Ciamillo carbon crank now with pre-launch offer information!

Discuss light weight issues concerning road bikes & parts.
Locked
artray
Posts: 1365
Joined: Fri Oct 07, 2011 2:08 pm

by artray

Carbon fiber and aluminum are at opposite ends of the galvanic scale. Soon as moisture is present and it will be i.e wet/damp roads or living near a coast then galvanic corrosion will occur and this crank will bite the dust. I have had this happen on a frame with a alu seatpost, the whole frame was wrecked. This crank needs a rethink IMO .
Mattias Hellöre :thumbup:

RichTheRoadie
Tinker, Taylor, Tart
Posts: 1997
Joined: Sat Nov 29, 2008 8:00 pm
Location: Sydney, Aus.

by RichTheRoadie

I know it looks like aluminium, but do we know it is? I realise it probably and most likely is, but I'm just curious...

User avatar
bura
Posts: 841
Joined: Mon Mar 01, 2010 8:07 pm
Location: Civitatis Vaticanae

by bura

BikeTart wrote:I know it looks like aluminium, but do we know it is?

This is exactly my thinking. Mathias' as well as some other comments are way too definitive for me.
We may wait for the pics Ted promised us.
Kuota Kom Evo
viewtopic.php?f=10&t=111825&p=955235#p955235" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;
SOLD

bikedoc
Posts: 642
Joined: Thu Aug 16, 2007 3:16 pm

by bikedoc

My guess is they needed money so took deposits on something that doesnt exist to help cash flow. We know already that no one is getting what they put a deposit on as the design keeps changing.

User avatar
Mattias Hellöre
in the industry
Posts: 554
Joined: Fri Sep 23, 2005 6:34 pm
Location: Insjön, SWEDEN
Contact:

by Mattias Hellöre

Based on experience.

Aluminum - galvanic corrosion to carbon fiber is a very apparent problem.
Magnesium - the same applies here, even worser as slightest scratch on surface does let the Mg rot very quickly, likes to burn up your swarfs.
Titanium - too heavy and very hard to machine and requires stable machines and good tooling - not exactly cheap either.

Then you are running out of possibilities.

The only alternative is left here - Aluminum, I have hands on experience on aluminum in various constructions, I can say anodized aluminum is the worst possible material to bond on carbon fiber, the glue bond will release from the anodized surface faster than you eat up your Jell-O.
Experimental Prototype

User avatar
runner999
Posts: 326
Joined: Wed Jan 03, 2007 12:01 am
Location: Bay State

by runner999

This raises and interesting point about aluminum/carbon bonding methods. How is the bonding of aluminum spindles and pedal thread inserts different as seen on most carbon cranks? We also see aluminum mixed with carbon on many bicycle components. Please clarify how this is different. :roll:
Last edited by runner999 on Mon Dec 03, 2012 11:19 pm, edited 1 time in total.

topflightpro
Posts: 806
Joined: Tue Jan 13, 2009 2:35 am

by topflightpro

I too have experienced issues with galvanic corrosion between carbon and aluminum. My System 6 is flaking apart at the joints.

My other thought on this design is what is to keep the crank arms from twisting? I could see that being a problem, though I am no engineer.

ZeroG
in the industry
Posts: 156
Joined: Thu Feb 05, 2004 3:53 am
Location: Athens, GA
Contact:

by ZeroG

I will have a full explanation on the design at a blog I have been working on which will have detailed information on the design, the changes, and the construction. I am fully aware that this this is a radical change from the previous design that we did the pre-order .. but sometimes it's right in the thick of battle that you figure out how to win the war. This design is incredible on so many fronts as it solves the all the problems I had with previous designs. The photo that was posted is a process photo and there are several elements to the design that are yet to be revealed including the the aero cover.

The most exciting thing about this design is the attachment of the tubes which do not rely on bonding nor press fit. I am taking photos of the construction process because the technically minded will appreciate the details of a radical design.

I'm almost finished with the blog and will post the address shortly.

Thanks,

Ted

CarpetFibre
Posts: 599
Joined: Thu Apr 01, 2010 10:24 am

by CarpetFibre

:popcorn:

This is entertaining to watch in many ways. I look forward to seeing what you've come up with Ted, although I will need serious persuasion to ever swap out my Claviculas.

User avatar
CharlesM
Posts: 5771
Joined: Tue Sep 26, 2006 12:37 am
Location: Phoenix Arizona

by CharlesM

Interesting assumptions being made...

There are loads of alu/carbon rims around that have had no issues at all. I have a couple of sets that are 6 years old plus with several thousand miles on em and no problem.

uraqt
Posts: 814
Joined: Mon Apr 03, 2006 8:53 am

by uraqt

I have said it before and will say it again!!!

Go TED GO!!!!! : )


C

User avatar
elviento
Posts: 1235
Joined: Thu Aug 25, 2005 7:09 pm
Location: In the industry
Contact:

by elviento

However critical people are doesn't change the fact that it's great to see someone experimenting with new designs and new ideas. IMHO, this makes WW great. :thumbup:
Fast falcons: http://www.youtube.com/watch?v=j3mTPEuFcWk" onclick="window.open(this.href);return false;
www.falcobike.com
Facebook: falcobikeglobal

User avatar
itsacarr
Posts: 733
Joined: Fri Nov 14, 2008 4:55 am
Contact:

by itsacarr

+1 on one the simple fact people love to be critical - which is fine - ultimately you don't have to buy it if you don't want it but it's rad that a fellow weightweenie is making something new as a few others have done on this forum. Looking forward to reading more about it.

User avatar
Mattias Hellöre
in the industry
Posts: 554
Joined: Fri Sep 23, 2005 6:34 pm
Location: Insjön, SWEDEN
Contact:

by Mattias Hellöre

Charles:
You can have an insulating layer quite easily between an alu brake track and a carbon rim.
Same thing for bonding axles and other applications on a bicycle. You have here something that is groundbreakingly light and arguably takes the highest force on a bicycle IN SHEAR.
So why is this different? Well you need to put a insulating veil between the materials. How will this veil hold up to the shear forces and how much does it weigh?
That graphite fibers produce a large galvanic potential with alu alloys (Alu is anodic to carbon) is a firm established scientific fact. This is stopped by using either CIC ( Corrosion Inhibiting Compounds) or sometimes a sacrificing anode. Please note:
It matters not one iota if the materials are bonded, pressed or kept together w pixie dust.
So I guess the question is: How is this done here?
Quite a few composite tubing manufacturers also specifically cautions against the use of alu with carbon composites..


Source:
http://www.boeing.com/commercial/aeromagazine/aero_07/corrosn.html
Experimental Prototype

RichTheRoadie
Tinker, Taylor, Tart
Posts: 1997
Joined: Sat Nov 29, 2008 8:00 pm
Location: Sydney, Aus.

by RichTheRoadie

A link from Boeing... An industry where corrosion will be no doubt accelerated due to the constant changes in altitude, air pressure and speed; not to mention the massive differences in speed over a bicycle.

Can we stop speculating until we know the facts?

Locked
  • Similar Topics
    Replies
    Views
    Last post