Carbon axle

[ggodwin]

Hi ggodwin:
This is going to be a tall order to try to replicate safely without access to lots of engineering first.
Not to be a Pollyanna or anything, but are you prepared to take the hit if this thing fails in service?
Were you hoping to try to just copy a sample?
I can predict lots of failure points if you don't have the engineering in place first and I'll betcha BAC spent a good bit of upfront coin to figure everything out before they marketed their first axle.


Cheers

Marcus
www.implant-mechanix.com
www.vancouverwireedm.com

This is for personal use only. It would NOT be for sale or mass produced. There are versions that were outlawed by WKA but are still allowed by other sanctioning groups. We are just trying to gain 0.02 seconds / lap. If we can find any design that will be much stronger while shaving 60% of the weight off then we could explore.

 

[ggodwin]

regardless....your OP was a "Carbon Fiber axle"
Not a composite with arrooooneeeeeum.

Which is why I was only asking for a general direction or resource. I am not exactly sure what it would be called or what the best design would be. I didn't expect this forum to be able to solve the problem easily and move on.

 

[Joe Gwinn]

Patent is us7543895 (will expire in 2026) - use Google Patents to get a copy.

It is doable, but as others have mentioned, may not be worthwhile for one unit.

 

[EmGo]

I am just wanting to explore an area where we can gain 0.02 sec perlap by using something similar that also reduces 5~6 pounds off a 10.5 pound part.

Make it out of vascomax, thinnest wall you dare, that stuff will wind up like a spring without breaking, comes in tensiles from 250,000 to 350,000 psi. I'd probaly go with the 250 and a touch heavier cuz I'm a scaredycat. Hone the bore to get rid of stress risers.

Material is not cheap, however.

 

[DavidScott]

If you just wanted to insert the cabon fiber stiffener inside an aluminum tube then that is fairly easy. Braided carbon sock is easy to find and you would need a blader to fill with compressed air to hold the sock to the tube while curing. Still, there are a LOT of details even though it is relatively simple.
My experience with this is from making carbon fiber sailboard booms, a road bike frame set, and crank sets. You can not only save a lot of weight over metal but also control the flex to how you want it.

ICE won't touch your hobby project, unless someone there is into karting.

 

[Strostkovy]

If I had to guess, and I do, I would make a carbon fiber axle from a split mold (with keyway molded, or ideally splines) and pack a weighed amount of epoxy fiber mix into each side and tamp a clearing with a rod. Close the mold around a piece of surgical tubing, bolt it together really well, and pressurize the surgical tubing inside.
The mold would have to contain externally barbed ends blocks to attach the nonstretchy tube parts to so it wouldn't go kablooey.

 

[Peter from Holland]

As soon as I did read the header I was thinking polygoon shaft ? or round with polygoon ends ?
Would that be possible in CF instead of a keyway??

Peter

 

[cyanidekid]

"hey, so I just want to make a critical rotating part 60% lighter for my... and I don't even know what that carbon stuff is called"

not a promising start. I hope you have a budget in the 6 figures at least. you do know what F1 teams spend on parts like this don't you?

 

[Strostkovy]

Out of curiosity, has anyone tried crimping metal ends on a commonly available carbon fiber tube? I'd like to try something like that for robot linkages.

EDIT: though I guess epoxy would stick pretty well...

 

[technocrat]

how many horsepower?

 

[henrya]

If you just wanted to insert the cabon fiber stiffener inside an aluminum tube then that is fairly easy. Braided carbon sock is easy to find and you would need a blader to fill with compressed air to hold the sock to the tube while curing. Still, there are a LOT of details even though it is relatively simple.
My experience with this is from making carbon fiber sailboard booms, a road bike frame set, and crank sets. You can not only save a lot of weight over metal but also control the flex to how you want it.

ICE won't touch your hobby project, unless someone there is into karting.

Best answer so far. ^^^^^^^

 

[Peter from Holland]

If you just wanted to insert the cabon fiber stiffener inside an aluminum tube then that is fairly easy. Braided carbon sock is easy to find and you would need a blader to fill with compressed air to hold the sock to the tube while curing. Still, there are a LOT of details even though it is relatively simple.
My experience with this is from making carbon fiber sailboard booms, a road bike frame set, and crank sets. You can not only save a lot of weight over metal but also control the flex to how you want it.

ICE won't touch your hobby project, unless someone there is into karting.

A polygoon shaft can be made easely using this technique with a mould Reinforcing the ends with some additional layers of CF perhaps ?

Peter