New Belts again

[p99ro]

HI
Its Time to buy new seat belts again. So is this rule due to What? Does anybody know why we need to buy belts every two years when last year I was in and out of my car less than 30 times and maybe 50 in the year before. Less than 100 times. Now we IT drivers probaly don`t do more than 5-10 races a year and maybe 2 practice track days. With those few times in and out of the car I never have much wear. Is it because of Bio degrading materials in the belts. If I don`t have visable wear is it because of streaching. In Nascar they are in and out of 1 of there cars more than I am all year. If I ran a pro series maybe but I would rather spend the monies towards ? Something else. :birra:
Scott CRXsi 07 NER ITA

[jc836]

There are several reasons for this. One is that in time Nylon will stretch and deteriorate. I do not agree with the severityof the rule as written. However, I do believe that after any major inpact the belts need to be replaced. The failure of the Earnhart belts has been discussed here and in many other places. The current issue of Speedway Illustrated has an excellent piece showing installs that are wrong or that cause fraying due to entry/exit. I have wondered about this issue too. My car is heated garage kept under tarp. It is on track 3 weekends a year-there is effectively NO wear. Is 3 years unreasonable-NO. But, then again some folks are buying very expensive 5 year rated belts made of the SAME material as the 2 year ones How is the price justified--by the FIA tag and nothing else as I see it.
Just my humble view.

[JLawton]

FIA belts aren't always expensive...... Check it out

Got mine yesterday!

http://www.saferacer.com/5pocahaset.html

[tdw6974]

:dead_horse: Jeff, You are correct several sources for the FIA belts at $135.00 price range. Might just as well get the 6 PT mount at the same time. $135.00 Divided by 5 Yrs = $27.00 per year about the price of 10 Gallons of premium fuel :o ( in our Area) We also added a Hans Device for the driver as We moved to ITS. If at anytime the Belts show wear or any problem I'll junk them and get new. As a former Tech Inspector you can NOT even begin to believe what would show up for tech. :018: . Maybe the rule eliminates that question of replacing belts with the 2 yr SFI Rule and PLEASE watch them all the time for an problems. :eclipsee_steering:

[lateapex911]

The polite response is that it is the "idiot proof" rule.

Which means that we are protecting that one moron in FL, (or equivilent) who leaves his car out, in the sun, every day, and it gets rained on every aftrenoon at 4PM as the daily shower passes, then gets baked at 100 degrees, and repeats and repeates and repeats....

So that when HE smacks the wall in his old, faded, decayed belts and dies, his family can't sue for a new house, boat and vactation home.....

[Geo]

Oh boy, this is a topic you really don't want to get me started on.

IMHO (after considerable research), I think it boils down to a ploy to sell more belts. You see, SFI is an organization by and for the manufacturers.

[JLawton]

With the new belts I got, it came with a graph that showed the decline in strength over a 24 month period. If it's legit data, I'll replace my belts once a year!!

[Geo]

With the new belts I got, it came with a graph that showed the decline in strength over a 24 month period. If it's legit data, I'll replace my belts once a year!!
[/b]

It's flawed data. It's from a 40 year old study that simulates EXTREME exposure to the elements in an accerlerated fashion to simulate a 24 month period using a different type of nylon.

Nobody has tested just how strong the webbing should be. For all we know, 25% of the original webbing strength may be plenty. The SFI test is a total joke (I received the testing protocol directly from SFI).

[Bill Miller]

The polite response is that it is the "idiot proof" rule.

Which means that we are protecting that one moron in FL, (or equivilent) who leaves his car out, in the sun, every day, and it gets rained on every aftrenoon at 4PM as the daily shower passes, then gets baked at 100 degrees, and repeats and repeates and repeats....

So that when HE smacks the wall in his old, faded, decayed belts and dies, his family can't sue for a new house, boat and vactation home.....
[/b]

Jake,

How does this change anything if the guy uses 5-year FIA belts?

[924Guy]

As I read about this, it makes me think that perhaps all of us switching to FIA-rated belts might be the best way to send a message what we think of SFI ratings? No... oh well... if only we did have a voice!

As an aside, I see (from perusing the saferacer site) that they now have a 7-point G-Force belt setup for sale - latch-n-link or camlock - under the Pro Series line - very glad to see! Unfortunately, the 7-points are not FIA tagged, only the 6-points. Hmmm, hard choice.

[lateapex911]

Jake,

How does this change anything if the guy uses 5-year FIA belts?
[/b]

Well, the polite response is that THAT material has been okie dokied for 5 years of wash n wear!

Of course, it's probably the same damn stuff.

The impolite response is that it's all a bunch of crapola, and nothing more than a racket.

[jhooten]

Over the weekend I noticed my belts were expired. Just ordered the GFR-7001 6 point pull down Cam locks With FIA tags, MSRP 149.99 Of course by time I get home from work only one dealer is still open to place the order was a "small" shop on the left coast and charged full price. Shop the dealers listed on the web site and you can find them a bit cheaper.

On the G-Force web site they show only the 5&6 point pull downs with FIA approval.

http://www.gforce.com/products/harnesses/c...ouldersets.html (http://www.gforce.com/products/harnesses/camlock/cam_indivshouldersets.html)

[p99ro]

OK
Thanks for the input.
I still don`t know anything.
But I have to buy new belts.
But I guess Jake is the winner. It is about the guy who lets his stuff become a danger to himself.

Scott CRXsi #07 ITA NER :cavallo:

[Bill Miller]

Well, the polite response is that THAT material has been okie dokied for 5 years of wash n wear!

Of course, it's probably the same damn stuff.

The impolite response is that it's all a bunch of crapola, and nothing more than a racket.
[/b]


Ok, glad we're on the same page. ;)

[Chris Wire]

I know that this is a small light in a very dark room, but if you time your purchase properly you can actually get nearly three years from the same purchase.

The rule gives us until Dec. of the expiration year, so those belts that are purchased in Jan/Feb of 2006 are valid until Dec. of 2008. So you can effectively use the belts for the '06, '07, and '08 seasons.

A.

Restraint systems meeting SFI 16.1 shall bear a dated ‘SFI
Spec 16.1’ label. The certification indicated by this label
shall expire on December 31st of the 2nd year after the date
of manufacture as indicated by the label.

Every little bit helps, I guess.

[Scott Nutter]

That is exactly why I waited until now to get my new belts. My car is garage kept and probably sees 6 weekends and 3 test days a year, but even with that little exposure the belt from the cage to the seat was noticably lighter/weathered than the rest of the belt in a three year period. Then again I buy the ~$65 five point Latch and Link SFI belts, and use the old ones as bait to lure other potential addicts to our addiction or maybe they are simply used to impress their friends?

[leggwork]

next set of belts, I'll be looking for polyester belts, not nylon. Nylon stretches 20% while polyester is at 7%. Think of the 3' belt from your lap to the harness bar - 20% is over 7" that you're moving forward in a frontal collision.
cheers,
bruce

[gsbaker]

The Mil Spec parachute webbing we use in our Link model has been tested to hell and back by the Pentagon, which calls for its replacement every 13 years when used in a cockpit harness.

Of course, if we ever get it "SFI certified" you'll have to replace it every two years.

[lateapex911]

The Mil Spec parachute webbing we use in our Link model has been tested to hell and back by the Pentagon, which calls for its replacement every 13 years when used in a cockpit harness.

Of course, if we ever get it "SFI certified" you'll have to replace it every two years.
[/b]

Gregg, what is the basic material makeup of the webbing?

[gsbaker]

I'm not sure Jake, I'd have to check. I personally haven't followed the whole nylon-vs-polyester thing. When we decided to check out webbing our contacts said, "Oh, just use Mil-XXX-YYY-ZZ.ABC. Works great," which it does.

Remind me and I'll dig up the details. I will note that, except for the width, it looks and feels just like street car belting--same thickness also, 0.080" IIRC.

[gsbaker]

Found it: MIL-W-4088

Nylon, 1" wide, 0.045-0.070" thk, 2500# tensile strength. Here (http://djassociates.thomasnet.com/viewitems/webbing-and-tape/nylon-webbing?&forward=1) is a good example of how this webbing can be specified depending on the requirements.

We don't use the polyester so I can't help there.

[leggwork]

haven't done any research on their reputation, but RCI says that they will recertify a set of belts to SFI 16.1 one time for free (you probably pay shipping), so you can get 4 years out of the belts (or, I suppose, 6 years if you do it early in the year).

http://www.realtruck.com/productline/793/1..._belt_sets.html (http://www.realtruck.com/productline/793/13/1/rci_racers_choice_platinum_driver_restraint_belt_s ets.html)

cheers,
bruce

[planet6racing]

next set of belts, I'll be looking for polyester belts, not nylon. Nylon stretches 20% while polyester is at 7%. Think of the 3' belt from your lap to the harness bar - 20% is over 7" that you're moving forward in a frontal collision.
cheers,
bruce
[/b]

Yes, but keep in mind that, in an incident, the 20% of stretch in the nylon is used to decelerate your body. By changing to a 7% stretch, you decrease the amount of stretch used to decelerate the body and, by comparison, increase the chance of injury.

I know the polyester belts have been tested and accepted, so it is probably a minor point. But, I guess my main point is that, in this case, less stretch is not necessarily better.

[lateapex911]

Great point. In a recent and comprensive article in a motorcycling magaizine, they tested and compared dozens of helmets and analyzed the results with an eye to effective standards.

Amazingly, they found that the best helmets, which were those that imparted the smallest G loads on the head, were actually the cheapest. The ultra expensive helmets were probably able to protect the head in super high impacts, but the article suggested that those account for a very tiny part of the overall picture.

We don't hit walls in Indy cars. Our speeds of impact are lower. food for thought. Mr Baker? Car to comment?

[leggwork]

planet6racing,
that line of thinking is counter to what top safety experts like Joe Marko at HMS preach ... I believe the issue is that more stretch allows your body to get moving faster, then you come to an abrupt stop at the end of the stretch (which is equal in both webbings). I will admit that I don't fully understand the dynamics of these fast events.

cheers,
bruce

[leggwork]

Gregg,
I'm not an HNR expert, but I did sleep at a Holiday Inn Express last night ...

perhaps the experts could have just as easily directed you to
MIL-W-23561 WEBBING,TEXTILE,POLYESTER,LOW ELONGATION (May 1995)
instead of
MIL-W-4088 WEBBING, TEXTILE, WOVEN NYLON (Nov 1988)
(found these at http://global.ihs.com)

I haven't read them, but it looks like they are just specs on categories of webbing, versus something that says - this type of webbing is good for this situation. Is use in a parachute similar to use in a head and neck restraint (I don't know)? If you search the above link using "webbing polyester", you'll see lots of FORD and GM standards for seat belt usage. If you search for "webbing nylon" you don't see any references to seat belt usage.
Of course, the ultimate test is the sled and it sounds like the Link does fine there. Probably because the webbing lengths are so short, versus the length of harness belts.
thanks,
bruce





Found it: MIL-W-4088

Nylon, 1" wide, 0.045-0.070" thk, 2500# tensile strength. Here (http://djassociates.thomasnet.com/viewitems/webbing-and-tape/nylon-webbing?&forward=1) is a good example of how this webbing can be specified depending on the requirements.

We don't use the polyester so I can't help there.
[/b]

[gsbaker]

Actually, the experts suggested an alternative if the nylon webbing didn't work: Kevlar webbing. Zero stretch.

Somewhere around here we have a piece of Kevlar string about the size of dental floss. The breaking strength is 500#.

[planet6racing]

planet6racing,
that line of thinking is counter to what top safety experts like Joe Marko at HMS preach ... I believe the issue is that more stretch allows your body to get moving faster, then you come to an abrupt stop at the end of the stretch (which is equal in both webbings). I will admit that I don't fully understand the dynamics of these fast events.

cheers,
bruce
[/b]

Obviously, I'm not going to argue with safety experts (well, not here anyway!! :D), but I am a trained engineer and a test engineer in polymeric composite materials, so....

It takes energy to stretch materials. Though the same amount of force may cause 20% stretch in nylon and 7% stretch in polyester, the actual g's on the body should be lower over the 20% stretch due to the increased travel...

Well, I think of it this way: crumple zones vs. rigid cars. They put deformable structures in the car for a reason...

The counter arguement is that the Polyester belts are well tested (I believe they have been used in production cars for years), so it really is a moot point. (so why do I keep prolonging it? :D)

In the end, I just installed a set of FIA belts. It was only $20 more than the SFI belts. I don't know if they are Nylon or Polyester and, frankly, I don't care. I just hope I never have to test them...