Re: Re: pitch block trivia

From: Nick Ray <lasray_at_gmail.com>
Date: Thu, 3 Jul 2008 18:30:59 -0400

John,
You are right thanks for catching that. I was thinking about taking the
arctan to get the angle when solving the equation and my mind got ahead of
my fingers.


On Thu, Jul 3, 2008 at 12:52 PM, Mark <f1diddler_at_yahoo.com> wrote:

> --- In Indoor_Construction_at_yahoogroups.com<Indoor_Construction%40yahoogroups.com>,
> "John Barker"
> <john.barker783_at_...> wrote:
> >
> > It seems to me that if wanting to form a 28" pitch propeller on a
> 26" pitch
> > block that the blank would need to be moved inwards, not outwards,
> to use
> > the higher forming angles.
>
> I don't see that. Going inward (closer to hub, shaft) on my pitch
> blocks amounts to a faster rate of angular change per inch of
> diameter, and I associate that with lower nominal pitch. Crudely
> said, higher pitch props have "less twist" over the whole blade.
>
> <<. Note that this is the change of angle from end to end of the
> blade, the blade must still be set on the spar to get the correct
> pitch. However it does indicate the blades formed on less than
> perfect moulds (or evenbottles!) can perform as well as they do.>>
>
> We can agree there, and the very reason I titled this "trivia"
> although triggered in actual building.
> Mark F1diddler
>
> (Gotta check out until after Kibbie Dome Anuual.)
>
>
>


[Non-text portions of this message have been removed]
Received on Thu Jul 03 2008 - 15:31:10 CEST