Stephani Stephenson on sat 17 sep 11
there's a bit of a misstep in the middle of the clip ,with regard to maki=
=3D
ng
the shrink rule, specifically enlarging the paper ruler via computer or c=
=3D
opier.
on the clip I am using clay that shrinks 8% as an example and showing ho=
=3D
w
to make a shrink rule for 8% shrinkage clay.
i make a paper ruler then enlarge it on a computer or copier, before
transcribing it onto a dry wall square.
i say "I enlarge it by 8% ( or 108% on the computer or printer) for cla=
=3D
y
that shrinks 8%"
what you REALLY need to do for accuracy is first
Subtract the the shrinkage (in this case 8%) from 100 which equals 92.
then divide 8 by 92 which gives you 8.695,or 8.7%
so, in this case, on your computer or photocopier you need to enlarge it=
=3D
by
8.7 percent, or 108.7% ( or 109%)
that is because 8.7 % of the smaller number is actually 8% of the larger
number and when we are talking shrinkage we are starting from the larger =
=3D
number.
I knew this, but forgot it during the taping.=3D20
the DVD is still in edit but i wanted to point it out for anyone watchin=
=3D
g
the clip. it is a small ,but important difference, especially when worki=
=3D
ng
large or when working with higher shrinkage clay. It should be righted in=
=3D
the finished product.
Snail Scott on sun 18 sep 11
On Sep 17, 2011, at 4:00 PM, Stephani Stephenson wrote:
> ...i say "I enlarge it by 8% ( or 108% on the computer or printer) =3D
for clay
> that shrinks 8%"...
> what you REALLY need to do for accuracy is first
> Subtract the the shrinkage (in this case 8%) from 100 which equals =3D
92.
> then divide 8 by 92 which gives you 8.695,or 8.7%...
Good thing you caught that! Everyone clear now?
This can be hard to get your head around when =3D20
dealing with our relatively low shrinkages. It's=3D20
not immediately obvious at a glance why simply=3D20
increasing by the shrinkage amount won't work.
Instead, think about bigger, easier numbers. Let's=3D20
say you invested $1000 in the stock market and=3D20
lost half your investment: you now have $500, or a=3D20
50% shrinkage. How much will the stock market=3D20
have to rise for you to regain your lost money? If=3D20
the market increases by 50%, how much do you=3D20
end up with? 50% of 500 isn't 500, of course, it's 250,=3D20
for a total value of $750. A 50% increase doesn't=3D20
offset a 50% loss, it takes 100% increase to offset=3D20
a 50% loss. And so on.
That's why you can't just add the percentage of=3D20
shrinkage onto 100% to get the new measurement.
Hope this helps.=3D20
-Snail=3D
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