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PPP MMM
01-05-2008, 03:59 PM
It's a pity that all rifle actions are not made in metric. Standard M26X1.5, M28X1.5, M30X1.5 would virtually accomodate for any possible scenario. The gunmakers in Europe and Japan made the conversion from once imperial to metric without any hassle. Nice and easy, simple to measure and to work with and everybody be certain what the thread actually is. The American imperial threads are far way too complicated and difficult to measure. What something like 1.187" 20TPI supose to be? If one doesn't know the actual exact size, simlpe measuring is of little value. If there is a misprint and says 1.183" 20TPI one could have an unnecessary headache to figure out the real size eventually. With a metric thread one simlpe flick with a vernier or even a ruler would be enough for one to be right on the track.

Shoot well
Peter

Dennis Sorensen
01-05-2008, 04:13 PM
Boo! - you can have your metric... pain in the ass if you don't have metric gears.

There is nothing hard about measuring an action and fitting a barrel successfully the way it is... some people try and fit too tight when a little loose is better. (V threads not square)

burtona
01-05-2008, 04:27 PM
Major PIA to cut metric threads on my equipment. All my measuring stuff is in Std. Don't want to ever cut another metric thread on my lathe and sure don't want to buy all metric measuring tools too.

gunmaker
01-05-2008, 07:17 PM
If you think about it the inch system of thread has to be more accurate than metric because of the incremental error stacking up from thread to thread. Kind of like resetting your odometer every time you stop your car and later add up all the numbers. Threading on a metric lathe is no real picnic either. Reason being it's not based around fractions. Inch threads are pretty dirt simple on a inch machine. Especially if it has a 4 pitch lead screw and the thread your cutting is a multiple of 4. Just grab the half nut whenever you want.
gunmaker

Jay, Idaho
01-05-2008, 09:32 PM
I don't think that either system is superior or inferior to the other. Each is easy to work with and equally accurate, IMO. Yes, you are a lot better off working with the same thread system that your lathe is based on but that is something that is a problem for everybody.
I'll give you one thing, though. The fact that metric threads have their pitch designated by actual pitch sure beats having to divide 1.000" by the TPI to get the pitch.
Most problems associated with using the Metric system in the US is caused by people wanting to convert everything. Just think and measure in mm and forget about inches when dealing with metrics.
We all have opinions.

Jay

sicero
01-05-2008, 09:33 PM
I have a hunting buddy who own a machine shop and he tells me a bigger percentage of their work is specified in metric every year. Kenny

gunmaker
01-05-2008, 10:20 PM
I might be a little outspoken on metrics being forced on the US population. Usually I argue with my mad scientist father about it every time I see him. There is a simplicity about the metric system that spooks me. Think about it. Your kid goes to school and in math class they say "Today we're going to learn the metric system. All you have to do is move that little decimal point one way or the other. Any questions class? NO?? Everybody gets an A today, class is out early." It replaces fractions to the degree that the brain gets lazy. The brain is like a muscle, the more you use it the better it gets. Kind of like buying your kids a calculator for a required grade school supply. If they don't have to think too hard, they won't. I'm not against the metric system in other countries. I just don't want it forced on me or my kids. I think we should get other countries to adopt the inch. How do you think they would like that?
gunmaker

Dave Short
01-05-2008, 11:24 PM
I don't think that either system is superior or inferior to the other. Each is easy to work with and equally accurate, IMO. Yes, you are a lot better off working with the same thread system that your lathe is based on but that is something that is a problem for everybody.
I'll give you one thing, though. The fact that metric threads have their pitch designated by actual pitch sure beats having to divide 1.000" by the TPI to get the pitch.
Most problems associated with using the Metric system in the US is caused by people wanting to convert everything. Just think and measure in mm and forget about inches when dealing with metrics.We all have opinions.

Jay

This is the whole thing in a nutshell. While it is true that more and more of our drawings are metric, it is nothing to get excited about. I quit converting some years ago, and just learned to deal with the metric system. Most machine controls, electronic measuring equipment, and machining software can be easily switched between the two systems. An easy way to visualize or quantify metric dimensions if you are used to the english system is to use these ratios: 1mm is very close to .040". 1.5mm is very close to 1/16".

As far as threading goes, there is little difference, except that mixing the two systems on a manual machine causes difficulties.......which if understood really are not that big of a deal. There really isn't any practical advantage to the metric thread, though....the basic lead/pitch and diameters are the only numbers that appear more straight forward....the rest of the math ends up carried out to the right of the decimal point anyway.

-Dave-:)

NesikaChad
01-06-2008, 07:39 AM
Folks there's nothing hard about going from Metric to Imperial or vice versa.

spend 30 bucks for a copy of Machinery handbook and every thread pitch imaginable is listed for you.

Including relevant pitch diameters, major and minor diameters, every dimension regarding a thread pitch is right there in B/W.

conversions are easy.

One millimeter is .03937" in length

25.4 millimeters make an inch.

Fresh batteries in calculators encouraged.

Enjoy!

Dave Short
01-06-2008, 08:47 AM
Folks there's nothing hard about going from Metric to Imperial or vice versa.

spend 30 bucks for a copy of Machinery handbook and every thread pitch imaginable is listed for you.

Including relevant pitch diameters, major and minor diameters, every dimension regarding a thread pitch is right there in B/W.

conversions are easy.

One millimeter is .03937" in length

25.4 millimeters make an inch.

Fresh batteries in calculators encouraged.

Enjoy!

Chad,

First, Thank you for your service. My family prays nightly for those who are somewhere other than in the comfort of their home, with their family, for the good of the rest of us.

This thread started out about using all metric threads instead of what we are all used to. Jay pointed it in the direction that we're better off to just learn metric, and use it when necessary. I decided some years ago that converting was counterproductive for many reasons, and just learned to use which ever system the job was drawn to. Once used to it, I wished I'd given in sooner.

I'm with you on the Machinery's Handbook.............having a machine without owning the book is kind of like painting your windshield black and scraping a little opening just in front of your eyes. Just to prevent sticker shock, though, You're a little off on the price..........it goes for nearly three times that thirty bucks.

-Dave-:)

PPP MMM
01-06-2008, 08:55 AM
At last someone here is able to understand the whole concept of this silly saga. In my original Post I wasn't complaining if it is hard or not to make and fit the thread, but to be able to measure the actual thread with something as stupid as a bricklayers ruler. It doesn't take genius to figure out that to fit a thread properly one needs to take the same care regardless of what the thread is called. You can measure metric with a ruler because it comes in total figures such as 5, 16, 20, 24, 30 x the pitch in mm. To go back to my original post and one can see that my example of Gilkes thread 1.187" 20TPI would be much harder to measure exactly and most definitely not with a ruler. If the same size was a metric it would be called M30.1498X1.27mm. If one of you know someone who would be able to measure that thread with a ruler, please let me know, as I want to be second to know him too. To say it simply the metric is epitomy of simplicity the imperial is the epitomy of complexity, however both can be made to the same exact tolerances, the size of the material is the same only the name is different, or is there someone here who is going to argue that his imperial micrometer is more accurate then mine with a metric thread? Give me a bucket.

Shoot well
Peter

Dave Short
01-06-2008, 10:07 AM
To go back to my original post and one can see that my example of Gilkes thread 1.187" 20TPI would be much harder to measure exactly and most definitely not with a ruler. If the same size was a metric it would be called M30.1498X1.27mm. If one of you know someone who would be able to measure that thread with a ruler, please let me know, as I want to be second to know him too.
Shoot well
Peter

Most folks would use a thread pitch gage for either Metric or Unified threads.............what is the big deal about measuring with a ruler, anyway?

-Dave-:):p

bglenn
01-06-2008, 10:37 AM
If you take a scale that is marked in 32nd/16th and measure 1.187" there is no problem measuring it. And by the way 1.187" used as a fraction, just as a even metric would be, is 1 3/16" or 1.1875". If you use the right tool for the job there is no probllem with either thread system(except on machines that are a lot of trouble to set up for metric).
Glenn

Dave Short
01-06-2008, 10:45 AM
And by the way 1.187" used as a fraction, just as a even metric would be, is 1 1/16" or 1.1875".
Glenn

Glenn, before someone makes a big hairy deal of it, you (accidentally, I'm sure) state that 1.187 is 1 1/16................it is actually 1 3/16.

-Dave-:)

Bnhpr
01-06-2008, 11:11 AM
The industrial world is going metric.

As an engineer for 15 years, I have seen a transition from 10% SI to 90% SI. The world is standardizing. And the standard is the metric system.

The US, if it plans on competing in the industrial future, will also go to SI units.

Gunsmiths are one of the few industries not converted to SI, because of the market. But give it some time, Americans will be buying rifles from China soon enough.

:(:(:(:(


I know I'm picking a fight here, and I see all your view points, but why is the world going to metric?

Because the metric system is better and easier to learn.

Why is it better?

Because you were born with 10 fingers.

Think this through to conclusion and you'll agree, if you do not, your not thinking.

10mm = 1 cm 100 cm=1m 1 cm2=1ml 1ml of water weighs 1gram. 1metric ton=1 cubic meter in volume. the list goes on......

crb
01-06-2008, 12:05 PM
The American imperial threads Shoot well
Peter

Peter,
It's English measure, not American ;)

gunmaker
01-06-2008, 12:23 PM
There was machinist named Peter
Who wouldn't accept the new meter
So he gladly retired
And now he's inspired
To drink beer by the pint, not the liter

Dave Short
01-06-2008, 12:57 PM
There was machinist named Peter
Who wouldn't accept the new meter
So he gladly retired
And now he's inspired
To drink beer by the pint, not the liter


That is really funny!

But.......

Please be careful where you apply the title "Machinist"....................1 out of every 1,000 who can run a machine is a Machinist.

-Dave-:)

PPP MMM
01-06-2008, 02:54 PM
BOY oh boy, you two should first decided which one is which. To me 1.187" is not 1.185" and maybe not to you two, but to everybody else there is a big difference between 1 1/16" and 1 3/16". Why not to complicate the simple metric? Let's use an imperial and we all can get confused. When you two w'll finally decide which one is the right answer please let us all to know. I only wish it was a metric...now maybe you wish too. Just please do not end up as a one of the 999

Shoot well
Peter

Jay, Idaho
01-06-2008, 05:10 PM
Peter,

I don't know why you are so hung up on fractions of an inch. They are not really used by toolmakers and machinists, fractions are used by carpenters and sheetmetal workers. Toolmakers and machinists use more sophisticated tools, whether working in inch or metric. These tools typically measure to 100-500 microns but they are not referred to as microns. The phrases are "ten thousandths of an inch" or "hundreths of a milli".
Ya gotta be comfortable in both worlds if you wish to move around in manufacturing today. A 6mm barrel is easier to order @ 30" in length, rather than 762 mm or 76.2 centimeters.
We all have opinions,

Jay

John Kielly
01-06-2008, 05:20 PM
Peter Paul Mauser got it right first time when he used the x 22 thread on his action screws - the only fine(ish) pitch common to both metric & imperial lathes.

pduryee
01-06-2008, 05:42 PM
My grandfather said that since he and his pals won the big war, we got to choose which system to use and it wasn't metric. Thanks Gramps.

PPP MMM
01-06-2008, 05:55 PM
Jay you don't seem to follow here because if you were you would notice that with the fractions I was refering to the other two dudes. I'm a metric man and if I've had ever to deal with an imperial, fractions and the Amer. Stand. it was only because of American made actions and/or total over haul of old machinery such as lathes, precision grinders and so on. Othervice I wouldn't be looking for it. It's funny that only one dude picked up that what I was calling it an imperial and it's actually an American Standard. Well done, you'r the one and we all are the rest of the 999.

Shoot well
Peter

NesikaChad
01-06-2008, 06:34 PM
I'll fight it. The metric system that is. Not cause I don't like it, but because I'll be damned if I'm tossing all my good inspection instruments to buy new ones.

NEVAR!!!!

I just spent close to 2500 a few months ago on a new set of Mics for my shop that doesn't even exist yet.

We won't even talk about gauge pins and blocks.

Or tooling.

Call me little big horn or the alamo.

The fraction is strong in this one

Sandbag
01-06-2008, 09:08 PM
Chad

None of your measuring instruments measure in fractions. They measure in somewhat of a metric system. .0001 - .001 - .01 - .1 of an inch, not 1/128th - 1/64th - 1/32nd - 1/16th -1/8th ect.

Our monetary system is for all intents and purposes, a metric system. The easiest system in the world.

Have you ever thought about the fact that many tap drill sizes do not convert to a fraction? 1/4-20 is as good an example. Quick, what is the decimal size of a #7 drill?

We'll be metric some day, particularly with most of our manufacturing offshore now. This doesn't mean you have to get new equipment, just a $20.00 TI calculator.

I've been an injection moldmaker for about 25 years now and have had to use both systems. Believe me, the metric system is much easier. It's just a a matter of using it a bit, then you'll apperciate it's simplicity.

By the way, I don't own one metric measuring tool and believe me, I have well over $10,000 in measuring equipment. Have to replace the calculator occasionally though.

John

Dennis Sorensen
01-06-2008, 11:35 PM
I'm a metric man and if I've had ever to deal with an imperial, fractions and the Amer. Stand. it was only because of American made actions and/or total over haul of old machinery such as lathes, precision grinders and so on.

The good old Mauser 98 made in Germany doesn't have a metric thread on it... :D

PPP MMM
01-07-2008, 02:07 AM
Dennis no one ever said it has a metric thread. Just make sure that you get the 55 degree angle on it at first so you don't join the 999 without a fight.

Shoot well
Peter

Dave Short
01-07-2008, 05:54 AM
*The Metric system is here to stay............it has been a part of manufacturing in the US for longer than most realize, and will likely just continue to be used on more and more of the drawings we see.

*Having two systems in place isn't anything to get all worked up over.......if either one was truly superior to the other it would have pushed it out a long time ago.

*I could care less what the thread is on an action...............If I choose to work on one, I'll thread to fit it.

*Most of this thread has been a waste of time, and is a good example of why we ought to be using real names. Of course, using our real names would only serve to keep civility if someone in the game actually knows the individual.

*How many Machinists are there in 1,000? (the rest are 'chiners).......Those who know, know. Those who don't, don't matter.

-Dave-:):)

Rustystud
01-07-2008, 06:18 AM
We would be using metric here in the US for everything if it were not for you engineers. The Britts and the US dominated the industrial world after WWII. With thie unified english speaking world in charge industrial standards had to be established. NATO ammo, Unified fine, Unified Course, Imperial and many others just look at the Machinist handbook. There are so many threads it isn't funny. In the US a group of automotive engineers got to gether and established the SAE (Society of Automotive Engineers). My 1999 Ford has about as many metric screws and bolts ast it does SAE bolts and screws. This is due to the parts that are farmed out to foreign vendors. In the
1970's the US government got a wild hair up their backside and decided we would go metric. But resistence in the market place has slowed the tranisition.
I have a stash of bolts and screws in my shop and yes, I have both Unified Standard, Unified fine, SAE, and Metric and some european metric and chi-com metric. Guns on the other hand also have 10, 12, 13, 14, 16, 18, 20, 24, 28, 32, 36, 38, 40, 42, 48, 60, 64, 68, 80, 88, 96, 120 thread per inch screws. I am sure I forgot some. Thank you engineers for keeping our mechanical world simple.

I agree metric makes sense, but who said governments that are political will ever do what makes sense.

Rustystud

JerrySharrett
01-07-2008, 07:57 AM
We would be using metric here in the US for everything if it were not for you engineers.

Rustystud
I disagree! In the 70's we, at Kodak, spent several million dollars to change drawing dimensions from inch to metric. This was before we had CAD systems so the drawings had to be changed by redrawing them. We spent tens of thousands of dollars buying metric measuring tools. We now had 12 inch metric scales, we now had 25.4 mm diameter bar stock that was still one inch in diameter.

The reason the US to metric fell through, and this is the truth, was spelling. The ISO, International Standards Organization, wanted to spell meter, meter. They wanted to spell liter, liter. The SI, Standards International', based in France wanted to spell meter, MITRE'. They wanted to spell liter, LITER'.

SI thought they had the right to establish spelling because they had the master atomic clock. They even printed bumper stickers saying "Because MITRE and LITRE are neater".

The US became (was) the most industrialized nation in the world using the inch system. Why should we change?? The ChiComs are making our inch stuff just fine.

Bnhpr
01-07-2008, 08:15 AM
We would be using metric here in the US for everything if it were not for you engineers. The Britts and the US dominated the industrial world after WWII. With thie unified english speaking world in charge industrial standards had to be established. NATO ammo, Unified fine, Unified Course, Imperial and many others just look at the Machinist handbook. There are so many threads it isn't funny. In the US a group of automotive engineers got to gether and established the SAE (Society of Automotive Engineers). My 1999 Ford has about as many metric screws and bolts ast it does SAE bolts and screws. This is due to the parts that are farmed out to foreign vendors. In the
1970's the US government got a wild hair up their backside and decided we would go metric. But resistence in the market place has slowed the tranisition.
I have a stash of bolts and screws in my shop and yes, I have both Unified Standard, Unified fine, SAE, and Metric and some european metric and chi-com metric. Guns on the other hand also have 10, 12, 13, 14, 16, 18, 20, 24, 28, 32, 36, 38, 40, 42, 48, 60, 64, 68, 80, 88, 96, 120 thread per inch screws. I am sure I forgot some. Thank you engineers for keeping our mechanical world simple.

I agree metric makes sense, but who said governments that are political will ever do what makes sense.


Rustystud


Rusty,

I do not have the time to compose a lengthy dissertation on post WW2 economics, but I have worked internationally/domestically in the oil and gas business for the past 13 years.

I've lived in Singapore for 3 1/2 years, Belfast NI for a year, and am now working back in the US. I have been involved with manufacturing Diesel engines in Augsburg Germany, at the MAN B&W plant that holds Rudolf Diesels original patent. The CAT engine plants in Peoria and Lafayette Illinois, Drilling equipment in Houston, Tx, Kristiansand Norway and various other locations worldwide. Shipbuilding operations in Singapore, Ulsan, South Korea, Brownsville, TX, Galveston, Pascagoula, Harland and Wolfe, In Belfast, where they built the titanic. You name any industrial country in the world, that builds machinery, and I've probably done business with them.

You can blame me, but here is what I am certain of.

U.S. manufacturing, education systems and everyday life WILL convert to SI units, or the U.S. will be economically and technically OVERRUN by the rest of the world, and the U.S. will become a poor ass country that cannot defend itself, like Communism fell, so will U.S. capitalism, because it cannot adapt to change.

Do you realize what is happening to the US dollar, and why?

Wouldn't it be nice to see Made in USA attached to something that is made better than elsewhere?

gunmaker
01-07-2008, 10:03 AM
like Communism fell, so will U.S. capitalism, because it cannot adapt to change.

Do you really believe this?

Man I feel stupid. I thought capitalism was an economic system where business and manufacturing are privately owned and operated with the intent of making a profit. Where the pricing of goods and services are based on supply, demand and competition in an open market.

Sounds like capitalism constantly adapts to change. Until the government gets in the way. This only happens on a daily basis.

capitalist gunmaker

Bnhpr
01-07-2008, 02:06 PM
Do you really believe this?

Man I feel stupid. I thought capitalism was an economic system where business and manufacturing are privately owned and operated with the intent of making a profit. Where the pricing of goods and services are based on supply, demand and competition in an open market.

Sounds like capitalism constantly adapts to change. Until the government gets in the way. This only happens on a daily basis.

capitalist gunmaker

I see your point blaming the government, but who is the government? You? Me?

My point is that Americans need to learn and embrace metrics. Ceo's, engineers, machinists and the guy sweeping the shop.

PPP MMM
01-07-2008, 06:23 PM
Dave you'r really "Short" because you still can't get it and even contradicting your self in what you say. At one breath you say that everything w'll be metric one day and in the next breath you state about the no superiority of one over the other. There is no any MECHANICAL advantage, as the only SUPERIORYTY lies in the SIMPLICITY of the METRIC so even someone who is dull can use it without geting confused. The Yanks and the Poms so far only survived the change because not just of their patriotic stubborness to any change, but also because of economical strength and greed. The change is very costly. One day it will happen and the longer it takes the more it will cost. Did you finally got it???? By the look of it, You'r one of those who would benefit the most.

Shoot well
Peter

Butch Lambert
01-07-2008, 06:54 PM
Dave, I guess you and I are sh-t out of luck.
Butch

Dave Short
01-07-2008, 06:57 PM
Dave you'r really "Short" because you still can't get it and even contradicting your self in what you say. At one breath you say that everything w'll be metric one day and in the next breath you state about the no superiority of one over the other. There is no any MECHANICAL advantage, as the only SUPERIORYTY lies in the SIMPLICITY of the METRIC so even someone who is dull can use it without geting confused. The Yanks and the Poms so far only survived the change because not just of their patriotic stubborness to any change, but also because of economical strength and greed. The change is very costly. One day it will happen and the longer it takes the more it will cost. Did you finally got it???? By the look of it, You'r one of those who would benefit the most.

Shoot well
Peter

Again, you make my point about rude people who hide behind their "handle". You may make all the insults you want, but be aware that you are showing your true mentality and small-mindedness.

There is no contradiction in the statement that we'll be all metric one day and that one system is not superior to the other; in fact, I don't see where one statement has anything to do with the other.

It is interesting that your final insult is that, as you see it, I'd benefit the most from the simplicity of the metric system........of all the responses, you are the one who is most excited about the simplicity of it.

BTW, you get the gold star for your forehead; I don't recall anyone making insults of anyone's sirname since grade school.

-Dave-:D

Dave Short
01-07-2008, 07:09 PM
Dave, I guess you and I are sh-t out of luck.
Butch

Butch,

How refreshing it is to address someone with a real name! Funny thing about these threads, some folks don't realize how much their character (or lack thereof) sticks out.

Another funny thing, I'd mentioned in an earlier post that I've been using the two systems, usually on a daily basis, for years. There is still a mentality that we have to use one or the other, and cannot see them as independent, stand-alone systems that we can work with on an as-needed basis. I'll state again that I quit converting years ago. Darned near all of our equipment, from computer software to machine controls to inspection equipment is capable of working in either system.........we can just work within what ever system the drawing is dimensioned in.

I think we should begin to discuss the pros and cons of third angle projection vs. first angle projection.................ya think the Pee Pee Pee-mmmmmmmmm guy knows everything about those two systems too?

-Dave-:)

Dave Short
01-07-2008, 07:15 PM
Dave, I guess you and I are sh-t out of luck.
Butch

Come to think of it, I'd rather be !@#$ out of luck along side of a decent guy with a real name than walkin' in tall cotton with some mystery jerk that doesn't know his a$$ from a hole in the ground.

-Dave-:)

Butch Lambert
01-07-2008, 07:19 PM
Dave, beside having a small machine shop, I have been in the automotive business for 40yrs. I started using metric and quickly went to a combo. If you work on all of them you do both. I don't see any magic in metric and I use it on a daily basis. I believe like Gunmaker, going metric ain't the answer to our problems and also has nothing to do with us being a world power or not. It is much deeper than that.
Butch

Dave Short
01-07-2008, 07:38 PM
Dave, beside having a small machine shop, I have been in the automotive business for 40yrs. I started using metric and quickly went to a combo. If you work on all of them you do both. I don't see any magic in metric and I use it on a daily basis. I believe like Gunmaker, going metric ain't the answer to our problems and also has nothing to do with us being a world power or not. It is much deeper than that.
Butch

Butch, I don't think the metric system even makes the list of reasons why we're losing manufacturing to overseas suppliers........But I'll bet the contents of my wallet that the disparity of production costs....lead by wages, environmental, safety, and tax issues tops the list.

And with that, my work here (this thread) is done.:p

-Dave-:)

Jay, Idaho
01-07-2008, 08:11 PM
We are using both systems in the US. Look around, liters of soda, fasteners on vehicles, specs on many items, all metric (or both). The kitchen (recipes) is still not converting and 100 yards is the length of a football field. Kids are getting comfortable with both systems allowing a gradual adoption of metrics.
One thing that I dislike is C. for temperature. The F. system gives us a better feel for temperature. Ten degrees in C. is a much wider range than ten degrees F. C. is just too course, I think.
Hey, 80 cents a liter for gas might feel better than $3 a gallon!

Mountain Mike
01-07-2008, 08:30 PM
Dave SHort is absolutely correct. Work in whatever sytem the drawings are in. This is the only rational way for engineers and machinists and other manufacturing operations. Don't convert; it leads to nothing but problems.

Bnhpr is also correct. Metric is inevitable, and if the US does not adopt it, we are doomed as a manufacturing country (of course, we don't manufacture much anymore anyway; mostly we are "service" oriented (think bulls-cows)). Do you all realize that the only countires in the world that still officially use Imperial measures are the U.S.A., Tonga, and one other small country?

You should also note that the metric world is not united either. SI is used in Europe, but in east Asia Japan, Korea, and probably China use striaght metrics. The only difference is that SI measures force in Newtons while striaght metric measures force in kilograms-force (kgf). By the way, in some countries in East Asia (Japan I know for a fact) is is illegal to own measuring devices calibrated in feet and inches.

The US Government defines two types of metric conversion: hard and soft. I don't recall which is which, but for purposes of this discussion , let's say hard conversion is changing to dimensions that are rational in the metric system, and soft conversion is to exactly convert current US standard sizes to metric.

Jerry Sharrett is wrong, the US is not resisting metric because of the spelling, it because of the massive cost of retooling to switch from Imperial to hard metric. I will give you one example: in wood construction, the US standard is studs an joinsts at 12", 16", 24", and sometimes 48". Plywood, oriented strand board, gyp board, etc. comes in 4'x8' or 4'x12' sheets. Acoustical ceilings are in 2'x2' or 2'x4' modules, and light fixtures are manufactured for these modules. Any carpenter, and most other people, can lay out framing and ceilings in these modlues without much thought. These modules do not convert to soft metric worth a damn: 12"=304.8mm, 16"=406.4mm, 24"=609.6mm, and 48"=1219.2mm. Panel sizes by soft conversion would be 1219.2x2438.4mm or 1219.2x3657.6mm. It would be silly to use these dimensions in the metric system. Hard metric modules would be 300, 400, 600, and 1200mm stud/joist spacing with 1200x2400 or 1200x3600 panels. Ceilings and lights would be based on 600x600 or 600x1200 modules. This extends to stud and joist sizing where nominal size of a 2x4 would be 50x100 in hard metric. Imagine the cost if all of the US manufacturers had to throw out their current tooling and buy new for hard metric conversions. THAT is why the US has not converted to the metric system.

Mike Phillips

4Mesh
01-07-2008, 08:34 PM
I bought my first car in 1983. Shortly before, I bought wrenches, both metric and SAE. I never gave a thought as to which was which. When I came across a 10mm nut, I used a 10mm wrench. It didn't seem so hard at that time.

Now, I make all sorts of parts and regularly deal with both systems.

Go build a computer some time. You will notice that when you put the hard disk in, you use a 4-40 screw, but when you screw in the CD Rom Drive, you are doing it with an M3x.5

As far back as I can remember, these two threads have co-existed in computer cases. Go buy a brand new Western Digital Raptor Hard Disk and it will have a 4-40 screw holding it in place. Get a brand new Blu-Ray DVD Drive and that will be held in with a M3x.5. Is there an advantage? Sure. You'd be well served to use the correct screw for the job at hand.

For those of you who think the SAE system is not on the way out, just go try to buy a bearing sometime and get on with the ID or OD in SAE. Good Luck. Bearings are metric now and that's pretty much the end of that story. You will pay a premium for a bearing with a 1" Inside Diameter. Get the metric one and it'll cost less. Simple laws of supply and demand. Theres just more demand for Metric.

Our US system has lived on because our production as a nation has been very high in the past. Since that is changing, we are more and more forced to move on to the more accepted system. Numerically, we are a minority in the world so it would make sence that we should accept the standards placed before us by the world majority.

Ask anyone at the shooting range how much powder I use in my ammo and they will say, "I don't know". Not because I didn't tell them, but because I weigh my powder in grams, not grains. Why do I do this? Well, because all electronic components are made with the metric system in mind and scales of today are all made to be more accurate in grams. (because they use Grams as their native measure) They all do a math conversion to measure in grains so there is rounding error when measuring in grains. Hmmpf, immagine that. Damn near every person I know who's been told of this ignores the message. I've said countless times that scales measure in grams, and that there are 3 graduations metric for every 2 SAE, yet, they continue to use grains instead. Well, that means that their measuring error is 50% greater than mine... Duh... Do the math, accept that you will now shoot 4.100 Grams of powder, not 63.25Grains. Does 4.1 shoot more accurate than 63.25? Hell no, it's the same amount of powder. But the scale weighs it closer.

While electronics are different than manufacturing/metalworking, it's all the same. As for buying new tools, I have conversion charts so I can use the ones I have. A part made to 1.000" or to 25.400mm all measures the same to me.
Ain't the metric system great!

Bnhpr
01-07-2008, 08:44 PM
We are using both systems in the US. Look around, liters of soda, fasteners on vehicles, specs on many items, all metric (or both). The kitchen (recipes) is still not converting and 100 yards is the length of a football field. Kids are getting comfortable with both systems allowing a gradual adoption of metrics.
One thing that I dislike is C. for temperature. The F. system gives us a better feel for temperature. Ten degrees in C. is a much wider range than ten degrees F. C. is just too course, I think.
Hey, 80 cents a liter for gas might feel better than $3 a gallon!

Well, the good news is that they are the same at -40.
You think taxes are bad now, wait till Hillary has her way with us. :mad:
Orthographic projection is not a good subject to discuss here.

Feel the love

gunmaker
01-07-2008, 09:00 PM
I still haven't heard a valid argument why the USA should convert to the metric system. As others on this thread have pointed out it's not a big deal to manufacture things to metric specs here in the land of plenty. We can make money doing it, especially if we're sending it to Europe. So what's the point of converting? To become part of the big global happy family? Why? The USA is a pretty new country and just think, we got to the top of the food chain in short order using which standard of measurement?? We didn't get to the top by doing what everybody else was doing. Did we? Are we going to stay on top by copying the standards of measurement and economic policies used by third world countries? I doubt it. If we keep going along with the trends, we're all going to be speaking Spanish, sleeping with our own gender, and worshiping Allah in a few short years.

gunmaker

PPP MMM
01-07-2008, 09:32 PM
Dave every half decent machinist can work on both systems, even an imbecil can learn, but you can't still get it. You are a sad case. I rest my case

Shoot well
Peter

Big Al
01-07-2008, 09:35 PM
"We are the World" and "Cumbia". Can you say,"one world government"?

Why has the U.S. dollar been in decline? Can You say "Amero" It's not just a political move, the powers that are really in charge (read, Money folks) that seek a world of fascism, want it this way. The total enslavement of Man kind is the agenda.

Why else would the one time strongest country in the world loose nearly all it's manufacturing and allow illegal workers into the country?

Why has it been necessary to take firearms away from people the world over, why do they continue to try in America?

Why do you get the same old crap from the politicians decade after decade.

Remember it was the tax law changes in the 1950's that started the climb of corporate America and brought about the end of the family owned business.

When you have the answers to the above questions, it not hard to understand, why.

Think about the origins of "Political Correctness" and why it's such a powerful tool in the hands of the elite and their lackeys.

Freedom of speech, has been effectively drowned. :mad:

Bnhpr
01-07-2008, 10:10 PM
I still haven't heard a valid argument why the USA should convert to the metric system. As others on this thread have pointed out it's not a big deal to manufacture things to metric specs here in the land of plenty. We can make money doing it, especially if we're sending it to Europe. So what's the point of converting? To become part of the big global happy family? Why? The USA is a pretty new country and just think, we got to the top of the food chain in short order using which standard of measurement?? We didn't get to the top by doing what everybody else was doing. Did we? Are we going to stay on top by copying the standards of measurement and economic policies used by third world countries? I doubt it. If we keep going along with the trends, we're all going to be speaking Spanish, sleeping with our own gender, and worshiping Allah in a few short years.

gunmaker


In summary, my argument for conversion is simply based on efficiency. I commonly work with both systems, and find that we can be more efficient in S.I. metrics. Efficiency, breeds reliability, time savings, which, in the end, affect cost.

In the global marketplace we are loosing this race to smarter, harder working and more efficient people.

And when we lose our financial leverage on oil and technology.....it's gonna get ugly.

jackie schmidt
01-07-2008, 10:32 PM
As the owner of a Industial Machine Shop, (Marine Repair), and a Machinist for my entire adult life, I can say that we are comfortable working within both systems. But, the vast majority of our work is with the 'inch" system. Even when we recieve prints and drawings that are in Metric, we do the conversions that allow us to use our standard inch measuring tools.
Where we do run into trouble is with threads. On occasion, we will encounter a large shaft with a metric thread on the prop end. Since none of our larger lathes will cut metric, we will have to farm out the work if we have to make a new nut, or something to the such. We have, at times, just turned the thread down to the nearest American Standard and put a corresponding American Standard Thread on it.
We did this a while back. A large propellor shaft that had originolly been machined in Japan had a galled thread on the prop end. The thread was in the neiborhood of 8 inches diameter. We just cut it down to 7 3/4 4 tpi, and made a new nut. As we say in our game, nobody but the fish and crabs know that the thread is not metric anymore.
There seems to me a lot of 'venom' flowing about this subject. Heck, you would almost think we were talking about something important, like 40x's or Savages.
That being said, some of the posters in this thread need to learn that rude behavior and discourse is just that, whether you are right in your beliefs, or not. It is just as easy to get your point accross without being crass and impolite.......jackie

Dusty Stevens
01-07-2008, 10:47 PM
you never know who's looking when you want to convert to SI. here's one that wants to convert now:eek:

http://i185.photobucket.com/albums/x305/alli_ss/americanflag.jpg

dipper
01-07-2008, 11:17 PM
Bnhpr,

I just have to disagree with your statement that---
"In the global marketplace we are loosing this race to smarter, harder working and more efficient people."
It has been my experience that this is just not so.

I have spent weeks with engineers and toolmakers from China and Portugal and have friends that have worked in Japan for the last four years.
They came home for Christmas and we got to spend a day together.

From what I have seen and what I have been told, the American worker can compete with ANYONE from ANY country on ANY level.
We(American workers) can't however in most cases have much of an impact on the management in place in our companies.
I think THIS is were we are lacking ( I know it is) and many times like everything else, the little guy takes the hit.

I am old enough to remember the CEO of GM for instance saying"big cars are big money,small cars are small money" and "Americans don't want small cars."
What do you think of that statement now??
Point is the worker bees don't call the shots and when bad decisions are made well, just blame Joe lunchbox.
Consider what has happened in recent times when a CEO has been givin the boot---they still get their huge salary,their bonus, their pension, and their golden parachute.
Joe lunchbox just gets fired.

The product of any company is greatly affected by what management wants--what the powers that be want to produce.
If they want to produce a high quality product, rest assured that any worker that can't produce the desired results will be looking for another job.
It's a fact that maximum profit and bad calls have affected American companies much more then Joe Lunchbox.

Consider that the average American CEO makes ten (10) times what his counterpart makes in other developed countries.
Also, I have heard some very interesting comments (while on the job) by management people from other countries.
One of my favorites---" We love building cars in America---great workers,fairly low wages and third world benefits".
Management sets the tone and the parameters in any company.
Like another CEO from GM liked to say,"we are in the business of making money, not cars."

When Japan got a foothold in this country, they were building state of the art manufacturing facilities to build their cars.
GM was producing 1980 something cars on 1957 assembly lines.
Joe Lunchbox had nothing to do with it.

Rich

John Kielly
01-08-2008, 12:08 AM
I have noticed that despite the cogent arguments to maintain inch measurements, a number of thoughtless forum members are still quoting their rifle calibres in metrics.

PPP MMM
01-08-2008, 02:18 AM
I appreciate the lot of you for your individual input and voicing your personal opinions. It doesn't take a genius to figure out that we all had some personal views on the issue. I didn't ask anywhere or anybody how big or how small, how accurate or how loose some genius is able to fit the thread or how your two nuts or half nuts bang and rub together and if or how you'll cut them off when you will not need them anymore. I'm quiet sure that probably all of you cut both (threads) at one time or other. The KEY WORD of the subject was SIMPLICITY of the METRIC as it comes and reads in even (rounded) straight forward numbers. There was nothing more or nothing less. If we all happen to differ so be it.

Shoot well
Peter

NesikaChad
01-08-2008, 07:34 AM
Cnc.

Bnhpr
01-08-2008, 10:06 AM
As the owner of a Industial Machine Shop, (Marine Repair), and a Machinist for my entire adult life, I can say that we are comfortable working within both systems. But, the vast majority of our work is with the 'inch" system. Even when we recieve prints and drawings that are in Metric, we do the conversions that allow us to use our standard inch measuring tools.
Where we do run into trouble is with threads. On occasion, we will encounter a large shaft with a metric thread on the prop end. Since none of our larger lathes will cut metric, we will have to farm out the work if we have to make a new nut, or something to the such. We have, at times, just turned the thread down to the nearest American Standard and put a corresponding American Standard Thread on it.
We did this a while back. A large propellor shaft that had originolly been machined in Japan had a galled thread on the prop end. The thread was in the neiborhood of 8 inches diameter. We just cut it down to 7 3/4 4 tpi, and made a new nut. As we say in our game, nobody but the fish and crabs know that the thread is not metric anymore.
There seems to me a lot of 'venom' flowing about this subject. Heck, you would almost think we were talking about something important, like 40x's or Savages.
That being said, some of the posters in this thread need to learn that rude behavior and discourse is just that, whether you are right in your beliefs, or not. It is just as easy to get your point accross without being crass and impolite.......jackie


Jackie,

How do you get those intermediate sized props off? Do you hook up a high pressure hydraulic pump into a port into the taper, and break it off with it?

I know it's off the thread topic, but I had an idea for a barrel/action interface, where the barrel was fit to the action with a taper or taper/thread arrangement. This would create a very stable connection between the barrel and action, without having to tighten the heck out of it.

Have you ever heard of anything like this?

Ben

Dennis Sorensen
01-08-2008, 11:38 AM
I know it's off the thread topic, but I had an idea for a barrel/action interface, where the barrel was fit to the action with a taper or taper/thread arrangement. This would create a very stable connection between the barrel and action, without having to tighten the heck out of it.

Have you ever heard of anything like this?

Ben


... tightening the heck out of a normally threaded and shouldered barrel is absolutely no problem...


Tapered threads would be a headache to do... and shortening the chamber and adjusting headspace would be a real pain as well... and I suspect it would not shoot as well as a tightly shouldered barrel...the headache to do would be the biggest problem I think...

Bnhpr
01-08-2008, 01:36 PM
... tightening the heck out of a normally threaded and shouldered barrel is absolutely no problem...


Tapered threads would be a headache to do... and shortening the chamber and adjusting headspace would be a real pain as well... and I suspect it would not shoot as well as a tightly shouldered barrel...the headache to do would be the biggest problem I think...

Sorry for the confusion, the threads would not be tapered. The taper and threads, two separate entities.

The connection would look the same as a traditional action/barrel, only instead of a square shoulder, you'd have a 5-10mm long high angle taper, that's all, just a stupid idea.

Bill Leeper
01-08-2008, 04:52 PM
It has been done but with a 30 degree angle for the barrel shoulder. It works just fine but requires some fixtures for measurment. It is more rigid but, when it's possible to build 1/8 moa rifles with a square shoulder, it's hard to justify the extra effort.
In support of the greater rigidity claim, we used to make some largish hydraulic dump cylinders at a shop where I worked. As I recall, they had a 6 foot stroke with an 8 inch bore. The cylinder rod was five inches in diameter with a 2 1/2 inch tenon. Because the piston was relatively short (about four inches) it was able to rock a bit and we had trouble with the rods breaking off at the shoulder of the tenon. I started fitting the pistons with a 45 degree shouldr and seat and the breakage problem was a thing of the past.
By the way, fractional (binary?) sizes are used frequently in machine work. Centerless ground shafting comes in 1/16 inch sizes. O rings are sized in 32nds. So 3 and 7/16 shafting is a standard size.
How likely do you all think it is that the 303 British was conceived as a 5/16 bore (.3125) or the .375 as a 3/8? It just seems likely the British would have tried for that Imperial size!
Metric is fine but I still can't visualize sizes in metric until I convert them to inches. Regards, Bill

Big Al
01-08-2008, 05:16 PM
There is one vary welcome thing about metric. Bunches of in between sizes in drill bits. Sure can save your bacon in a pinch.

jackie schmidt
01-08-2008, 05:58 PM
There are designs that do feature a hydraulic installation, and removal. They are keyless. The only draw back is if, for some reason, the fit will not hold the pressure, and you can't pump it up.
The vast majority of large props are on a tapered fit, either 1-12 or 1-16, with a key. It is held secure on the taper by means of a large nut.
For instance, a typical 8 inch diameter shaft will have a taper fit that is 18 inches long, 1-12 taper, or "one inch taper to the foot", with a 2 inch wide keyseat. The thread that is used to secure the prop will be in the vacinity of 5 inch diameter, 4 tpi, 6 inches long. Shafts under 6 inch diameter will have a taper that is 1-16, or "3/4 inch taper to the foot".
Installation for most is hammering the nut up as tight as possible, (20 pound sledge hammer on a big slugging wrench), and then heating the prop hub up to about 300 degrees, and re-hammering the nut. After it cools, the slug the nut again, and lock it with a welded strap.
To get them off, they heat them, and use a big 100 ton jack with a "strong back", and pull bolts in the hub to apply the tonnage. Or, at least that is the correct way. If the pull bolt holes are all messed up, or the jack is in the shop, or the crew just doesn't feel like dragging it all out, (this IS a shipyard), they just heat the prop up, and "beat it till it bleeds". Crude, but affective.........jackie

Bnhpr
01-08-2008, 07:23 PM
There are designs that do feature a hydraulic installation, and removal. They are keyless. The only draw back is if, for some reason, the fit will not hold the pressure, and you can't pump it up.
The vast majority of large props are on a tapered fit, either 1-12 or 1-16, with a key. It is held secure on the taper by means of a large nut.
For instance, a typical 8 inch diameter shaft will have a taper fit that is 18 inches long, 1-12 taper, or "one inch taper to the foot", with a 2 inch wide keyseat. The thread that is used to secure the prop will be in the vacinity of 5 inch diameter, 4 tpi, 6 inches long. Shafts under 6 inch diameter will have a taper that is 1-16, or "3/4 inch taper to the foot".
Installation for most is hammering the nut up as tight as possible, (20 pound sledge hammer on a big slugging wrench), and then heating the prop hub up to about 300 degrees, and re-hammering the nut. After it cools, the slug the nut again, and lock it with a welded strap.
To get them off, they heat them, and use a big 100 ton jack with a "strong back", and pull bolts in the hub to apply the tonnage. Or, at least that is the correct way. If the pull bolt holes are all messed up, or the jack is in the shop, or the crew just doesn't feel like dragging it all out, (this IS a shipyard), they just heat the prop up, and "beat it till it bleeds". Crude, but affective.........jackie

The Rolls Royce thruster props I've removed have a hydraulic removal system that's quite effective. They have double o-rings with a test port between them you test as part of the installation procedure, before torquing the keeper hub. Apparently, on large ships, when the hydraulics fail they use explosives (det cord) to remove them. :eek: I've never seen this, but it is supposed to work well.

jackie schmidt
01-08-2008, 09:25 PM
It just so happens that Baumann Prop Shop brought two Rolls Royce Thruster props by our shop about a month ago, along with a main shaft out of the thruster. They were about 8 ft in diameter. It seems they had to do a lot of pitch work on the blades, and the subsequent moving of all that metal warped the bores to where they did not fit the tapers with a sufficient blue fit. They wanted us to re-fit them.
We re-fit the wheels, and the Rolls Rep tested the hydraulic installation and removal in our shop. They lost almost 3/16 of draw, but still were within the limits of position on the shaft.
This is pretty expensive stuff. The only vessels that use them in our area are the Harbor Tugs. Their infinite manuverability allows them to handle ships with greater efficiency. Of course, the big draw back is they do not tolerate much abuse, like getting big two inch steel cables wound up in the Kort nozzle and wheel, or backing into the bank. Lots of expensive parts can become scrap in a second..........jackie

Bnhpr
01-09-2008, 08:01 AM
It just so happens that Baumann Prop Shop brought two Rolls Royce Thruster props by our shop about a month ago, along with a main shaft out of the thruster. They were about 8 ft in diameter. It seems they had to do a lot of pitch work on the blades, and the subsequent moving of all that metal warped the bores to where they did not fit the tapers with a sufficient blue fit. They wanted us to re-fit them.
We re-fit the wheels, and the Rolls Rep tested the hydraulic installation and removal in our shop. They lost almost 3/16 of draw, but still were within the limits of position on the shaft.
This is pretty expensive stuff. The only vessels that use them in our area are the Harbor Tugs. Their infinite manuverability allows them to handle ships with greater efficiency. Of course, the big draw back is they do not tolerate much abuse, like getting big two inch steel cables wound up in the Kort nozzle and wheel, or backing into the bank. Lots of expensive parts can become scrap in a second..........jackie

And the good news is, the way the oilfield is going right now, the guy behind the wheel probably couldn't get a job at McDonalds. :(

blunt shooter
01-10-2008, 12:39 AM
Wow ! This metric thread thing really blew up.
Here in Australia we converted to metric over thirty years ago and we still have those stupid tape measures and verniers with metric on one side and imperial on the other. We also have an older generation to whom metric is incomprehensible, and a younger who only ever learned and understand metric. I, thankfully was at school in the change over time and learned in both. Fact is everything old stayed imperial, and most new things went metric. So you must learn to work in both,as neither ever goes away,and being versatile is always usefull to everyone no matter how old or young.
Common here for people to ask for such things as a piece of 1 inch pipe 2 meter's long. Or a kilogram of 3 inch nails. We have cup head bolts with a whitworth thread, sold as 4 - 4 1/2 - 5 inch ect long and the spanner to fit the nuts is 1/2 inch diam bolt- 18 mm 3/8 - 15 mm 5/16 - 13 mm .
Work that out.

Dusty Stevens
01-10-2008, 02:23 AM
I was of that generation that learned both as well here in the US in the 70's/80's. it has helped me alot. I really don't care either way except for the simple fact I don't want to be like the rest of the world. next thing you know we'll be paying with euros.:eek:

John Kielly
01-10-2008, 03:47 AM
I really don't care either way except for the simple fact I don't want to be like the rest of the world. next thing you know we'll be paying with euros.:eek:
Heck, with all the stuff your companies are sourcing from China, it will probably be Yuans. :p

Dusty Stevens
01-10-2008, 05:42 AM
that is true. sad but true:(
we just got a shipment of shackles in and had to cut every one of em up because they said china on em and there was a safety bulletin on some breaking

JerrySharrett
01-10-2008, 05:46 AM
Wow ! This metric thread thing really blew up.
Here in Australia we converted to metric over thirty years ago and we still have those stupid tape measures and verniers with metric on one side and imperial on the other. .
Work that out.
You folks in Australia gave up your guns too, apparently without a fight. That worries me about America. I'm afraid most people here would just give their guns up too as long as they got to watch American Idol, Despriate Housewives or some stupid reality TV show.

blunt shooter
01-10-2008, 03:46 PM
You folks in Australia gave up your guns too, apparently without a fight. That worries me about America. I'm afraid most people here would just give their guns up too as long as they got to watch American Idol, Despriate Housewives or some stupid reality TV show.

Right, we didn't fight too well
Living in the lucky country we are generally known as an apathetic mob.
Not seeing a threat we were under organised, not unified and small. We got sucker punched, started to fight late and wounded. The wedge was in and getting hammered. Take a lesson.

I see a lot of political comment on these forums, Obama this, Hillary that,distractions. Fellow shooters keep your eyes on the thin edge of the wedge. If it goes in hammering works,if not, all the hammering does you the honest shooter no harm.:o