A .41 magnum is a .410 diameter, but a 44 magnum is a .429.....only .019 bigger than the .41. It doesn't seem like much, but there is a difference in shooting them. Confusing, ain't it?
As a machinist I was stunned that we would have to get prints for parts in metric sometimes. Some of the math required to program a CNC machine is pretty complicated. Metric generally takes more numbers and simply because you have to type them in setup takes longer. Not to mention the added complication of having to use a calculator to add, subtract, calculate an angle. Add to that having to put mm at the end! Stupid. Especially after you do that you have to convert it to inch anyway! The vast amount of precision measuring tools are in inch almost everywhere so I know there are people out there in Europe converting inch to metric, good screwm! The only people that think the metric system is even ok never used the inch to any degree.
All just complete nonsense. The reason you think the imperial system is easier is simply because that's what you're accustomed to and how you relate to measures. I'm a machinist. I work for one of the top 3 CNC machine tool manufacturers. I've worked in both metric and imperial shops in the past and can very easily converse in either units, and in fact am required to because we have both imperial and metric customers. Metric is much easier because everything is in increments of 10. I know a ton of people in industry and I'm not exaggerating when I say that every single person I know who has worked for years in shops using both units prefers the metric system. The only reason you're finding conversions cumbersome is because you're doing conversions between the two systems in the first place. If you were to work in a shop that is entirely metric for just a short time, working from part prints that were designed in metric units, the math is no more "difficult" because you're not doing conversions. When the default units are specified in mm on a part print, then no, you don't need "to put mm at the end" of anything. That's what drawing title blocks are for. You also don't "put mm at the end" in any CNC program just as you don't put "inch" at the end of imperial numbers. You define that in the units parameter on the machine control once. Metric doesn't "generally take(s) more numbers" necessarily, depending on the precision you're working with. Sure, metric requires another number or two on the left side of the decimal, but fewer numbers on the right of the decimal compared to inches. If you're talking about part prints and CNC programming, you're dealing with only one unit designator - millimeters. If parts are designed in metric to begin with, then the designer typically used dimensions in whole numbers, numbers with only 1 decimal place, and seldom to more than 2 decimal places, because the units used were always in metric to begin with, not converted over from inch. The exception is if the part in question was designed in mm but intended to mate to another part designed in imperial units.
As for programming, if you're manually fat-fingering in programs at the machine control or typing up a text file and uploading to the control, then you're either doing some really simple programming, you're only doing minor program editing, or your shop is behind the times and too cheap to invest in some good CAM software. If you have a good CAM software package, it doesn't make a damn whether you're working in metric or imperial units and neither have any influence on programming time.
If you truly believe "the vast amount of precision measuring tools are in inch almost everywhere," then you've been hiding under a rock for a long time, and you certainly haven't been to IMTS lately. The exact opposite is true. The "vast amount" of everything in the manufacturing world, be it precision measuring tools, cutting tools, fasteners, etc are in metric because that is what the majority of the world works in. Open up a Sandvik catalog (you know, the world's largest cutting tools manufacturer) and compare the amount of offerings in metric vs imperial sizes. Ironically, every fastener on the CNC machine you're using every day to type in imperial units, and every part dimension on said machine is in metric dimensions. Now I totally believe the "vast amount" of stuff at your local Groves Industrial, MSC, Fastenal, etc are in imperial units. That's only because the shops local to you are predominantly working in inches, especially in oil and gas country, where shops are still clinging to imperial units with white knuckles. So, your local industrial supply stores are stocking what they will sell. In areas of the country where automotive and aerospace manufacturing dominates, metric is most common by far because all of the finished product is either predominantly or entirely in metric. In most manufacturing segments, metric rules...even in the United States.
I’ve been following this thread since inception and have just had it shake my head at some of the stuff I’ve seen. RIFLE DUDE says it well. I’m a journeyman tool and die maker, have been working in both systems since the mid-70’s. Metric is far superior and much more logical.
The big mistake made by US industry when switching to metric was the agenda was in trying to teach everyone how to do conversions, rather than just going hard metric. That was all so complicated, because of the absurd complication of the imperial system, that your average industrial worker ran out of brain cells trying to figure it out.
One thing that hasn’t been mentioned here is the elegant relationship between everything in metric. One cubic centimeter (one milliliter) of water weighs one gram. Thus one liter of water is one kilogram. One calorie raises one gram of water one degree centigrade. Everything else fits into this model. Think of how easy it is to solve a lot of engineering problems.
When I read that one flaw of the metric system was no provision for fractions I figured we’d never get this resolved.
I'm sorry but this whole conversation just reminds me of this.
“There are three things all wise men fear: the sea in storm, a night with no moon, and the anger of a gentle man.” ― Patrick Rothfuss, The Wise Man's Fear
As a machinist I was stunned that we would have to get prints for parts in metric sometimes. Some of the math required to program a CNC machine is pretty complicated. Metric generally takes more numbers and simply because you have to type them in setup takes longer. Not to mention the added complication of having to use a calculator to add, subtract, calculate an angle. Add to that having to put mm at the end! Stupid. Especially after you do that you have to convert it to inch anyway! The vast amount of precision measuring tools are in inch almost everywhere so I know there are people out there in Europe converting inch to metric, good screwm! The only people that think the metric system is even ok never used the inch to any degree.
All just complete nonsense. The reason you think the imperial system is easier is simply because that's what you're accustomed to and how you relate to measures. I'm a machinist. I work for one of the top 3 CNC machine tool manufacturers. I've worked in both metric and imperial shops in the past and can very easily converse in either units, and in fact am required to because we have both imperial and metric customers. Metric is much easier because everything is in increments of 10. I know a ton of people in industry and I'm not exaggerating when I say that every single person I know who has worked for years in shops using both units prefers the metric system.
What country do you live in? I have exactly the opposite reaction from the programmers and machinists I have known. In fact I could call and ask at least ten people and bet not one would say they prefer metric. By the way the inch works off of 10 also. Of course I only have 40 years of working in machine shops, job shops, Aerospace and oilfield.
The only reason you're finding conversions cumbersome is because you're doing conversions between the two systems in the first place. If you were to work in a shop that is entirely metric for just a short time, working from part prints that were designed in metric units, the math is no more "difficult" because you're not doing conversions.
Funny but the conversion factor is not the point actually it is the added numbers that make for much longer programs that are the annoyance. If you worked in a shop that only ran prints based on the inch you would find it easier simply because the inch itself is more useful than the millimeter or the centimeter. How you could not see this is beyond logic.
When the default units are specified in mm on a part print, then no, you don't need "to put mm at the end" of anything. That's what drawing title blocks are for. You also don't "put mm at the end" in any CNC program just as you don't put "inch" at the end of imperial numbers.
I never said that in a program I put mm or cm anywhere in the program using modern machines though there are instances where you have to do it, not in a program presently though it was necessary in some of the older CNC machines. Today you just put in G21 when running a metric program instead of the G20 for inch. Surface speed is also calculated differently. The difficulty is the added numbers required to make a metric program. The added figures/numbers are the complaint and they make finding the problem with the program more time consuming.
You define that in the units parameter on the machine control once. Metric doesn't "generally take(s) more numbers" necessarily, depending on the precision you're working with. Sure, metric requires another number or two on the left side of the decimal, but fewer numbers on the right of the decimal compared to inches. If you're talking about part prints and CNC programming, you're dealing with only one unit designator - millimeters. If parts are designed in metric to begin with, then the designer typically used dimensions in whole numbers, numbers with only 1 decimal place, and seldom to more than 2 decimal places, because the units used were always in metric to begin with, not converted over from inch.
This was not my experience at Bell Helicopter! And we received many prints in metric because we supplied parts all over the world.
The exception is if the part in question was designed in mm but intended to mate to another part designed in imperial units.
Yes!
As for programming, if you're manually fat-fingering in programs at the machine control or typing up a text file and uploading to the control, then you're either doing some really simple programming, you're only doing minor program editing, or your shop is behind the times and too cheap to invest in some good CAM software. If you have a good CAM software package, it doesn't make a damn whether you're working in metric or imperial units and neither have any influence on programming time.
When I first started running CNC lathes we floor programmed every part right off the print. Many of them were not simple at all and required hours in front of the machine punching in numbers and wearing out calculators. Mills of course are a different game altogether though we often wrote simple programs faster that the programmers running their CAD software could get them out.
Typically anymore the vast amount of time standing in front of the machines is editing/correcting CAD programs, not made easier by metric in any sense of the word. Second why do the identical programs written in metric have 25% more lines? Especially if you are writing in a .005 radius at every edge.
If you truly believe "the vast amount of precision measuring tools are in inch almost everywhere," then you've been hiding under a rock for a long time, and you certainly haven't been to IMTS lately. The exact opposite is true. The "vast amount" of everything in the manufacturing world, be it precision measuring tools, cutting tools, fasteners, etc are in metric because that is what the majority of the world works in. Open up a Sandvik catalog (you know, the world's largest cutting tools manufacturer) and compare the amount of offerings in metric vs imperial sizes. Ironically, every fastener on the CNC machine you're using every day to type in imperial units, and every part dimension on said machine is in metric dimensions. Now I totally believe the "vast amount" of stuff at your local Groves Industrial, MSC, Fastenal, etc are in imperial units. That's only because the shops local to you are predominantly working in inches, especially in oil and gas country, where shops are still clinging to imperial units with white knuckles. So, your local industrial supply stores are stocking what they will sell. In areas of the country where automotive and aerospace manufacturing dominates, metric is most common by far because all of the finished product is either predominantly or entirely in metric. In most manufacturing segments, metric rules...even in the United States.
At Bell Helicopter, Boeing and Lockheed the inch rules period. and yes the machines are predominantly built metric though the fasteners that hold the Sandvic inserts in are still loosened and tightened with inch fractional allen wrenches but torx are metric and the holders themselves use metric allen wrenches. That said you will need the 1/4 inch allen somewhere on every machine other than Okuma.
I’ve been following this thread since inception and have just had it shake my head at some of the stuff I’ve seen. RIFLE DUDE says it well. I’m a journeyman tool and die maker, have been working in both systems since the mid-70’s. Metric is far superior and much more logical.
The big mistake made by US industry when switching to metric was the agenda was in trying to teach everyone how to do conversions, rather than just going hard metric. That was all so complicated, because of the absurd complication of the imperial system, that your average industrial worker ran out of brain cells trying to figure it out.
One thing that hasn’t been mentioned here is the elegant relationship between everything in metric. One cubic centimeter (one milliliter) of water weighs one gram. Thus one liter of water is one kilogram. One calorie raises one gram of water one degree centigrade. Everything else fits into this model. Think of how easy it is to solve a lot of engineering problems.
When I read that one flaw of the metric system was no provision for fractions I figured we’d never get this resolved.
So fractions are not useful and mean nothing? A pound is not a useful measurement? The inch itself is not a useful measurement that has no equal in metric? Resolved? Journeyman tool and die maker? You might as well vote democrat for all the sense your making.
Fractions aren't needed in the metric system, e.g. 250g is 250g, 982g is 982g, 72cm is 72cm, 1.6m is 1.6m etc. I was schooled for the most part in the imperial system but we went metric in 1967.
I like to call my trout in pounds out of habit and a lot of us older guys still do. Besides an 8lb rainbow sounds bigger than a 3.628 kgs rainbow.
"The 257 Roberts, some people like to call it the “.257 Bob.” I think these people should be hung in trees where crows can peck at them." - David Petzal
Rict300, Your objection of the metric system is based on the fact you grew up with the imperial system, that's what you were taught, what you used for many years, what you relate to in your everyday life, and what you think in when dealing with units of measure of everything. It's understandable that you find something contrary to a system you've used your whole life to be cumbersome. It's human nature to reject that which runs counter to our experiences, is new...change in general. All these folks who you say agree with you on the superiority of the imperial system probably have similar experiences as you, and were never placed in an environment where they had to work in metric units exclusively for sufficient time that it became second nature to them. I deal with customers across all of North America, and I assure you, your experience isn't anywhere close to universal. Everyone who I interact with who have worked in manufacturing facilities that both use imperial and metric exclusively (not switching back and forth between the two systems) end up preferring metric. They may have been old school and arrived at that point kicking and screaming, but arrive at that point they did. If you don't believe me, I'm cool with that. If you have a different opinion than me, I'm cool with that too. You're entitled to your opinions, but many of your assertions are just factually incorrect. I live and work in Texas just as you do, but working for a CNC machine tool manufacturer, I'm pretty sure I interact with a broader customer base who manufacture a broader range of products than you do. Our customers cover all industries all across North America, and we routinely help them develop their processes used on our machines. I was also a cutting tool, gage and fixture designer for many years, and I've made custom cutting tools for many of these companies.
If you're spending the vast amount of your programming time standing at the machine control, then you obviously aren't using one of the better CAM software packages (MasterCam, Esprit, GibbsCam, EdgeCam, etc) or your parts lack sufficient complexity to make programming with CAM software viable. If you're starting out your programming with 3d CAD models of your parts, importing them into CAM software, and you have a good, proven post for your machine, then it doesn't make a damn what units you're working in with respect to programming time. That you insist otherwise indicates that you're behind the times on technology. I've done lots of programming in both units of measure. Programming in metric doesn't necessarily take any more time or consume more lines of code than programming in inch, and feeds and speeds are no more difficult to calculate in mm or meters/minute vs in or ft/min or mm/rev vs in/rev. It's all a matter of what you get used to using and what you're comfortable with.
I don't know what point you're continually trying to make with regards to the inch being expressed in increments of 10. Yeah, in the machining world you often work in tenths and thousandths of an inch. So what? That's not the point. The imperial system is made up of a hodgepodge of units that have random, inconsistent relations to each other. 12 inches in a foot...3 feet in a yard...5280 feet in a mile...231 cu/in in a gallon, 8 pints to a gallon, etc. Numbers all over the place. In the metric system, EVERY unit is expressed in increments of 10 to all other measures across the whole system...10 mm to a cm, 100 cm to a meter, 1000 M to a KM, etc. Even if one is completely entrenched in the imperial system, how anyone can't see the inherent superiority and simplicity of a system that relates all measures to each other in increments of 10 is mind-boggling.
Yes, Bell Helicopter, Lockheed Martin, and Boeing still use imperial units, but not across the board, and that's beginning to change as they pursue international contracts and work with international partners and the military. The US military went completely to metric units a long time ago. Bell Helicopter now uses primarily metric units in the V22 Osprey program. Following a disastrous, expensive loss of the Mars Orbiter due to a calculation error where NASA was working in metric and Lockheed was working in imperial units, Lockheed began converting over to metric in their space-related projects. They also work in metric on projects where they partner with contractors and governments overseas. And I don't even want to get started on the mind-numbing stupidity, inefficiency, and waste at some of those defense-related companies due to the difficulty in making process changes and conflicts with the unions which cause them to still use a lot of 1970's and 80's technology tooling and equipment. Many US manufacturers have stuck with the imperial system simply due to the expense of converting to metric and the vast amount of legacy programs, drawings, and part design families they would need to convert. This doesn't mean the imperial system is superior, only that making radical process and culture changes is costly and painful, especially when your workforce grew up using imperial units.
As for your comment that "the fasteners that hold the Sandvic inserts in are still loosened and tightened with inch fractional allen wrenches," Sandvik hasn't used any imperial fasteners in their tooling for at least a couple decades. Likely what you're seeing is a 5/64 is the same basic size as 2mm, a 5/32 is only a thou off of 4mm, 5/16" is only 2 thou off of 8mm, etc. so some imperial allen wrenches will work in metric cap screws. Besides, with regards to Sandvik, I was talking about end mills, drill diameters, rotating tool shank sizes, indexable milling cutters, milling arbors and power chucks, collet sizes, modular tooling connections, boring bar diameters, grooving insert widths, and on and on. There are multiple times more offerings in metric than in inch dimensions these days across all cutting tool manufacturer brands' products. It's not even close in fact. And if you're going to make a point about "Sandvic," and least learn to spell "Sandvik" correctly.
I’ve been following this thread since inception and have just had it shake my head at some of the stuff I’ve seen. RIFLE DUDE says it well. I’m a journeyman tool and die maker, have been working in both systems since the mid-70’s. Metric is far superior and much more logical.
The big mistake made by US industry when switching to metric was the agenda was in trying to teach everyone how to do conversions, rather than just going hard metric. That was all so complicated, because of the absurd complication of the imperial system, that your average industrial worker ran out of brain cells trying to figure it out.
One thing that hasn’t been mentioned here is the elegant relationship between everything in metric. One cubic centimeter (one milliliter) of water weighs one gram. Thus one liter of water is one kilogram. One calorie raises one gram of water one degree centigrade. Everything else fits into this model. Think of how easy it is to solve a lot of engineering problems.
When I read that one flaw of the metric system was no provision for fractions I figured we’d never get this resolved.
So fractions are not useful and mean nothing? A pound is not a useful measurement? The inch itself is not a useful measurement that has no equal in metric? Resolved? Journeyman tool and die maker? You might as well vote democrat for all the sense your making.
You seem very confused by all this Rick. What kind of machinist are you? Are you a real machinist or just a guy who loads and unloads cnc machines? Just wondering...
And then there's this gem, displaying his vast "knowledge" of units of measure:
Originally Posted by rickt300
Originally Posted by mauserand9mm
They almost got the imperial system correct: 1 MOA = 1.047 inch.
So what's the end result? Did we all agree that the metric system was the better way to go?
Why is MOA 1.047? Who in their right mind would have done that?
Oops, that was my fault. I wasn't intending to trip anyone up - I forgot to add "at 100 yards". The comment was in jest. It was an unexpected response though.
Originally Posted by mauserand9mm
Originally Posted by mauserand9mm
Originally Posted by Raspy
Whatever you said...everyone knows you are a lying jerk.
That's a bold assertion. Point out where you think I lied.
[quote=rickt300]There are two kinds of countries in the world, those that have been to the Moon and those that use the metric system.
You reckon that NASA scientists didn't use metric measurements and calculations? LMAO.
"The 257 Roberts, some people like to call it the “.257 Bob.” I think these people should be hung in trees where crows can peck at them." - David Petzal
Fractions aren't needed in the metric system, e.g. 250g is 250g, 982g is 982g, 72cm is 72cm, 1.6m is 1.6m etc. I was schooled for the most part in the imperial system but we went metric in 1967.
I like to call my trout in pounds out of habit and a lot of us older guys still do. Besides an 8lb (three figures) rainbow sounds bigger than a (3.628 kgs 8 figures) rainbow.
[quote=cra1948]I’ve been following this thread since inception and have just had it shake my head at some of the stuff I’ve seen. RIFLE DUDE says it well. I’m a journeyman tool and die maker, have been working in both systems since the mid-70’s. Metric is far superior and much more logical.
The big mistake made by US industry when switching to metric was the agenda was in trying to teach everyone how to do conversions, rather than just going hard metric. That was all so complicated, because of the absurd complication of the imperial system, that your average industrial worker ran out of brain cells trying to figure it out.
One thing that hasn’t been mentioned here is the elegant relationship between everything in metric. One cubic centimeter (one milliliter) of water weighs one gram. Thus one liter of water is one kilogram. One calorie raises one gram of water one degree centigrade. Everything else fits into this model. Think of how easy it is to solve a lot of engineering problems.
When I read that one flaw of the metric system was no provision for fractions I figured we’d never get this resolved.
So fractions are not useful and mean nothing? A pound is not a useful measurement? The inch itself is not a useful measurement that has no equal in metric? Resolved? Journeyman tool and die maker? You might as well vote democrat for all the sense your making.
You seem very confused by all this Rick. What kind of machinist are you? Are you a real machinist or just a guy who loads and unloads cnc machines? Just wondering...
You appear to be a genuine Canadian dipschit. "journeyman tool and die maker" means generally mills which also means you do little or no programming, sit on your butt after clamping you part down to the table and wait for the machine to quit running. So when I hear Journeyman tool and die maker I think maybe he would have made sergeant someday if he tried long enough.
Rict300, Your objection of the metric system is based on the fact you grew up with the imperial system, that's what you were taught, what you used for many years, what you relate to in your everyday life, and what you think in when dealing with units of measure of everything. It's understandable that you find something contrary to a system you've used your whole life to be cumbersome. It's human nature to reject that which runs counter to our experiences, is new...change in general. All these folks who you say agree with you on the superiority of the imperial system probably have similar experiences as you, and were never placed in an environment where they had to work in metric units exclusively for sufficient time that it became second nature to them. I deal with customers across all of North America, and I assure you, your experience isn't anywhere close to universal. Everyone who I interact with who have worked in manufacturing facilities that both use imperial and metric exclusively (not switching back and forth between the two systems) end up preferring metric. They may have been old school and arrived at that point kicking and screaming, but arrive at that point they did. If you don't believe me, I'm cool with that. If you have a different opinion than me, I'm cool with that too. You're entitled to your opinions, but many of your assertions are just factually incorrect. I live and work in Texas just as you do, but working for a CNC machine tool manufacturer, I'm pretty sure I interact with a broader customer base who manufacture a broader range of products than you do. Our customers cover all industries all across North America, and we routinely help them develop their processes used on our machines. I was also a cutting tool, gage and fixture designer for many years, and I've made custom cutting tools for many of these companies.
If you're spending the vast amount of your programming time standing at the machine control, then you obviously aren't using one of the better CAM software packages (MasterCam, Esprit, GibbsCam, EdgeCam, etc) or your parts lack sufficient complexity to make programming with CAM software viable. If you're starting out your programming with 3d CAD models of your parts, importing them into CAM software, and you have a good, proven post for your machine, then it doesn't make a damn what units you're working in with respect to programming time. That you insist otherwise indicates that you're behind the times on technology. I've done lots of programming in both units of measure. Programming in metric doesn't necessarily take any more time or consume more lines of code than programming in inch, and feeds and speeds are no more difficult to calculate in mm or meters/minute vs in or ft/min or mm/rev vs in/rev. It's all a matter of what you get used to using and what you're comfortable with.
I don't know what point you're continually trying to make with regards to the inch being expressed in increments of 10. Yeah, in the machining world you often work in tenths and thousandths of an inch. So what? That's not the point.
No that is the point. 1.000 is an inch, it can be broken down by .1, .010, .001 or .0001 easily. The millimeter
The imperial system is made up of a hodgepodge of units that have random, inconsistent relations to each other. 12 inches in a foot...
What inconsistency? Is there some reason not to have the yard broken into three places on a steel tape?
3 feet in a yard
And your point? Don't you think it would be nice to be able to break the meter into three very useful Parts? Or four?
...5280 feet in a mile...
I find the mile a more useful distance than a Kilometer. Looks much better on a speed limit sign.
231 cu/in in a gallon, 8 pints to a gallon,
Kind of funny you are, 128 ounces in a gallon, 4 quarts, 8 pints, 2 1/2 gallon where is the problem?
etc. Numbers all over the place. In the metric system, EVERY unit is expressed in increments of 10 to all other measures across the whole system...10 mm to a cm, 100 cm to a meter, 1000 M to a KM, etc.
Funny again, useful distances and measures do not wholly depend of their ease of being multiplied by ten. The foot divided into inches divided into fractions is more useful than the meter divided int mm and cm in the real world. And much faster to use. That said have you ever used a metric steel tape?
A mm is just under .04, pretty small and counting the gaps between the lines means you better have good eyes! And ten Centimeters is just under 4 inches, meaning the meter is divided into 10 sets of 100 centimeters. a centimeter measures not much more than 3/8ths of an inch. I have to say that using a metric steel tape is a pain compared to using an Imperial steel tape with it's visually easy markings.
Even if one is completely entrenched in the imperial system, how anyone can't see the inherent superiority and simplicity of a system that relates all measures to each other in increments of 10 is mind-boggling.
Where is this superiority revealed? On a calculator? Even then the fewer figure needed to do calculations gives the Imperial system the edge.
Yes, Bell Helicopter, Lockheed Martin, and Boeing still use imperial units, but not across the board, and that's beginning to change as they pursue international contracts and work with international partners and the military. The US military went completely to metric units a long time ago. Bell Helicopter now uses primarily metric units in the V22 Osprey program. Following a disastrous, expensive loss of the Mars Orbiter due to a calculation error where NASA was working in metric and Lockheed was working in imperial units, Lockheed began converting over to metric in their space-related projects. They also work in metric on projects where they partner with contractors and governments overseas. And I don't even want to get started on the mind-numbing stupidity, inefficiency, and waste at some of those defense-related companies due to the difficulty in making process changes and conflicts with the unions which cause them to still use a lot of 1970's and 80's technology tooling and equipment. Many US manufacturers have stuck with the imperial system simply due to the expense of converting to metric and the vast amount of legacy programs, drawings, and part design families they would need to convert. This doesn't mean the imperial system is superior, only that making radical process and culture changes is costly and painful, especially when your workforce grew up using imperial units.
Do not forget we gain nothing in precision going to the metric system, nothing. I disagree with that there is a lot of 70's and 80's machinery out there simply because most of it has been replaced with CNC machines by 1990, though there are some engine lathes and mills in most shops used to build fixtures or rough parts. Interestingly I have made a lot of V22 parts though mostly 8-10 years ago and the inch still ruled then. So you are blaming the imperial measuring system for NASA and Lockheed not telling each other what they were doing?
As for your comment that "the fasteners that hold the Sandvic inserts in are still loosened and tightened with inch fractional allen wrenches," Sandvik hasn't used any imperial fasteners in their tooling for at least a couple decades. Likely what you're seeing is a 5/64 is the same basic size as 2mm, a 5/32 is only a thou off of 4mm, 5/16" is only 2 thou off of 8mm, etc. so some imperial allen wrenches will work in metric cap screws. Besides, with regards to Sandvik, I was talking about end mills, drill diameters, rotating tool shank sizes, indexable milling cutters, milling arbors and power chucks, collet sizes, modular tooling connections, boring bar diameters, grooving insert widths, and on and on. There are multiple times more offerings in metric than in inch dimensions these days across all cutting tool manufacturer brands' products. It's not even close in fact. And if you're going to make a point about "Sandvic," and least learn to spell "Sandvik" correctly.
There are thousands of old turning tools out there that you can use Sandvic inserts in, They are made in specific sizes and shapes.
![[Linked Image]](https://i.imgur.com/Ck5vtVI.gif)
. Nice Ending.
![[Linked Image from i.postimg.cc]](https://i.postimg.cc/yYDjsxrQ/IMG-0124.jpg)
