Re: Armadillo May 9, 2004

At 07:09 PM 5/10/2004 +0200, you wrote:
>John Carmack wrote:
> > http://www.armadilloaerospace.com/n.x/Armadillo/Home/News?news_id=257
>
>I have some doubts on the stability of the axles, as they seem rather thin
>compared to the surface and weight of the vanes. Eventual danger of bending
>fatigue of the axle at the place where it goes in the inner bearing or where
>it is welded to the vane, in case of strong flow induced vibrations.
>Are the bearing housings made from cast iron? There exist bearing housings
>of the same style but made from pressed sheet steel half the weight and no
>danger of brittle breaking. They come even in stainless steel.

The axles are 1/2" 316 stainless, which should be fine for the couple 
hundred pounds of static force they should see.  Vibration may be an issue, 
we will have to see...

The bearings are high temperature graphalloy in cast iron housings.  I 
thought cast iron was especially good for dampening vibrations, which is 
why it is common in bearing mounts.  On a 1600 pound vehicle, I don't sweat 
five pounds of bearings at all, but I would be interested in hearing about 
brittle breaking issues with cast iron mounts.

John Carmack