All my life I have been working in metric totally oblivious to the fact that the measure of length that I call a "mil" might not be the same as what you call a "mil"...
New subscriber here. Love the channel. I’m in the UK and did know that a mil is a thousandth of an inch. As you say, the term mil is now commonly misused to mean 1mm in the UK. I’m sure that’s set to continue over time as there are fewer and fewer of us left who grew up before metric became commonplace. It reminds me of other pre-metric units of measurement like chains, links, rods, pole, perch, furlongs and fathoms, etc - though I often forget how many inches or yards some of them actually represent 😂. Thanks again for the video.
Welcome to the channel! The old measurements have a certain charm to them but you're right, trying to remember the breakdown like how many feet by how many feet an acre is (one chain by one furlong) 😂
Having worked in both finance and machine shops in the US, the only place I see “mil” used to mean 1/1000th of an inch is plastic sheeting. Trash bags and painting drop cloths are labeled with their thickness in mil. I’ve never heard mil to describe 1/1000th of a dollar. We would speak in fractional and decimal cents, “half a cent”, “point oh four five one cents”. In the machine shop we use “thou”. I suspect most Americans think of millimeters or another si unit when they hear “mil”.
In my experience 'mil' IS used as a measurement, and I've generally seen it when talking about plastic sheeting (a.k.a. "20 mil poly sheeting" for waterproofing). In machining, 'thou' is often used for thousandths of an inch.
I don't recall hearing it in many other contexts, but this one is common and consistent. Plastic tarps and plastic bags. I think most will list their thickness in mil.
The issues with imperial are that you need an extra digit of precision to be able to accurately work with it, and most ameican machines don't have that for their own systems either, so the equipment and machines they work with are manufactured with more slop. Even your digital gauges when showing imperial are converting from Metric, and the math inside says f that, so there's quickly mistakes accumulating xD
In mechanical engineering and machineine shop applications in North America a mill is still .001 (inches - lack a leading zero) as apposed to 0.01 (mm have a leading zero). The first general note would also state that all dimensions are inches and millimeters are in parentheses and for reference only, or the reciprical note if the design in "hard" metric and "soft" US Customary/Imperial or something to that affect.
As a European machinist moved to the US, yes one mil is .001 inches and you find it in the dials of most old machines (new ones frequently have double dials with metric equivalents too). Two advantages of mils: allows using the old Imperial measuring system in a decimal format instead of stupid fractions (solves a self-inflicted problem) and, something I learned to appreciate with time, gives a good feeling of the quality of a machining job (high precision +/- 1 mil, regular work +/- 2-4 mils, home shop +/- 5-10 mils.
Spot on! In the UK we call them thous, and like a lot of imperial measurements they make a lot more sense than metric. Without risk of starting a metric vs imperial war, metric is very convenient but like you say working in 1 thou/mil 2 thou, 5 thou etc. is so much more human. Must admit I tend to flit between the two even though we've been metric for 50 years or more.
I came across mil as being a thou about 30 or 40 years ago from an old timer, but brilliant, machinist. Mil is also short for ml or millilitres, exactly the same as a cc. Depends on whether you were brought up on MKS, CGS, SI system or whatever they use these days.
In the electronics industry a mil is still often and commonly used today. It's used to define PCB trace width, and most commonly it's used for BGA component definition, for ball pitch and diameter. So if I said that I had a component with 20 mil balls and 40 mil pitch, that's all in thousandsths of an inch. In most online machinist forums I've seen people use thou for thousandths of an inch. I don't like saying mil for millimeters simply because of the confusion. Of course all these problems could be solved if silly countries like America got in line with 99% of the rest of the world and used metric.
In the US we usually abbreviate the word "thousandth of an inch" to "thou". So, 5 thousandth of an inch would be called 5 mils, or 5 thou. BTW, Mille means thousand, not million (so it does make sense) 😉 Ciao, Marco.
Here in the US it’s most common that mils are millimeters as a layman’s term. If one works in Engineering, Machining, or some technical industries, then mils are known as 1/1000 of an inch.
I have always said THOU for 1 thousands of... That is the first I heard that... I was looking for a video to explain to me Millradian is not a metric measurement for scope dialing (just an fyi)
Milliradians are really interesting with mildot scopes. Crazy how 1 milliradian is 1/1000 of a radian, and a circle is 2π radians. And on a scope it conveniently works out to 1 mil is 10cm at 100 metres.
And in the UK we would tend to say Thous. Interesting that many Americans say the full word and dont shorten it, at least the ones I have seen here on RUclips.
They have circular mil too! A circle with a diamter of a thou, or 5.067×10−4 mm2. I shit you not. (and the whole subject of using the centimeter as an engineering unit is best left alone)
Seven words that make algorithms love You.
New subscriber here. Love the channel. I’m in the UK and did know that a mil is a thousandth of an inch. As you say, the term mil is now commonly misused to mean 1mm in the UK. I’m sure that’s set to continue over time as there are fewer and fewer of us left who grew up before metric became commonplace. It reminds me of other pre-metric units of measurement like chains, links, rods, pole, perch, furlongs and fathoms, etc - though I often forget how many inches or yards some of them actually represent 😂. Thanks again for the video.
Welcome to the channel! The old measurements have a certain charm to them but you're right, trying to remember the breakdown like how many feet by how many feet an acre is (one chain by one furlong) 😂
Sarchasm, that yawning gap between my intellect and your level of understanding.... need a t-shirt with that on it. 👍
Having worked in both finance and machine shops in the US, the only place I see “mil” used to mean 1/1000th of an inch is plastic sheeting. Trash bags and painting drop cloths are labeled with their thickness in mil. I’ve never heard mil to describe 1/1000th of a dollar. We would speak in fractional and decimal cents, “half a cent”, “point oh four five one cents”. In the machine shop we use “thou”.
I suspect most Americans think of millimeters or another si unit when they hear “mil”.
Thanks for the info - much appreciated 👍
there's also the horrific kcmil used for wires.
I learned this a decade ago working with yanks on PCBs, got them to switch to thou :-)
This is only a verbal issue, typically.
In my experience 'mil' IS used as a measurement, and I've generally seen it when talking about plastic sheeting (a.k.a. "20 mil poly sheeting" for waterproofing). In machining, 'thou' is often used for thousandths of an inch.
I don't recall hearing it in many other contexts, but this one is common and consistent. Plastic tarps and plastic bags. I think most will list their thickness in mil.
The issues with imperial are that you need an extra digit of precision to be able to accurately work with it, and most ameican machines don't have that for their own systems either, so the equipment and machines they work with are manufactured with more slop. Even your digital gauges when showing imperial are converting from Metric, and the math inside says f that, so there's quickly mistakes accumulating xD
In mechanical engineering and machineine shop applications in North America a mill is still .001 (inches - lack a leading zero) as apposed to 0.01 (mm have a leading zero). The first general note would also state that all dimensions are inches and millimeters are in parentheses and for reference only, or the reciprical note if the design in "hard" metric and "soft" US Customary/Imperial or something to that affect.
As a European machinist moved to the US, yes one mil is .001 inches and you find it in the dials of most old machines (new ones frequently have double dials with metric equivalents too). Two advantages of mils: allows using the old Imperial measuring system in a decimal format instead of stupid fractions (solves a self-inflicted problem) and, something I learned to appreciate with time, gives a good feeling of the quality of a machining job (high precision +/- 1 mil, regular work +/- 2-4 mils, home shop +/- 5-10 mils.
Spot on! In the UK we call them thous, and like a lot of imperial measurements they make a lot more sense than metric. Without risk of starting a metric vs imperial war, metric is very convenient but like you say working in 1 thou/mil 2 thou, 5 thou etc. is so much more human. Must admit I tend to flit between the two even though we've been metric for 50 years or more.
A mill is not a mill, unless it's grinding grain into flour ! ... lol
I came across mil as being a thou about 30 or 40 years ago from an old timer, but brilliant, machinist.
Mil is also short for ml or millilitres, exactly the same as a cc. Depends on whether you were brought up on MKS, CGS, SI system or whatever they use these days.
I heard it in use of tickness in tin sheets of plastic for example here in US.
In the electronics industry a mil is still often and commonly used today. It's used to define PCB trace width, and most commonly it's used for BGA component definition, for ball pitch and diameter. So if I said that I had a component with 20 mil balls and 40 mil pitch, that's all in thousandsths of an inch.
In most online machinist forums I've seen people use thou for thousandths of an inch. I don't like saying mil for millimeters simply because of the confusion.
Of course all these problems could be solved if silly countries like America got in line with 99% of the rest of the world and used metric.
say thou instead, then nobody will mix up.
So say thou though?
In the US we usually abbreviate the word "thousandth of an inch" to "thou". So, 5 thousandth of an inch would be called 5 mils, or 5 thou. BTW, Mille means thousand, not million (so it does make sense) 😉 Ciao, Marco.
the imperial version is used in pcb trace thicknesses. and mil is just a thousandth
Here in the US it’s most common that mils are millimeters as a layman’s term. If one works in Engineering, Machining, or some technical industries, then mils are known as 1/1000 of an inch.
I have always said THOU for 1 thousands of... That is the first I heard that... I was looking for a video to explain to me Millradian is not a metric measurement for scope dialing (just an fyi)
Milliradians are really interesting with mildot scopes. Crazy how 1 milliradian is 1/1000 of a radian, and a circle is 2π radians. And on a scope it conveniently works out to 1 mil is 10cm at 100 metres.
I hear machinists in the US usually say "thousandths".
And in the UK we would tend to say Thous. Interesting that many Americans say the full word and dont shorten it, at least the ones I have seen here on RUclips.
thou rhymes with cow
you still see mils on some things though, specifically thin plastics are often measured in mils (trash bags, contractor bags, marine heat shrink)
They have circular mil too! A circle with a diamter of a thou, or 5.067×10−4 mm2.
I shit you not.
(and the whole subject of using the centimeter as an engineering unit is best left alone)
As apprentices I reckon we would have been punished for working in centimetres 😂
@radboogie well it certainly would have kept you in line 😂
in USA mil is colloquially used for paint thickness or sheet thickness
Thanks for the info 👍
Calling millimetres "mils" is nonstandard. If you want to use the metric system, then use the metric system as it is, renaming is counterproductive.