quote:

Originally posted by mlnielsen:
Those are photos of the "optional parts", as some are labeled as "graphite pattern", and others as "graphite". There are many other photos on their webpage.

You both are probably correct, in that it is not truly made from carbon fiber prepreg, but most likely is only made to look so for cosmetics.

The flat parts are labeled "graphite", and the molded parts as "graphite pattern". I bet the flat parts are water-jet cut from flat sheet of carbon fiber sheet.

For a crawler, I don't think there is much of a weight savings.

Makes you wander what they are actually using. Graphite is actually more brittle then carbon fiber.
mlnielsen,,, Sounds like you know a bit about the 2 forms of carbon with the way you worded your post,so I'm sure none of this is new to you.

mlnielsen hit the nail on the head

quote:

Originally posted by mlnielsen:For a crawler, I don't think there is much of a weight savings.

Thats all you gain from carbon fiber is weight vs strength. You can not even get a helmet dot approved made out of carbon fiber, never alone a Helmet with an SA rating for racing.

If you smacked something the helmet would just shatter. Most helmets use Kevlar in them and use an outer layer of carbon fiber for looks.

Since they wrote on their site about graphite, Im not even sure if it is graphite or carbon fiber..

Anyway,, If you were to use carbon fiber on a RC you would want it to have a tight weave like I have on my 1/10th scale chassis for instance.




I would not trust my chassis on a rockcrawler. God forbid it took some hits the chassis would be rendered useless.

Now I would use graphite "IF" it was injection molded and not a weave. That way even since it is a brittle material you still have thickness on your side. Allot of your higher end RCs use injection molded graphite and not just plastic for their parts. Graphite injection molded axle housings would benefit since it has a lubrication value to it. Not only would the graphite parts have a lubrication value on other parts it comes in contact with, like using a bearing. But it would also help with sliding/skidding over rocks.

Both carbon fiber and graphite have there place with the goods and the bads.
Pencil lead is actually graphite. I use graphite powder for lubricating parts that will bind,like
metal to metal contact on a sliding door for a parsons house. You dust the powder on the wheel
tracked so the wheels on the door slide better on the track. I have Graphite grease I use on my car

You can usually tell when a RC part is graphite since when, you try and carve it with an exacto blade; it is not easy to carve like your typical plastic the blade will more or less chip pieces
of the part and the part will look like it is made out of strands.

Anytime you work with graphite or carbon fiber you do not want to inhale it. Depending on what the makeup of the stuff is,, It really sucks to get it on your skin. Way worse then the itchy feeling
you get from your typical fiberglass

To fabricate parts from carbon fiber prepreg (carbon fiber fabric impregnated with epoxy resin), in the intricate geometries of an axle housing, would require extremely expensive tooling and an autoclave. This process is typical in aerospace, where structural integrity ensures fracture critical parts will not fail.

There's a new process where prepreg tape (woven tape instead of a wide roll) is chopped into 1/4" lengths. This bulk material is then compression molded into complex geometries in two or three part molds. While only 50-75% as strong as a fabric molded part, it affords the mechanical engineer greater design flexibility.

Here's one company doing compression molding.

CCS Composites

And here's an example of a comporession molded part. This part would be impossible to layup with woven fabric.



The Duratrax parts might just be carbon-filled ABS or other similar material. This is injection moldable in mass quantities, and low cost.

the piece that I am fascinated by, is their wheels. I want to see them in person to see how they did that. Even if it was just printed on I would like to see how they did it. The wheels look like they went through allot of unnecessary trouble if it is just painted/printed on. Why would one waste material on the inside if it was done this way. Now if it isn't, then I would love to see how they did it. I might have to just waste the money and Buy a set of the wheels just to have one

This message has been edited. Last edited by: Wayne S,

The pre-built (w/o electronics) is now available from TowerHobbies for $140.