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ChrisR
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There is a good example of a carbon seat in "Composite Materials Fabrication Handbook #2" by John Wanberg. it uses a mix of plain, 2/2 twill and satin with PVC core in selected places. Most "aftermarket" carbon seats I've seen are a single solid layup with core stringers to add stiffness as certain points
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wochi
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I have that book. And it´s a good starter but the seat is very small so I´m affraid that the layup suggested can be a bit weak on a full size seat. There is a video of Status making their seats and they use a carbon fiber layer and throw a bunch of fiberglass inside at same time. And Status is a very expensive brand. So I think if I could over do it i won´t have a problem. Thanks all for the tips
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BlackNDecker
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How are you going to incorporate bracket holes for mounting? You won't be able to drill directly into the seat and expect it hold a bolt.
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wochi
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you can insert some metal plates between the layers when infusin and then drill
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The Fibreglass King
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Hello Wochi, What I do not understand with you is you come on to the Forum for advice, then to shoot down all the advice you get, Knock yourself out fella. Build the seat you seem to know best!!! |
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wochi
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The Fibreglass King (30/05/2014)
Hello Wochi, What I do not understand with you is you come on to the Forum for advice, then to shoot down all the advice you get, Knock yourself out fella. Build the seat you seem to know best!!! Regards. The Fibreglass King 😄
It was not my intention to shoot anyone down. I was just saying that I was aware of the risks of building my own seat. I did say "Thanks all for the tips". English is not my main language so what I write may not correspond to what i want to say. If that was what you understand from my words I apologise. If I knew how to build it i wouldn´t ask it here. I did a lot of searching but I could not find the info I need for this project. I´m not one of those that just ask before searching.
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ChrisR
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I think you are underestimating the strength and stiffness you can get from CF, the layup suggested in the book is (approx conversions) 2 layers 200 satin, 2 layers 275 plain fibreglass, 2 layers 675 12k twill, 1 layer 200 satin with selected core in places. just on it's own without core you are looking at a 3mm odd thick layup so it will be pretty darn stiff anyway then factor in a 1/2in core and the seat curvature and it "ain't go'in nowhere" I doubt my fibreglass sparco seat is thicker than that and it's CSM! But also, as mentioned a few times it's the mounting that's the problem (as always!) and will be the thing you have to think the most about.
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wochi
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ChrisR (30/05/2014)
I think you are underestimating the strength and stiffness you can get from CF, the layup suggested in the book is (approx conversions) 2 layers 200 satin, 2 layers 275 plain fibreglass, 2 layers 675 12k twill, 1 layer 200 satin with selected core in places. just on it's own without core you are looking at a 3mm odd thick layup so it will be pretty darn stiff anyway then factor in a 1/2in core and the seat curvature and it "ain't go'in nowhere" I doubt my fibreglass sparco seat is thicker than that and it's CSM! Someone who can understand me  That´s what i´ve been trying to point out. Even the known brands make tem CSM and they pass the tests. So if I over engineer like Warren suggests in my opinion I won´t have a problem.
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ChrisR
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While I stand by my previous posts, this is in addition... wochi (30/05/2014)
If you have an accident and the door breaks you will probably have razor blades in your direction so it´s worse than a seat. But if the point was me beeing aware of the danger, I already was aware of it. So I can´t see the point in keep posting "don´t do it". Yes but imagine that "shattering" while in contact with your body! Personally I would build in a layer of diolin and/or amarid to help keep the laminate in tact in the event of a structural failure, but in the event of a catastrophic crash and seat failure you would likely be in the "doo doo". If I was making a road car seat then I would add at least 1/2in of flexible rubber/foam liner between the seat frame and the occupant to help contain any fragments. If you look at the failure mode/pattern of CF vs CSM, CSM while being weaker and less stiff tends to fuzzy break, the edges while the can be sharp are a little softer, CF on the other hand will shard and literally be sharp enough to shave with as the fibres are a lot stiffer and "pointier" for lack of a better word, anyone who has mishandled the flash edge or broken edge of a CF sheet will agree (this includes me btw as I've been sliced up by this stuff a few times even with builders gloves on). I'd recommend doing a few test coupons for shatter testing first to see the difference by introducing other materials towards the surface, put them in a vice and (with appropriate personal protection) give them a whack with a lump hammer, you'll soon see what everyone is talking about and where the concern comes from.
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Matthieu Libeert
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As far as I read above they are not commanding you not to do it, it's more like it's kind of a risky project and like you say doors, bonnets and so on are dangerous parts as well to make out of composite materials. I wouldnt make any parts for my car out of carbonfiber myself, maybe only some decorative stuff like the mid-console and so on. About the lay-up I cant really help you out because I never did something like that. A thing you could do is make some calculations based on the weight of a seat. use a ratio of 50/50 fiber-resin... by doing so you still don't know the fiber orientation, number of layers or what materials used (CF/FG/Aramid)
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