It is time for my comeback... 2000-2500lb cornerweighed 3/S and 1000hp motor

[mb3000]

oh ok. the reason i asked was because i was watching some guys cut the doors on a monte carlo yestersay. they said that its still a heavy car even though its a back half car. dude, the difference between the door that was cut and the one not cut had to aleast by 50 pounds lol. that shit was hell of light compared to the one not cut. and that was per door!! some nice weight savings there.

If you didn't put it on a scale it doesn't mean anything. This is how bad information is spread.

[keo92stealth]

If you didn't put it on a scale it doesn't mean anything. This is how bad information is spread.

it was just a guess on weight bro damn

[J. Fast]

have you considered goin with carbon doors?
a cf door is lighter that the window thats in it.my doors were only 7.2lbs a peice without anything in them.

I've considered carbon fiber doors, and even threw some money to the breeze for them. After doing some homework for them I don't think they're a good idea at all actually.

I have a cousin who lives in Seattle. He works for an aerodynamics specialty group for Boeing. Last time he came out to visit I explained to him my CF door plans. He basically told me carbon fiber and fiber based structural material has outstanding "on axis" impact deformation strength. In simple english terms, you can impact it on a perpendicular plane with a hammer and it will bounce. If you hit it really really hard it just tears and delaminates.

The scary part is un-impacted "off axis" stress. Say you to try and strech it, bend it, hit it on it's parallel axis, or compress it off plane. Well, it explodes! When it explodes it splinters really really bad. For illustation purposes, should you have a compressive impact on the door you'd basically be firing a porcupine out of a cannon inside the cab. Put that type of structure right next to your body and.... Metal, while it's heavier, stays consolidated and doesn't splinter and explode into 1000 chards per square foot.

Great write up Jer. 30 pounds though? How thick is the bar? .120 roll cage tubing is just over 2 pounds per foot, how thick are these? I've always wondered about pulling those out and skining the door, but never did. Cool write up for sure man, good stuff.

It's XXS (double extra strong) so it's pretty heavy.

Last night I weighed the following removed from my drivers side door:

1) Glass = 11 lbs
2) Door bar = 13lbs
3) Window tracks, guides, motor, and all mounting hardware = 11 lbs
4) Door wiring harness and auto lock assembly = 3lbs

[Erron Spalsbury]

WOW! That is a thick bar! Can you measure the thickness for me? I'm just curious what they used for door bar supports. One other thing to note is the doors have catch locking latches on them as well. When the door is hit, it stretches inward and there is a U catch that holds the door in place. (in theory anyway) It's that latch looking thing just above the pin on the door frame and you'll see its mate on the door side. I have yet to pull anything from my door other than the door card itself. Still have the power windows. It's always nice when it starts to sprinkle and I look over at one of the windowless cars and laugh as the window rolls up. That's fun.... (warmer too)

I think you're cousin may be describing something similar to this...


Doors, hatches, fenders, hoods, are most likely no where near the quality we see in the above video. None of my carbon is true dry, kiln cured. It's mostly laid wet and room temp cured. I can't imagine the doors being a super high end process either. Probably the closest thing we have to that would be the drive shafts, but even they "broom" when their flexural limit is compromised. I'm curious what process they use for those.

[slage]

One other thing to note is the doors have catch locking latches on them as well. When the door is hit, it stretches inward and there is a U catch that holds the door in place. (in theory anyway) It's that latch looking thing just above the pin on the door frame and you'll see its mate on the door side.

That makes sense! I always wondered what that was for!

[fullracegt]

where to get them from.......?

André

i believe pit road m still sells them..they would be worth the money in build like this one.

[J. Fast]

WOW! That is a thick bar! Can you measure the thickness for me? I'm just curious what they used for door bar supports. One other thing to note is the doors have catch locking latches on them as well. When the door is hit, it stretches inward and there is a U catch that holds the door in place. (in theory anyway) It's that latch looking thing just above the pin on the door frame and you'll see its mate on the door side. I have yet to pull anything from my door other than the door card itself. Still have the power windows. It's always nice when it starts to sprinkle and I look over at one of the windowless cars and laugh as the window rolls up. That's fun.... (warmer too)

I think you're cousin may be describing something similar to this...


Doors, hatches, fenders, hoods, are most likely no where near the quality we see in the above video. None of my carbon is true dry, kiln cured. It's mostly laid wet and room temp cured. I can't imagine the doors being a super high end process either. Probably the closest thing we have to that would be the drive shafts, but even they "broom" when their flexural limit is compromised. I'm curious what process they use for those.

Good video Erron. Very good illustration of what Josh was describing to me. The F1 car model you linked to uses a 2' carbon fiber "off axis" crumple zone for the front end. Behind the crumple zone is an aluminum armor plate. The plate prevents the fractured chards from penetrating the fuseloge when the carbon fiber deforms and splinters.

Same case for the side impact... The crumple zone is carbon fiber (shaped in an arch, a shape we discussed in great length as far as strength) but the fuseloge is aluminum. Watch the impact footage a few times in slow motion and look at the debris field tracking. It's basically a shotgun blast in the impact direction. You can actually see the blast splinters bounce off the exterior of the aluminum fuseloge.

Watch that a few times and think about it for awhile. In the case of going with carbon fiber doors it's just the door and then your body. No CF door I know of comes with an aluminum plate on the backside for blast protection. The F1 car has one though, the fuseloge.

To answer your question on the door bar wall thickness. I mic'd it and determined the pipe diameter is 3.6mm +/-

[Erron Spalsbury]

Carbon fibre - F1technical.net



The Official Formula 1 Website

I think you may be thinking of the aluminum honeycomb material. The building techniques have improved so much over the last few years (decade or two), they use less and less of that every year, some not at all. (typically only flat surfaces like the floorboard)

But again, the doors wouldn't be made anywhere near this level. I doubt we'd have anything remotely close to a "shattering" effect. It would do what your hood did, break, but for the most part stay together. In all honesty, a side impact of this level from another car and the door would be the last of my worries. Knee, ankle, hands, elbows, that's the part that gets hurt from hitting hard surfaces inside the car. (that's if the head restraint and helmet, window net, proper padding on the cage, seat and belts all function correctly)

[MeTarzan]

Definatly want to see how light we can get

[Ninja Performance]

What fuel lines? Lightest you can use? and still be track legal...

-Chris