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Ok, F1 cars run carbon chassis so it's possible. Take the following with a grain of salt, I'm not a composite's engineer. No material's magic, carbon fibers (regardless of type) are strong along the axis of the carbon. IE a sheet of carbon won't deform along the edges, and won't bend but most likely they won't take as much load pushing hard into a plate 90* to the fiber's axis. Axial wound could be good stuff, and properly designed might actually make a good cage.

Some of my concerns: Maintenance is going to be far more important. Steel tube cages will show obvious bending and cracking if they're damaged, carbon can suddenly let go with no warning, so inspection is way more important. Design is significantly tougher, metals have some great properties that make them easy to design with. Carbon layup schedules become hypercritical when designing structural stuff, along with that comes expensive software packages. Last for today, with a normal cage you can build to the series' spec and that's good. With CF as structural members, you're going to need a PE with experience to check the design. If you don't have that, I doubt you're getting on track with it outside of track days. If that's the case please don't do it, playing fast and loose with people's safety isn't cool. If you're looking to add some stiffness take a sheet of normal carbon fiber or aramid, come up with a solid mounting scheme and run it from rear strut to rear strut and attach, run down to the floor, then test, it might be a decent amount better.

~Pat

I understand the concerns with the CF Cage, I don't plan to make an entire cage, more of a roll bar similar to this:

Design Innovations: Carbon Fiber Rollcage Corner Balance

Its in Oakley designs Porsche. Interestingly they found a way to make it create an anti splinter affect, which I believe I know what they used. But some testing and some experimenting at the shop should help me figure it out as well.

Luckily, I have a cousin who just finished up in Mechanical engineering and I have a couple other buddies from when I used to work at an architecture firm that are structural engineers. I haven't talked to them about the project yet but I'll be seeing one next week and I'll ask him about it. I know he has used machines that calculate for load bearing carbon fiber support beams.

I don't plan to use this in my 350z, more just in the 240z behind the seats similar to the one in the link. I'll have to look up any rules and regulations regarding such a roll bar to be used at the track because I don't know of any.

Your right about Axial CF. The weaving machine they use is pretty cool to watch it do the weave around their metal jig.

This may be rumors and a myth, but I have heard of Coast Guard Ships using A pre preg form of CF in the bows of the boat. Supposedly they are able to cut a typical fiberglass/wood boat in half easily without a dent to their ships. I heard this from a guy who used to teach a pre-preg course.
 

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Wanted to ask if you had a chance to weigh the Asuka, Mastergrade, and Seibon hatches yet? Wondering what the difference is among them.

Hey, ya I was able to weigh the Asuka, Mastergrade, and Seibon hatches, forgot to post that I guess:

Asuka Double CF: 14 lbs.
Asuka Fiberglass: 16.5 lbs.
Mastergrade: 15 lbs.
Seibon CF (non dry):20 lbs + (I can't be certain because the customers car came in with the seibon hatch and OEM glass installed.
VIS CF: (should be the same as the seibon one, they both get their hoods from the same manufacturer, seibon just gets to badge them here and say its made in the US which I don't think they are saying its made here anymore anyway.

I haven't weighed the stock glass, which I will soon, but with a polycarbonate sheet that I weighed not even cut to the glass shape, I got 5lbs.
 

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I'm not trying to dissuade you, much the opposite, I'd love to see F1/LeMans tech come down market, but it needs to be done smart.
The Oakley/Porsche harness bar/roll bar was designed by composites engineers, same with the Naval ships. There are steps to doing it right, you're going to need a licensed engineer, and the tools they use. The machine your brother used isn't cheap (if it's what I think it is), I've got a buddy who's an engineer for one of the big companies in the field the going rate for a new, fully configured one is about $100k, you might find a good deal on a used one one. The design software is probably on the tune of $15k. On the flip side if you start going down that path, it opens up a lot of more valuable markets (think actual race cars). You're also in a good area to do it. SoCal has a lot of great engineers, including aerospace guys. Some might trade a lower salary for building cool stuff and playing with cars, I probably would.
In order to get something like that approved by the SCCA or NASA I suspect you'll need design documentation stamped by a California licensed professional engineer. There was a thread on a race site about simple design changes to the roll bar in an open wheeler, and that was the necessary process. I'm not a pro at this, composites aren't my thing, so talk with someone who knows them. ~Pat
 

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I'm not trying to dissuade you, much the opposite, I'd love to see F1/LeMans tech come down market, but it needs to be done smart.
The Oakley/Porsche harness bar/roll bar was designed by composites engineers, same with the Naval ships. There are steps to doing it right, you're going to need a licensed engineer, and the tools they use. The machine your brother used isn't cheap (if it's what I think it is), I've got a buddy who's an engineer for one of the big companies in the field the going rate for a new, fully configured one is about $100k, you might find a good deal on a used one one. The design software is probably on the tune of $15k. On the flip side if you start going down that path, it opens up a lot of more valuable markets (think actual race cars). You're also in a good area to do it. SoCal has a lot of great engineers, including aerospace guys. Some might trade a lower salary for building cool stuff and playing with cars, I probably would.
In order to get something like that approved by the SCCA or NASA I suspect you'll need design documentation stamped by a California licensed professional engineer. There was a thread on a race site about simple design changes to the roll bar in an open wheeler, and that was the necessary process. I'm not a pro at this, composites aren't my thing, so talk with someone who knows them. ~Pat
Hey Pat, thanks for the help and info. Its good to get feedback like this because it makes me think harder lol.

Ya, one of my friends has his own engineering firm with a couple partners, he and his partners are all licensed engineers and do structural testing. I know the machine they have is very expensive and is hooked up to a computer next to the machine. I don't know too much about what and how they do it since I was in architecture. I'll talk to him and get more info on what will be needed. My cousin just wants to do the number crunching since she was doing her thesis on carbon fiber nano tubes.

Were lucky to have a shop here in Costa Mesa because we have so many resources next to our shop to do what we do.

Composites are my thing lol. Thats what I do for a living. I'll try to get a video up of some of the parts we have made (like a BMW M3 Door) where we are trying to smash it with a hammer and a bat and were hitting it as hard as we can. These doors were done using vacuum infusion and were pretty strong for the layering it was made with. They weigh in at 12lbs per door oem were about 60lbs I believe.

Anyway i'll start up another thread with some information I have been meaning to put up on the forums about CF and some facts, myths, and some common questions and answers about CF/Aramid and composites.

Anyway, anyone have any info on the charcoal box removal? Can it be done and should it be done or should it not?
 

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sure, if you ship me a set for $100 in cf and let me test fit them, i'll run them without a cage lol j/k.. i'm more interested in seeing if you can figure out that roll bar
 

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If you want to open up more of a market, design them to meet some spec (beyond FIA spec, tested by an outside lab preferably, maybe DOT side impact). I'd be open to running composite panels, but wouldn't want to do so without knowing they're safe. The test shouldn't be when a customer gets hit by a semi truck. We don't get to play that way as engineers.

~Pat
 

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Lol still figuring out some things with the roll bar, I have 2 engineers I've been talking to about the project. We'll see how far we get. One of them brought up the door idea. We got a deal on some Honey Comb Core material which is super strong when done right.
 

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Carbon doors for street use scare me. If a car hit you on the door your done.

I've lost 70 lbs off the Z. When I put the roll cage I'll be back to normal...RRrrr
 

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This is what I've done to my car and my goals. Removed rear bumper reinforcement, wipers, wiper motors, wiper reservoir tank, spare tire, 2 1/2 pound hatch weight, speakers, radio, metal sound bar, all of the plastic interior panels in the hatch area, passenger and driver side windows, a/c system(Including compressor, lines, condenser, blower, vents, and controls), Titanium exhaust, fiberglass hood, smaller battery, and lighter mirrors.

If I ever come across some big money I'll change my front fenders, doors and hatch to carbon fiber.. And change my front and rear windshield to acrylic

I'm getting nervous about putting a fuel cell inside the car. How much do our stock fuel tanks weigh?
 

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:poke: You're crazy. Post pics. :lol:
 

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Right now the trunk just looks like I took off the plastics, it's not that exciting..:( I've been wanting to take the speaker bar off and wash the car. I'll take some pics after I'm done for you all.

I found a way to take off the speaker bar behind the seats. I'ma drill out in the spots where they tap welded (It's not a normal tap weld you can see and grind off. It's sandwich between the two peaces of metal). I've already taken off the 15 or so bolts that hold it down..

I took off 3-4 triangle peaces of aluminum from inside the hatch area. They're located on the back wall, around the latch area. Don't really know what they are for, but I know I'm not going to use them. All I did to take them off is grab'em and wiggled them left to right. You'll need a little bit of brute force but they come off fairly easy :D

I'm also getting a Sparco steering wheel and a Momo hub (part#3516). So I'll loose some pounds once I remove driver and passenger airbags. At the same time I'll prolly take off the pillar and roof airbags.
 

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This is what I've done to my car and my goals. Removed rear bumper reinforcement, wipers, wiper motors, wiper reservoir tank, spare tire, 2 1/2 pound hatch weight, speakers, radio, metal sound bar, all of the plastic interior panels in the hatch area, passenger and driver side windows, a/c system(Including compressor, lines, condenser, blower, vents, and controls), Titanium exhaust, fiberglass hood, smaller battery, and lighter mirrors.
I still need a bit to go on list to finish it off. I haven't done: A/c blower, vents, Titanium exhaust, fiberglass hood, smaller battery, and the mirrors.

Not sure if I'm going to do the fiberglass hood because most of the time they never match the lines of the car... I wouldn't mind keeping all the metal fenders, hood, doors, and hatch. To keep a little weight and reinforcement for top speed.
 

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Here's an okay video explaining how to take off passenger air bag. Keep looking threw his saved videos and you'll see more. You can see they removed some panels already when making the first video.:
 

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I've upgraded to a reciprocating saw and an angle grinder/cutter, so I can take out the sound bar. Ran out of blades so I couldn't take a finished picture. The sound bar is as good as out. The hardest part was getting into the inner structure of the sound bar, as seen in the first two pictures.

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