Carbon Fiber Pistons. Opinions please.

[97fbird38]

Carbon fiber parts for army gliders? the army is interested in using gliders again? thats really interesting, can u tell me more about it?

[strobhen]

I would work for minimum wage if I had that kind of priviledge... seems like a huge perk to me.

Do you have to pay for the materials you use?

make some carbon fiber rims & driveshafts [img]smile.gif[/img]

get creative, you could easily suppliment your income

[ July 05, 2002: Message edited by: strobhen ]</p>

[4thgenowner]

We could free up quite a few ponies with these new pistons. Less rotating mass to move, quite nice.. quite. Ricers eat your hearts out. ha! [img]graemlins/burnout.gif[/img]

[strobhen]

lol, my third post, but something insane just came to mind

why stop at pistons? carbon fiber camshaft, rockers, rods, valves, uhm... block... :D

I'm insane...

[93v6firebird]

reinforced super strong carbon fiber bumper... teach those tailgaters a lesson

[Roy]

wow, that is really cool. id like to know how it turns out if you decide to do it. should free up a lot of mass and and make a lot more power then. not sure how much pistons weigh, but look how much less energy will be lost pushing the pistons and, and it will be transfered to the wheels [img]smile.gif[/img] . wonder if the engine would run cooler too.

[nova]

<blockquote>quote:</font><hr>Originally posted by 97fbird38:
Carbon fiber parts for army gliders? the army is interested in using gliders again? thats really interesting, can u tell me more about it?<hr></blockquote>

The glider project didn't involve CF parts.

We're trying to determine a way to cancel out airflow noise so that aircraft can be used as sound detection platforms. This will most probably later move to powered aircraft.

I'm not at liberty to give much more info than that.

<blockquote>quote:</font><hr>Originally posted by strobhen:
Do you have to pay for the materials you use?

make some carbon fiber rims & driveshafts [img]smile.gif[/img]

<hr></blockquote>

I'll have to buy the resin and depending on the size of the part I'll have to buy the CF. Smaller parts I can probably use remnants that are laying around the lab, but larger parts will require full rolls.

I was planning on trying a driveshaft but I don't know about the rims. I'm not certain if the stuff can be chromed or not.

<blockquote>quote:</font><hr>Originally posted by strobhen:
lol, my third post, but something insane just came to mind

why stop at pistons? carbon fiber camshaft, rockers, rods, valves, uhm... block... :D

I'm insane...<hr></blockquote>

From the conversation I had with the engineer thats what he said NASA was working toward. A totally CF composite engine.

<blockquote>quote:</font><hr>Originally posted by Roy:
wow, that is really cool. id like to know how it turns out if you decide to do it. should free up a lot of mass and and make a lot more power then. not sure how much pistons weigh, but look how much less energy will be lost pushing the pistons and, and it will be transfered to the wheels [img]smile.gif[/img] . wonder if the engine would run cooler too.<hr></blockquote>

I'M not actually making CF pistons. That is a NASA research project that is not being conducted at our lab. I don't have the skill to make pistons. I probably couldn't afford the resin either.

I'm probably gonna make other parts though.

[Fat_kid_in_little_camaro]

I'm in school for engineering, but i'm in the electronic field. From what I've learned, the reason this would work for a rocket engine would be that the velcotiy is greatly affected by the M of the object.

Delta V = v(ejectedfuel) LN (M1/M2)

Using that formula, asssuming your initial velocity is 0.0 m/s, The less final mass you have after burning the fuel, the greater Velocity you are going to create. With carbon fiber having much less mass, then the final mass would decrease more proportianl to that of a steel craft.

Modeling this as a car engine however, you would have to model the Cam along with your piston as a rigid object with forces that would actually be comeing from all different angles. Therfore you can't really have a single formula that would relate for that. I'm sure the nasa guys have way way way more training than I, and are actually mechanical engineers so it may be no problem to them, but it would seem that the main problem, would be possibly be the Mass of the pistons since (Sumation)F= mass * acceleration. of course with the piston having a focre put on it, i'm not sure how that would work. I didn't go that far into the mechanical parts of it.

[nova]

<blockquote>quote:</font><hr>Originally posted by Fat_kid_in_little_camaro:
I'm in school for engineering, but i'm in the electronic field. From what I've learned, the reason this would work for a rocket engine would be that the velcotiy is greatly affected by the M of the object.

Delta V = v(ejectedfuel) LN (M1/M2)

Using that formula, asssuming your initial velocity is 0.0 m/s, The less final mass you have after burning the fuel, the greater Velocity you are going to create. With carbon fiber having much less mass, then the final mass would decrease more proportianl to that of a steel craft.

Modeling this as a car engine however, you would have to model the Cam along with your piston as a rigid object with forces that would actually be comeing from all different angles. Therfore you can't really have a single formula that would relate for that. I'm sure the nasa guys have way way way more training than I, and are actually mechanical engineers so it may be no problem to them, but it would seem that the main problem, would be possibly be the Mass of the pistons since (Sumation)F= mass * acceleration. of course with the piston having a focre put on it, i'm not sure how that would work. I didn't go that far into the mechanical parts of it.<hr></blockquote>

Don't feel bad if you don't know how the CF pistons all interelate. The guy I was talking to has a PhD. in Mechanical Engineering and he didn't even know how everything would react.

The parts are pretty much a go also. I learned that the best way to build them would be to lay up the CF on an existing part such as a fender. I'm probably going to hit up the junkyards next week to acquire a fender and do some experimentation. The only problem would be that the part I made would be slightly larger than the original but I think I can counteract this with some "tricks".

[Arctc Wolf]

Personally, I'd just be happy if they made cf hoods, front fenders, and t-tops. If you could get a piston/rod set together, that'd be tight. We'd finally be able to have an internally balanced engine, so we wouldn't have to worry about getting lightweight flywheels and weighted dampers. There's a lot you can do w/ carbon fiber, it's just that it's too damn expensive.

[Tiago]

do you guys know anything about CF?
Imnot sure if CF woudl work good for a piston.

the composite fibers in general, CF included, are only good for stress in tension mode, they don't hold up to much stress at all in the way a piston recieves it, I think a hole would blow thorugh it the first few fires, if not the first one.

what MIGHT work is a normal forged aluminum piston CORE covered with CF, alot of composite applicatiosn resort to this method to strengthen the structure for other stress modes.

[ July 13, 2002: Message edited by: Tiago NOS'd Bird ]</p>

[V6Bob]

"do you guys know anything about CF?
Imnot sure if CF woudl work good for a piston.
the composite fibers in general, CF included, are only good for stress in tension mode"

From

http://www.gogulftech.com/techform/default.htm

"The most dramatic thing about carbon fiber is its tensile strength. ...plus its compressive strength is, comparatively, much greater than fiberglass or most metals."

The Formula One boys use CF in compression all the time.

[nova]

<blockquote>quote:</font><hr>Originally posted by Tiago NOS'd Bird:
do you guys know anything about CF?
Imnot sure if CF woudl work good for a piston.

the composite fibers in general, CF included, are only good for stress in tension mode, they don't hold up to much stress at all in the way a piston recieves it, I think a hole would blow thorugh it the first few fires, if not the first one.

what MIGHT work is a normal forged aluminum piston CORE covered with CF, alot of composite applicatiosn resort to this method to strengthen the structure for other stress modes.

[ July 13, 2002: Message edited by: Tiago NOS'd Bird ]<hr></blockquote>

Heres a private corporation making carbon pistons using the NASA process. I was under the impression that it was research project but it looks as though it has been licensed for production. This particular application is a carbon-carbon process which is actually different from what we do at the lab I work at. It utilizes carbon embedded in carbon instead of carbon embedded in a polymer resin.

Just hit cancel when it asks for a password.

http://www.hr-incubator.org/carbon.doc

Here's some more info on the different carbon fiber composites.

http://callisto.my.mtu.edu/MY472/class14/class14.html

[Tiago]

cool [img]graemlins/thumbsup.gif[/img]

I wonder how the low coefficient of expansion would work out being that the block does expand, and the piston wouldn't?

[Arctc Wolf]

iron wouldn't expand that much. if you really worrk about it, then get cylinder sleeves made in cf. One thing I'd really like to have made for our cars is deck height addition. this would be good if anyone in the future ever came out w/ a stroker kit for our cars. I've heard of them being used on imports to add 1/2 to 1" to the deck height. It's just an idea. If I'm wrong about seing them on imports or them being able to be used w/o worrying about the engine, sorry.