LPP Prop Problem

From: LeRoy C Cordes <lcordes_at_juno.com>
Date: Fri, 16 Nov 2007 12:30:29 -0600

I have a problem ! When I started in LPP a year, or so, ago I made up 3
props following Cezar Banks' LPP Plan. They are all made to 22 degree
pitch with a hardwood hub and balsa blades glued with thinned Ambroid. I
flew on all these props all season and they were Ok to good. This fall
when I opened my indoor containers I found a puzzle - the first prop,
which had very soft balsa blades to which I had added a rib at the ends
of the prop hub (because the prop was flaring too much), the blades had
somehow moved on the hub to where they are parallel to the prop shaft
wire (90 degrees to the direction of flight). The second and third props
were still flyable but one of the blades on each prop was way off pitch
having rotated 10 or 15 degrees in the direction of prop number 1 ???????

I've now made a 4th prop and I don't want this to happen again - any
ideas what caused this to happen ? They have all been stored with the
prop hubs horizontal captured in a piece of foam thad didn't touch the
blades and didn't allow the blades to touch anything else. They were
stored in realtively sealed plastic storage boxes that also contain my
models.

Appreciate any help

LeRoy Cordes
AMA 16974
Chicago, IL
In God We Trust
Received on Fri Nov 16 2007 - 23:30:34 CET