the tubing in use is A500 Grade A rather than C or A513 type 1 1008 and not type 5 1020-1026 (DOM) is outside the scope of what we can reasonably do at tech.

That is true. Determining type of material used is impossible to tell at tech.

But that does not mean we should not have a simple, plainly stated rule in place that lets the competitors know what material is acceptable to use that is slightly more specific than the "magnetic tubing" rule.

The rule should label some materials, like ERW, and black pipe, as not compliant.. And give an example of what a good choice of material would be based on its strength and toughness.. It should also NOT rule out the use of some materials that are not as widely used, but will meet or exceed the strength of our "base" strength( A-513 type 5)... Like Carbon Manganese Steel, known as T45 or TuffDOM..

I also think there should be some wording somewhere in the rules that requires the main hoop to be welded to the chassis in multiple locations if the bottoms of the hoop are just sitting on flat plates(even if there are welded).. So the picture that RacingFrog put up never happens at our hills..

[3rdgendennis]

I also think there should be some wording somewhere in the rules that requires the main hoop to be welded to the chassis in multiple locations if the bottoms of the hoop are just sitting on flat plates(even if there are welded).. So the picture that RacingFrog put up never happens at our hills..

I don't disagree with this, but the spreader plates in my car worked. The factory pinch welds holding the floor to the rest of the chassis failed, and the floor itself moved. If the spreader plates were attached to the frame/door sill, I don't think it would have been an issue at all.

[jkale]

Dave,

Usually when I install a cage, the main hoop lowers(that sit on the plates) are always tucked into the inner rocker panel. I usually cut a notch in the vertical component of the rocker, plate the bottom and the sides. Then it all gets welded together. This way, you are not dependent on the floor pan welds.. I think that is what you were saying in your last sentence about the spreader plates.. Ill try to post a pic of what I am talking about..

[3rdgendennis]

That's exactly what I'm saying. If it was welded to the inner rocker, not just the floor, I don't think the floor would have moved.

[jkale]

That's exactly what I'm saying. If it was welded to the inner rocker, not just the floor, I don't think the floor would have moved.

Yea, I feel like that is a tiny piece of info that would be good to have in the regs somewhere..

[Chief Geek]

pushing harder than I should have in the corners to make up for lack of power in the straights.

"Lack of power in the straights" being a relative term.

Paul

[Mopar 151w2]

OK, I'm late to the party (reasons willbecome apparent in posts appearing shortly) . I've read through all these posts briefly. I'm the original authour of the current definition of rollcage in the NEHA rules. Further, at one time or another, I have advocated for virtually every change or upgrade discussed here.
Recently, I rather vehemently opposed a shift from our previous material spec, for several reasons - largely because the rule was changed from a somewhat vague, but workable form, to a poorly defined standard which is unenforcable and unrealistic, and must be ignored to accept many of the cars in our current field.
I get that somebody thought the word "magnetic" was kinda dumb - but it was one of the few things that Don, at that time, said he could enforce, along with diameter and wall thickness. Given what was COMMERCIALLY AVAILABLE at that time, it was marginally sufficent, as it did disallow crap like EMT and "Muffler Moly" (SAE 1005 exhaust pipe), as well as gooey-soft 300 series stainless. Now, because somebody outside our orginization bent Don's ear, and I apparently know too much (or something), we have a standard which gives the vaugest possible material reference ("mild steel"), and references a means of production ("DOM"), rather than a commercial standard or proper material specification.
For this effort, I have been subject to egregious villification, slander, ostracisim, and an attempt at banning me from this forum. Very few have seen the full extent of the shitstorm turned my way. Despite this, I presented language to the "concerned parties" which spelled out what is generally acceptable for rollcage tubing throughout the sport, in terms of the ASTM (American Society forTesting of Metals) specifications, which are referenced by most US suppliers of steel tubing. This survived a couple rounds of "simplification" with the general intent intact, and was headed for a vote to adopt by all 3 clubs - then something happened (in the part I was trying to stay out of) and it all fell apart. I have copies of that spec, as do several of the "concerned parties".
I'm willing to keep working on this, and other upgrades to our rules package. Particulary, those dealing with the rollcage and related structure, and the structure of the rules regarding them. In return, I would ask that a couple parties consider some apologies, and either some furtherance of their own knowledge, or the willingness to stay quiet while grown-ups are talking.

[3rdgendennis]

John, could you post somewhere what you presented to the "concerned parties"? As this is a member-driven club, I don't see why the suggested language should be such a secret. After my crash, I'd consider myself a concerned party. Regardless of what rules are/aren't added/modified in our rulebook, I'd like to see it to further my own knowledge for future cages.

[Mopar 151w2]

Here y'are - google the astm spec #'s, and you can find tensile, yeild, and % of elongation for the various materials.

Steel mechanical tubing meeting applicable commercial standards, primarily ASTM a513 & a519. Other materials, meeting similar standards (ASTM a36, a53, a106, a500, a512) may be indistinguishable in use, and will be acceptable as such. Material selection is ultimately the responsibility of the entrant.

Rough translation: "DOM" = a513 CREW = a513 CDS = a519 HREW, "square" = a500, a 519 "Schedule 40 pipe, Black iron pipe" = a53, a106 "Hot rolled plate/sheet" = a36
Also - super soft hydraulic line, "bender pipe', "muffler moly", 4130 NOT maintained in condition "n", sch.10 "Railing pipe", defective/out of spec., and the like, do not meet applicable ASTM specs for mechanical tubing, so they are disallowed under this scheme.