No question riveted would see the highest point load levels.

Anyway, Cast would/should work. It would need to be balanced the same as any other. Billet has the potential of being fairly pricey.
I'm assuming that aluminum would be the prefered [I'll have to look up which alloy is best for something with high cyclical loads.
Are you thinking you'd want one w/ a top ring or just a open face fan unit [like a turbo impeller]?

If we go cast, it is possible to put in a top ring which would help hold the blades at their top/outter edge w/ a billet unit it would be 'possible'
but very costly to machine in the top ring.

I'm not back to the office until Tuesday but I can get the details ready to get pricing together.

Jarrett Johnson
www.innovention-tech.com

----- Original Message -----
From: Ernest Christley <echristley@nc.rr.com>
Date: Friday, May 20, 2011 6:43 pm
Subject: [FlyRotary] Re: Blower experiment:  FAIL

> On 05/20/2011 07:35 PM, H & J Johnson wrote:
> > So your thinking that the centrifugal forces are what sheared
> the rivets?  It's pretty crazy how high the forces spikes could be
> from an unblanced fan. I've not see one yet that was just built
> and installed w/out being balanced and lived for any period of
> time. That kind of stuff fails spectacularly, once it starts to go
> you couldn't stop it fast enough to stop it from exploding.
>
> Can't argue one way or the other.  All I know is that it came
> apart
> completely, and I wouldn't trust another constructed that way to
> last
> any longer.
>
> > As far as cnc'ing one, sure that can be arranged. Are we talking
> from billet or a casting or..?  Material?
> Would a cast object be able to hold together?  I was thinking that
> with
> a CNC, a machined billet one-off would be the easiest route.
>
> --
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