Requirements for a carbon fiber seat?

[Sam Strube]

Hi everyone.

Has anyone here built a carbon fiber seat?

Also, what are the requirements for the mat?

Weight? Weave? Twill? Tow Size? Thickness?  Number of layers?  Resin?

I am going to build a carbon fiber seat for our modified roadster... and need some direction.

I looked in the rulebook and it doesn't give any details.

Thank you,

Sam

[maguromic]

Maybe Kent will chime in.  He has built and received approval for his carbon seat in the liner. Just buy one of his, we are putting one in my buddies rear engine roadster  I think its also been tested at speed. Love ya Kent.  Tony

[1212FBGS]

yep i have built a few..... do you have a plug or tool?
kent

www.motorcyclebodywork.com

[manta22]

I heard that seats were going to be required to be made out of metal; is this true or not?

Regards, Neil  Tucson, AZ

[Dynoroom]

I heard that seats were going to be required to be made out of metal; is this true or not?

Regards, Neil  Tucson, AZ

Neil, rule book page 26 2009. 3.D.1

The seat shall be constructed of a metal or alloy sufficient to retain the driverunder high "G" loading. Composite seats must be pre-approved by the technical committe.

[interested bystander]

The metal seat thing seems to be a myth going around.

Have had to build a metal  one recently because of the FEAR /misinterpretation. (.063 aluminum.)

Yrs truly's  understanding the rule was to keep out the "dune buggy" seats made out of ABS (motor home sewage tank) material, but it does make it tough for folks of CREDIBLE nature, like 1212, to get an approval.

Back abt '83 yrs truly built a dragster seat from .040 (center) and .032 3003 aluminum (sides). It survived a walk-away 175 mph (time slip speed ) crash.

MAYBE -only questioning- the rule is too general.

To resond to the original post, and the early response.  Contact 1212 - get his product.

If you're absolutely CERTAIN you want to do your own, contact Aircraft Spruce and ask for Josh Solis and get his advice.
They'll supply everything you need. Not recommended unless you're REALLY familiar with that type work.

In time, EVERYONE will be required to pour the foam beads and catalist  inside the bag and squish yer butt around till it sets up.
It's actually '70s technology that't trickled down to us poor folk. And the producers of those products are lobbying all race associations HEAVY!

[maguromic]

In time, EVERYONE will be required to pour the foam beads and catalist  inside the bag and squish yer butt around till it sets up.
It's actually '70s technology that't trickled down to us poor folk. And the producers of those products are lobbying all race associations HEAVY!

Heaving been in a bad wreck at Willow Springs I can attest that the bead seat inserts  work well. That and the seat belts were the only thing that was holding me when my seat snapped in half after heating pit entrance at about 125mph.  Its cheap insurance as it could have been far worse. Tony

[manta22]

Thanks, Guys.

Regards, Neil  Tucson, AZ

[Sam Strube]

Thanks guys.

Just a little more info.

The seat is going into a Modified Roadster... and to get the seating position nice and low, and to fit the area I have for it, it has to be a custom seat.

I took the design of the spine from a friend's seat out of his IMCA modified. This is the seat, which has excellent support in the spine and shoulders.  These guys wad their cars into balls of metal against guard rails, walls, and into other cars, on a regular basis, and their seat development has benefited from the unfortunate injuries and deaths...


They have really good support in the upper back area.  The race seats that are universal, such as the KIRKEY seats and such, don't have very good support in that area.  I bought one, and in the driving position, there is an inch and a half gap between my shoulder blades and the seat. 


Most seat backs are straight, this one is curved.

This is the curve of the seat copied from my friend's seat... since this picture was taken, we have begun to make the rest of the mold.


I have a friend who is a carbon fiber professional... he'll be making it after we make the mold.

Sam

[Peter Jack]

If I were building a seat now I would probably copy the seat you've copied only make it even bigger. It looks well supported and I like the shoulder supports. I'd build it out of 1/8" material, probably 6061T6. I'd then mix up a bag of the material they use for the Indy car seats. I believe the term is Bead All. It's a mixture of what appear to be Styrofoam beads and a very small amount of resin to hold the beads together. The bag is thoroughly mixed by kneading it pretty much until your arms get tired and then roughly forming it to the seat. Pop the driver in and let him sit there in his driving position until the mixture sets.

Help him out of the now form fitting seat and let it cure overnight. They then cut the foam off center down its length so it can be removed from the shell, yet still offers full support in the spinal area. Carve away any foam that isn't offering support or that's in the way and cover the remaining foam with gaffers tape. The seat can then be test driven in that form to ensure that it fits correctly. When the result is correct the seat is then covered with Nomex material to make it fire resistant.

The result is a perfectly form fitting seat giving absolute support and at the same time offering energy absorption in the event of a crash. The disadvantage to this method is that everyone driving the car needs a separate liner unless they're very similar in build to the normal driver.

This is just a suggestion. Sometimes something like this will trigger other ideas that may lead to a better solution.

Pete

[interested bystander]

Use generous bend radii with 6061 -T6. It cracks!

Not what I'd choose -see above.

[Dynoroom]

This seat was $150 not counting the rework we did to make it do what we wanted.

http://www.landracing.com/forum/index.php?action=dlattach;topic=1424.0;attach=346;image

[Peter Jack]

Good comment IB. I tend to use flat panels or make bends broken around a pipe. The foam takes up the gaps that are formed and the flat panels form a strong structure.

Pete

[John Burk]

For my seat I started with 2 pieces of plywood with slats between them with screws and kept moving them till it felt just right with the right lumbar support and experimented with templates to find the right side to side shape and side support . 

[Sam Strube]

Unfortunately the seats that you can buy do not allow my right leg go where it needs to be... which is over on the right side of the transmission to operate the gas pedal.  You might be able to tell from the picture, pictured.

Incidentally, we had carbon fiber expert #2 come by yesterday... extremely talented guy with 40+ years experience working with composites... he told us how to finish up the mold... and he'd take it from there. 

My only worry is... "what are the requirements for a composite seat?"

My fear is that we get the thing made, and it doesn't pass tech because of some small detail we didn't know about.

Lastly... what is the "pre-approval by the technical committee" process? 

It sure would be neat to come up with an in-depth rule book with specifications, materials use, and common practices for a lot of these little things that make up a race car.  There is a lot of info that people have... that needs to be written down for everyone to access...   

Sam