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Incorrect Calculation of an Imperial Dimension

peter_morrispeter_morris Member Posts: 43 ✭✭
I'm currently drawing the headstock of a very old lathe (simply because I can!).  I want the dimensions to show as "Inches Fractions", but when I do the figure is incorrect.  When I use either inches or metric the dimension is correct.  For example the conversion from 15.88mm results in 3/4 when it should be 5/8.  I suspect this is a flaw in the conversion routine, but if you're going to offer Inches Fractions then they absolutely must be correct - a tolerance of a 1/4" is dreadful.  The resolution should be at least 1/128" and probably less.

Ohh, I've just found the problem - the default setting of the precision was too course.  The situation is now much improved as I found I could select a precision of 1/64", but I would propose that the maximum precision is still too course, as mentioned above 1/128 would be better.

(I've left the first part of this question as I wrote it as this may be of use to other users).

Best Answer


  • billy2billy2 Member, OS Professional, Mentor, Developers, User Group Leader Posts: 1,406 PRO
    Another good reason to switch to mm.

    quick, what's 7/64th? or 17/128th?

    I need to get back to work, as I'm not making any friends today.....

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