Any wonder why I get confused!!

Makes sense to me. We already use the metric system. Don't believe me? How many pennies in a dollar? Dimes? Quarters? That's metric in its' basic form, and we use it every day.

edw wrote:Makes sense to me. We already use the metric system. Don't believe me? How many pennies in a dollar? Dimes? Quarters? That's metric in its' basic form, and we use it every day.

I wouldn't call decimal currency metric, just because it uses decimals.  There's an awfull lot more to it than just currency.  Actually, you also use decimals when describing incomplete inches.  Rather than stating fractions of an inch, you use decimals.  We've always stated fine measurements in "thou" (thousanths of an Inch) and that is still widely used.  If we go back to the imperial system originally used, we talk in fractions.  Gauge was never really used here to my knowledge, except in fencing wire and shotguns.  Why is that?  Who knows?

Decimal Currency was introduced in Australia in 1966, well before going metric.  I guess you get to understand what you grow up with, but my confusion/frustration comes about from the fact that screw measurements in the USA use two completely different measuring systems, changing from Gauge to fractional at 1/4".  That's the subject of the article I attached.  Just seems that I'm not the only one confused by this oddity.  

There's every chance that we do have equivalent screw threads to your U.S. ones here, most likely stated as UNC or UNF, but I'm yet to find a comparison chart to point me in the right direction.  We typically used Whitworth for many years, but as the TPI measurement is the same as UNC (apart from 1/2" for some odd reason, which is one thread coarser), we go with UNC now.  Some of my older Commonwealth built engines/machinery also use B.A. screws.  Now that gets confusing.