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Re: Europa-List: Weight and Balance Scales

Subject: Re: Europa-List: Weight and Balance Scales
From: pjeffers@talktalk.net
Date: Thu, 24 Mar 2011 08:47:21
=0AHi Bud,=0A=0AHow much I concur with your advice re weighing
.  =0ASome years ago I bought (from Spruce) a set of sca
les said to be suitable for aircraft weighing.  They turned 
out to be ordinary spring operated bathroom scales dressed up 
with a fancy system designed to half or third the load on 
each scale to bring them within weighing range.=0AI weighed on
e aircraft with this equipment and was not satisfied with th
e result so did it again with the same care and ended up
 with discrepancies of  up to 10 % between results (just 
move the a/c an inch to one side of exact centre on the 
pan and see the weight change (scary). I now have a set 
of calibrated electronic scales from Sun'n'Fun.  They proved j
ust how bad the bathroom scales realy are. On these electron
ic scales you can put a calibrated weight literally anywhere 
on the pan and it reads exactly the same correct figure.  
Try this test with your bathroom scales and watch the result
s.  This test alone should prove how unreliable cheap scales
 are.  By the way it is interesting to note that good 
electronic scales are calibrated and then even biased acording 
to the lattitude where the scales are to be used.=0AYes, it 
is yours and your families life you are talking about.  Th
anks Bub for your wise input.=0A=0APete Jeffers=0A=0A=0A=0A=0A=0A=0A
-----Original Message-----=0AFrom: Bud Yerly <budyerly@msn.com>=0ATo: 
europa-list@matronics.com=0ASent: Thu, 24 Mar 2011 3:35=0ASubject: R
e: Europa-List: Weight and Balance Scales=0A=0A=0A=0AI hate to b
ut in, but weight and balance is not a sorta, kinda, maybe
 about this many pounds measurement.  We all spend hours m
aking sure our aircraft is within .1 degree and exact sweep 
and incidence and then weigh the aircraft and measure the ba
lance points with a grease pencil and a bath scale certified
 by our last physical weigh in.  =0A=0AI know calibrated s
cales are expensive, but go to your airports certified weight 
and balance professional or if you insist on doing it yourse
lf, go to the racing community and find a set of certified
 scales of the proper size and range and rent them or bo
rrow them for a day..  Load cells are best, but I must 
admit some spring types are quite accurate.  It amazes me 
that the car guys and go cart enthusiasts have superb scales
.  I have seen them for as low as $500 new.  I know 
this as I lived next door to a sprint car builder and he
 had the neatest stuff.=0A =0AUse a good level, plumb bobs, 
and tape measures and be accurate.  Follow the operators han
dbook instructions.  I recently had a plane in the shop th
at was touted as only 875 lbs, using bath scales.  The a
ctual weight was 904 and his CG was off by a half and 
inch because he used the dimensions in the book instead of 
measuring his own plane.  Luckily our little bird is tolerab
le of many things, including loading and weight and balance 
errors.  Putting a 2 X 6 between two scales can work, bu
t verify with accurate weights and get a good tare of the 
scales.  Make sure the weigh ins are repeatable and use a 
known set of weights to verify the scales range and accuracy
.  If using two scales with a beam between, verify the p
ositon of the beam and where the tire center will sit.=0A 
=0AIt costs me a couple of hours and a couple hundred buck
s for Walter Hudson (FAA Certified weight and balance tech, 
A&P and homebuilder) to come by and weigh the planes in my
 shop.  Dead on, certified, and repeatable results.=0A =0AKevi
n, I do the same thing.  I built ramps and blocks the 
exact height of the scales and of course from plumb bobs d
own the cowl line, the axles and then careful measurements t
o get my distances for the moments.  Jigs like this make 
things simple.  For the mono I must admit, to being extrem
ely lazy and use a finger to balance the wing by pushing 
up on the heavy wing and down on the light wing and aver
age the difference.  I have not found a mono more than a
 couple of pounds out of perfect balance.=0A =0ABud Yerly  
=0A =0A=0A----- Original Message ----- =0AFrom: K BURNS =0ATo: 
europa-list@matronics.com =0ASent: Sunday, March 20, 2011 2:20 PM=0A
Subject: Re: Europa-List: Weight and Balance Scales=0A=0A=0A=0AHi,=0A
 =0AOne set of scales would do with two spacer blocks unde
r the wheels same height as scale, weigh at one wheel then
 either with  jacks or 3 ramps move the scale from wheel
 to wheel , replacing with a block to keep the a/c level
 , recording your figures as you go on your balance sheet.
=0A(easier to use 3 blocks if only using one jack so you 
can lift remove scale lower on spare block then move jack 
to next wheel)=0A =0AKevin =0A=0A=0A=0AFrom: Robert Borger <rlborg
er@mac.com>=0ATo: europa-list@matronics.com=0ASent: Sunday, 20 March, 
2011 14:44:45=0ASubject: Re: Europa-List: Weight and Balance Scale
s=0A=0AMike, =0A=0A=0AI played on balances.com for a bit and o
n a 400 lb search I found a Siltec 440LB GS1 digital sca
le for $78.95.  It's a bathroom scale but three of them 
($236.85) would probably do the job as long as your aircraft
 is under 900 lbs and you are careful getting the mains 
onto the scale.=0A=0A=0A=0A=0A=0A=0A=0A=0A=0ABob Borger=0A=0A=0A=0A=0A=0A=0A
=0A=0A=0AOn Mar 20, 2011, at 1:36, DuaneFamly@aol.com wrote:=0A=0A
=0A=0A=0A=0AIn the USA, what are people using with regard to 
scales when they do their weight and balance calculations? Wha
t capacity is needed?=0A =0AMike Duane=0ARedding, California=0AEurop
a XS Conventional Gear=0A=0A=0A=0Ahref="http://www.matronics.com/Navi
gator?Europa-List"http://www.matronhref="http://forums.matronics.com"http://fo
rums.matronics.comref="http://www.matronics.com/contribution"http://www.mat
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