Who Knows CF?
09-09-2008, 02:47 AM
#1
Senior Member
Thread Starter
Join Date: Mar 2002
Location: Ky
Posts: 2,723
Im wondering how well it would work for a floor pan and if it would need to be done like steel or a flat peice be just as strong? This is not for a rx7 btw and im just more curious as to it for the moment. I guess i should also ask how much molds differ between FG and CF if at all.
09-09-2008, 04:33 PM
#2
Super Moderator
Join Date: Sep 2002
Location: Savannah, Ga
Posts: 2,763
Carbon fiber, or any composite for that matter is not well suited to large flat pieces, unless it has a core. It can be done stronger and lighter than steel, but it has to be designed into it by use of a core or strategic bracing. Not to mention you cannot have any metals in direct contact with carbon fiber except titanium. The action of galvanic corrosion is bad with aluminum and steel especially. So you have to put a layer of fiberglass anywhere will metal will be touching the panel.
The techniques between cf and fiberglass are basically the same, just carbon fiber is harder judge when it is right. You cant see bubbles, voids, or resin lean areas in carbon fiber like you can in fiberglass. Its also very difficult to get an ideal resin to fiber ratio with hand layup. Autoclaves manage about 30% resin/70% cloth, but the best you will get with hand layup is around 50%/50%. The more resin in that ratio, the heavier and more brittle the part will be.
Assuming you are talking about the floorpan on the lotus 7/locost 7, you are looking at nearly $1k in materials.
The techniques between cf and fiberglass are basically the same, just carbon fiber is harder judge when it is right. You cant see bubbles, voids, or resin lean areas in carbon fiber like you can in fiberglass. Its also very difficult to get an ideal resin to fiber ratio with hand layup. Autoclaves manage about 30% resin/70% cloth, but the best you will get with hand layup is around 50%/50%. The more resin in that ratio, the heavier and more brittle the part will be.
Assuming you are talking about the floorpan on the lotus 7/locost 7, you are looking at nearly $1k in materials.
12-19-2008, 05:29 PM
#4
Junior Member
Join Date: Oct 2007
Posts: 19
Originally Posted by mazdaspeed7' post='907667' date='Sep 9 2008, 02:33 PM
Not to mention you cannot have any metals in direct contact with carbon fiber except titanium. The action of galvanic corrosion is bad with aluminum and steel especially. So you have to put a layer of fiberglass anywhere will metal will be touching the panel.
Can you explain more about this? This is the first time I've ever heard of this issue.
Is there somewhere you can point me to to learn more about composites?
12-19-2008, 07:16 PM
#5
Super Moderator
Join Date: Sep 2002
Location: Savannah, Ga
Posts: 2,763
Originally Posted by Johnny Boost' post='913528' date='Dec 19 2008, 06:29 PM
Can you explain more about this? This is the first time I've ever heard of this issue.
Is there somewhere you can point me to to learn more about composites?
Is there somewhere you can point me to to learn more about composites?
When certain dissimilar materials are in direct contact with each other, there is a transfer of electrons between them. This is the whole premise behind a battery. Now, batteries are an extreme case of this, but it happens on a much smaller scale in many substances, this included. Heres a little more, and more can be found on google.
As for learning, use google. I could write a book, and still barely scratch the surface of whats out there. But others already have, a little effort in research will get you far.
Thread
Thread Starter
Forum
Replies
Last Post
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)