Alan,=0Afilling dings in the leading edge won't have much effect but uneven
painting could. It is possible to check the balance statically using a sca
le=0A=0Aaccurate to a tenth of a gram. You will need to make a jig with a k
nife edge pivot at one end, which effectively- represents the centre of t
he prop.=0A=0AEach blade is fixed on the jig in such a position that it's r
oot end is the correct distance from the centre. Now a second knife edge (o
r indeed a single point) at roughly half the length of the blade, (not crit
ical) is placed on the scale and the weight noted. This weight is now the "
moment" of that blade about the centre of the prop. Obviously the moment of
all three blades must be the same for good balance.=0AIt's interesting to
note that the weight of each blade may not be identical, it's the "moment"
- (= weight X distance) that must be the same.=0AHope that's clear?=0AW
e used to balance wooden props to respond to the weight of a postage stamp
on one end using a pair of level knife edges and the prop on a central spin
dle. We used an extra coat of paint to achieve final balance.=0AThe Arplast
blades have a 1/4" hole drilled from the root to about 1/3 span. Lead shot
was used to achieve balance, sealed in with epoxy resin.=0A=0AGraham=0A=0A
=0A________________________________=0A From: Alan Carter <alancarteresq@one
tel.net>=0ATo: europa-list@matronics.com =0ASent: Wednesday, 26 September 2
012, 23:11=0ASubject: Europa-List: Arplast PV 50 Prop=0A =0A--> Europa-List
message posted by: "Alan Carter" <alancarteresq@onetel.net>=0A=0AHello All
.=0A1. I have a Arplast PV50, if a prop can be called a wobbly prop the PV
50 fits the bill. =0AIs there a PV 50 owner out there who can give me some
information on this prop.??=0AThere is no UK agent.=0A2.I have been filling
the chips in the leading edge with Araldite and repainting- the tips.=0A
The prop is about 10 years old and done about 400 hours,?? i have no idear
when it was last- balanced, but it seems OK in flight.=0A"Some say" it wi
ll need re balancing, in an ideal world i would go along with that, but its
not an ideal world,and the use of common sence needed.=0AHowever i stand t
o be corrected if needed.=0AI now nothing about balancing props,but think t
he prop could now be slightly more or slightly less inbalance,but with into
lerance.=0AThe only way to really know is to check the balance before then
after the repairs, and see the effect. We are talking about small repairs n
ot big dobs of paint. =0AHas anyone done this, and can give an answer.=0A
=0AAlan=0A=0A=0A=0A=0ARead this topic online here:=0A=0Ahttp://forums.matro
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