I don't understand the 1/6, 1/3, 4/5 things.. And don't know how to conver it..
I understand you wanting to work n metric and that is fine.
1) metric is easier you have to think and remember less.
2) I expect you grew up with metric and that is what you are used to.
3) I expect your machine tool dials are calibrated in metric as are you measuring tools.
I on on the other hand grew up with am used to and am tooled in imperial measurements.
converting from imperial measurements is rather easy but it can get tedious.
there are various approaches to your dilemma.
1) simply work off metric plans. There are many out there both designed as metric plans and ones converted by someone else from imperial to metric.
2) perform a scaled conversion if you let 1/16 of an inch = 1mm you will get a model aprox 66% the size of the original but it will come out in even millimeter. Or you can make 1/32 " = 1 mm and end up with a model aprox 125% of the original but again have even MM dimensions.
3) conversion charts such as this one:
http://mdmetric.com/tech/cvtcht.htm
the chart gives fractional inches decimal inches and mm side by side .
4) metric to inch /inch to metric converter. These are available on line or can be downloaded and installed in your computer. The above link has such a converter.
5) last but not least you can do (Uhg) the math. simply divide the top number of a fraction (the numerator) by the bottom number( the denominator) then multiply by the conversion factor.
I know from memory 1/16" =.0625 " 1/8 =.125 ", 1/4 =.250 , 1/2 =.500 3/4 =.750 .........
now simply multiply your decimal number by 25.4 and you now have the dimension in millimeters.
I do not know about your part of the world but here in the USA calculators are available virtually at any corner drug store ,discount store etc.
A good college level programmable calculator that will do calculus and differential equations will run something like $ 150. But basic scientific calculators can be had in the $10 -$15 range even dollar stores Cary varied models of calculators even scientific calculators for YES $1.00 USD so there is from my point of view nor reason you can not convert. I admit you may not want to take the time and that is your choice.
My basic school education as well as my machining training included basic math lessons in working with fractions and decimals and converting from one to another. And I also learned about the metric system and have a working knowledge of it.
Tin
