who has gone metric?

My lathe is imperial, my mill metric. I have no DRO on either. I work in metric when machining, only resorting to imperial when I have to accurately turn something, but simply because my lathe is imperial and I work off the hand wheels.

The railway is all imperial. Not UNC/UNF... Noooo. Whitworth. Some of it pre-war, some of it post war (different head sizes for thread size) and bastard pipe threads that the rest of the world has long forgotten. Sometimes some joker has turned a Whitworth bolt from a piece of metric hex stock. And some threads on the stays in the boiler have special taps that run an 11tpi whit thread from 7/16" right to 11/16.

So I flit between the two. If measuring something roughly, I often do so in whole or half inches. Anything more precise than that and I'm going metric - fractions are just too silly to read on a tape measure. Whoever decided to measure sub inches in fractions rather decimal needs a stern talking to and time to think about what they've done! Lol.
I'm a metric man, but the world refuses to let go of archaic, awkward standards. Why we still have miles on road signs and speed limits is beyond me too.

Chains and rods, anyone?
 
Everything is a number that is measurable down to a acceptable tolerance of about .001 inches, metric works with those numbers also. I use both, but most my machines are in US inches IE .001. DRO's and digital calipers do the conversions for me at the press of a button. I will admit my Chinese lathe has holes drilled and tapped with US fasteners, and my Clausing mill has holes drilled and tapped for Metric fasteners of the DRO install. Its mix and match in my shop. I do most of my work in inches, but I have built a few projects that are all in metric.
 
I’ll (mostly) work happily in either imperial or metric lengths.

I have three annoyances:
- Fractions (if the fraction arithmetic gets too annoying, I’ll tend to switch to mm’s- though I did just put a dedicated fractional calculator on my phone which so far as soothed this annoyance).
- 1/8” is too similar to 1/10” (so I no longer use the 10th scale on my imperial rulers).
- 1mm is too hard to read (now...).

I tend to use:
- Meters for distances larger than about 8’
- Feet and/or inches for distances larger than about 15mm.
- mm’s for distances larger than 1mm.
- new glasses for distances greater than zero (I’m joking here of course...)
 
I'm units-ambivalent. After living in Europe for over 10 years, I just don't get hung up anymore. Conversions work, DROs switch units with the push of a button, and the more interesting machines out there have dual-scale handwheels. Today feels like 28 degrees C. I lose money every time the exchange rate shifts the wrong way. Liters just about equal quarts. Metric units are based on universal constants, imperial units are based on the length of a king's foot or how much ale he could drink in an hour. Okay, maybe one system makes more sense than the other...
 
Ulma Doctor said:
i need to have both types of measurement and use whatever is necessary for the task.
over the years i have used metric bolts to replace uss and sae bolts where a blind hole was stripped out of the casting/part.
a M4 is your friend when you have a stripped out 10-32, a 10-32 when you need to repair a M3
a M7 works well if a 1/4-20 gets fouled up, a 1/4-20 to repair an M5
a M10 will work for a 3/8-16 gone bad, a 3/8-16 will take care of an M8 or a 5/16-18 that have been stripped out

i have used heli coils, but i use then only as a last resort.
I like Keen-serts the best, but unfortunately you need a lot of surrounding material to install the insert.
if it absolutely,positively,has to work right now, i'll drill,tap and GO!!

Most of the machines i work on are made in Europe, I've had to become very comfortable with metric measurements and fasteners
Click to expand...


I so agree with you and have found a little helpful chart that allows me to pick smidgen smaller or a bit larger by bouncing between systems:
 

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Growing up Imperial and the switch over to Metrickery taking place when I started taking exams and had to work in both, then entering the workforce where I had to deal with both systems my biggest bug bear is talking to people in supply industries who apparently have never heard of the Imperial system. Example was an import salesman with English as a 4th or 5th language who was "A master plumber",(no such thing in this country),hand me 10 mm bolt when I asked for a 3/8" BSPT bung because " 3/8" and 10 mm are the same thing".
Their is still a huge amount of Imperial machinery in the world,(long may it stay),and sometimes fractions are just easier to work with. Having fractions and decimals to work with makes life easy.
 
I use both but I don’t work on cars anymore so I don’t use metric much.
I’m 63 and stubborn, set in my ways.
 
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