Do you work in Imperial or Metric?

Being an Aussie I remember going to school Monday and being told we are no longer learning inches we are now learning metric, so I use both. Especially as My lathe has imperial dials and my mill has metric. If I need to turn something on the lathe to 40mm I just convert that to 1.575" to bring it close with the dials, then use a metric mic.

I have an old V12 Jaguar and it is mostly imperial but Jaguar just threw a few metric bolts in here and there, except for my spare V12 which is all metric so I can not interchange any studs.
 
Jim Dobson said:
Do you work in Imperial or Metric?

Being an Aussie and 52 years of age I was mid school when Australia started the change over from Imperial to Metric (something that even to this day 40 years later isn't even completely instituted). Here we were one day at school learning Imperial and the next we were told to scratch that and start learning Metric. Something that even our teaches struggled with. So a lot of us around my age have always been in a bit of a twilight zone when it comes to both systems. Older people can easily work in Imperial and younger people can easily work in metric because its what they were solely taught.

Ok, after saying all the above I do find working in metric a whole lot easier, but I still work a lot in imperial as well.

I still to this day wish that I'd been taught just the one method.

What's your preference and what were you taught?
Click to expand...
Taught both, switch between as needed.
 
I'm 67, raised and schooled strictly in U.S. Customary (a new term for me). Foreign cars introduced me to metric (and Whitworth, damn Limeys). During my apprenticeship I had to translate several hundred Japanese blueprints for shop use (I don't speak or read Japanese). I am now quite comfortable in either system, though I instinctively choose inches over millimeters when designing.
 
As a chemist and a physicist, I used the metric system for fifty years. As an engineer, I have worked with both. I generally design in Imperial measure. No particular reason other than it is what I have always used. Imperial fasteners are easier to find and less expensive the metric though. My machines are equally capable of working in either system although metric threading on an Imperial lathe is more complex. I still tend to design in nice round numbers even though the CNC could care less.

An interesting challenge was designing a piece of laboratory equipment where the part contained some features that were positioned in an 8 x 12 array on 9 mm centers. The part was designed in inches but the problem came up with dimensioning. Since 9mm is equal to .35433" rounding to three decimal places would create a problem with tolerance stacking. The workaround was to use ordinate dimensioning so that each position was accurately dimensioned to within .001".

IMO, the biggest reason that we still use Imperial measure in the US is stock sizes. Think about the difficulty someone would have trying to build a metric house. It isn't much better when it comes to metal working.

In a company that I used to work for, our UK site ran out of their supply of 4" acrylic tubing. They hadn't ordered for a while and the stock had gone metric. There wasn't a workable metric size so they ended up having us order the 4" tubing here and ship it to them.

The flip side of the coin is that suppliers aren't going to stock metric stock when there isn't a serious demad for it. It's a catch 22 situation. Along similar lines was the story about why barns are painted red. The answer was that was the only color available for barn paint. Asking the paint manufacturers why they only made red paint, their answer was nobody uses anything other than red.

An industry with vertical integration like the automotive industry has it easier since they either make their own components or they order them made to their specs. and they have largely gone metric. The same is true for the scientific and medical equipment industries.
 
I do both. All my machines do Imperial, but some have a metric dial as well. I use whichever micrometer is best for the job, and all my vernier are in both anyway.

so I'd say 80% Imperial, 20% Metric.
 
I'm part of the small group which works in metric in the United States.
Most obvious difference: there's a single system of drill bits in metric. It is fantastic.

There are some difficulties in buying metric tools. I recently went looking for long-reach 3-flute ball nose end mills. Kyocera makes some in metric sizes, but the minimum purchase quantity and lead time were prohibitive. I ordered some inch sizes from McMaster. It's easy enough to put 9.525 mm into my tool table for a 3/8" diameter end mill.

I find that converting inch dimensions to metric involves less rounding or truncating than the other way around, especially when discussing tolerances.
 
99% metric these days. When I started hobby machining and welding when I was at high school, New Zealand had changed over to metric 20 years before. The machines I used in my uncle’s workshop were imperial Colchesters, second hand tooling and measuring equipment was all imperial, imperial fasteners were common and even imperial sized steel. Now anything imperial is special order and costs more. I inherited my father in laws tools which were all metric as he was a German engineer.
I can’t understand how anyone can design buildings ( at least the engineering) in imperial. I did a fire sprinkler design for the Hawaii office of my then employer. Room dimensions in feet-inches-fractions made it hard to layout and tally up dimensions. Would have been ok if it was decimal feet (23.6 feet), so I went over all the drawings, converted to SI units to do the layout and calculations, then converted back and fiddled to round numbers...
 
warrjon said:
I wonder how many will get that reference.............ooops
Click to expand...
Indeed. Either system is capable of the required accuracy. If one chooses to MIX the systems, then one is required to CONVERT accurately.:confused 3:
 
You must log in or register to reply here.
Back
Top