Where can you buy a 30g scale for $25 ?

>> On May 28, 2013, at 10:23 AM,
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>>  Pefhany wrote:
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> At 01:41 AM 26/05/2013, you wrote:
>> I was weighing pills and tried this setup to improve the scale sensitivi=
ty.
>> See photos here =3D=3D>=20
>> https://plus.google.com/u/0/photos/102396176247280453443/albums/58821542=
51101853345?hl=3Den
>> Max is 5000g says the scale legend.
>> I put a hinge at one end of a bar and clamped it to a book.
>> I put a styrofoam cup at the other end of the bar.
>> I used a marker as a pivot point.   The bar does not touch anything else=
..
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>> #1  I used the tare function to zero the scale while the cup was at the =
end.
>> #2  I measured in 9 pills and weighed them. ( 97 grams )
>> #3  I added all the pills ( 90 ) and weighed them.  ( 969 grams )
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>> 969 /97 * 10 =3D .999   That was the best result I had.  My worst was=20
>> 1.28 when I was measuring smaller pills.
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>> What would be sources of error ?
>> #1       the scale     I did not use the calibrate function since I=20
>> was doing ratio-metric comparisons.  Maybe cal would have improved thing=
s.
>> #2      pressing on the hinge where it was clamped to the book=20
>> changed the amount measured.  I do not understand this.  I waited=20
>> for the scale to settle down and it was still showing a reading as=20
>> much as 5% off.
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>> As Napoleon Dynamite would say...... * You idiot*
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>> Gus                         keywords  99centech  99scale   99pills
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> You can buy a 30g full scale digital scale for under $25 (0.001g resoluti=
on).
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> Cheap scales are going to have friction/hysteresis and nonlinearity. Expe=
nsive
> ones will too, but it will tend to be less. ;-)
> As others have said, it's hard to make a scale that's accurate over a wid=
e
> range, and about impossible to do it for cheap.
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> 0.1% of full scale is not bad for a Harbor Fright product.
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> --sp
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> --=20
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