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photocopied shrink ruler ; was: re: calculating shrinkage

updated sun 6 jul 03

 

Lee Love on sat 5 jul 03


----- Original Message -----
From: "Snail Scott"

> LONG RULERS:
>
> After determining the shrinkage, some people make
> a 'long ruler'. This is a stick of wood or a metal

Another way to do it, (especially if you have difficulty drawing straight
lines), is to take a normal ruler to the xerox machine or scanner and change the
percentage of the copy to match your shrinkage. Below is a list of shrinkage
percentages and percentage of enlargement. You can probably round off to the
nearest whole number, but I take it two decimal points:

10% = 111.11% enlargement
11% = 112.36
12% = 113.64
13% = 114.94
14% = 116.28

You can use the example below for 10% to figure out any percentage (just
subtract the shrinkage from 100%
~~~~~~~~~~~~~~~~
if 90/100 = 100/x
therefore 90x = (100 X 100)
therefore x = (100 X 100)/90
therefore x = 10000/90
therefore x = 111.11

90% of 111.11 equals 99.99
~~~~~~~~~~~~~~~~~~

Really, all you are doing is dividing 10000 (100 X 100) by the shrinkage like
so:

for 10% 10000 divided by 90
for 11% 10000 divided by 89

and so forth.

I was in the middle of my apprenticeship when this first came up and
didn't have time to even think about it. Now, I have more time. :^)

Laminate the photocopy to make it last.


~~~~~~~Lee In Mashiko, Japan http://hachiko.com ~~~~~~~~~~~~~~~~~~
* *
* They teach in academies far too many things, and far *
* too much that is useless. *
~~~~~~~~~~ Johann Wolfgang von Goethe~~~~~~~~~~~~~~~~~~~~~~