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New to the trade and in a metric shop: Are metric measuring tools by best bet?

cskolnick

Plastic
Joined
Feb 6, 2015
Location
Asheville
Hey all.
As stated, just got entry level position as a manual machinist and I need some of my own measuring tools.
We work primarily with metric prints. Although I can and do covert to inches, I am debating if working and measuring straight metric would be in my best interest: Less chance to introduce human error when converting between un its.
A lot of the guys covert on the prints and measure inches with the reason being, as I am told, they just happen to have all inch measuring tools that they have had since the get-go of their careers. Well, since I am new and do not have measuring tools yet...

Any thoughts?

I do suppose if I went digital on all my devices it would be a mostly non-issue. With that said, I am on the fence about the expense of digital mics, at least this early in my potential career. Additionally, my desire to have a dial display for my most often used 6"/150mm is non-negotiable: I just enjoy reading the dial.

The other consideration for me is that I may not be in this particular shop forever and most places still seem to be in inches. Would rather not have to buy all new tools again if this was to come up. It also seems like CNC programing is still heavily favored by inches. This I could be wrong about but I am taking an Intro CNC course this Fall semester at the community college, so it is something I am factoring in.

Thanks for any advice/feedback.

FWIW I am planning on these metrology tools to get me started. Units are in inches, please free to convert if desired :)


6" dial caliper
8" and 12" digital calipers
0-3" mics (digi or analog not sure yet)
2ct. metric scales
1ct. inch scale
protractor/right angle/center set with rule
2 sets of parallels
Vertical dial indicator with mag base
 
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The Mitutoyo digital mics are pretty nice. I buy them from Zoro when they have 20% or 30% off sales. Are non-digital mics that much cheaper?
 
IMO, you want two scales, one with 5R markings and one metric. I like the white on black ones. You can't go wrong with Mitutoyo digital mics and metric and inches are but a button push away. Ditto on Mitutoyo digital calipers. Wouldn't own anything else because of the reliability and long battery life. Unless you have some specific need, those protractor/angle/center sets are rarely used. The good ones are expensive and the cheap ones are, well, cheap. The common import parallels are fine, get the standard width set and the narrow spring steel set. Depending on what you do, I'd want a depth mic, digital or analog, as you like. Also, a set of various machinist squares.
 
To offer my $.02 worth of "advice", if you're starting out in a shop that mainly deals with metric, don't have any measuring tools and plan to work there for a long time, or move to another shop that deals with metric, I would by metric tools. Converting between units only adds the the chance of mistakes, and as a machinist, you are going to want to take as much chance for errors out of the equation. If you do have to make a mistake, make sure you can blame it on the engineer who designed the part lol.
Personally analog tools never need a battery change and may need the calibration done, or at least checked to the standards of the shop, but don't let the old timers tell you they're bad just because they're digital. It may be a smart choice if you have to find a job where the inch is still king and would make purchasing new measuring tools necessary.
So far in my career, I have been in shops that run inch and have invested in tools for that system. So if I did have to go to a metric shop, I would be on the hook for thousands of dollars if I had to replace everything in my box.
 
The digital Mitutoyos are indeed really nice. Inch/Metric toggle button and absolute + relative measurements. I have not once ever needed to re-zero the absolute reading since I took my calipers out of the box years ago. And the battery lasts forever, even if you forget to turn them off. I've changed my watch batteries several times since I've owned these calipers whilst the calipers are still on their original cell. They're rock solid.

Beware of counterfeits, for I have heard they are aplenty.
 
Best to check with your foreman.
Some shops don't allow digital instruments on the floor...Too easy to reset/loose the calibrated zero which mechanical measuring tools won't .(mechanical = absolute)

If you are running machines with only mechanical reading dials (lathe) if the dials are in inch units then i would buy inch measuring tools....Easier to do the conversion on the print and work
directly with the units on the machine. If eve4rything is fitted with DRO's then mo issue buy the measuring tools that you are most comfortable using/reading....

Cheers Ross
 
I have been in the trade for 46 years. I have been self employed with my own shop for the last 15 years. All of my work is metric and I still cannot work in metric directly. I have to convert everything to imperial. If I were you I would work with metric tools before you become imprinted in imperial like me. The switch to metric in the U.S. is slow but it is eventually going to happen.
 
Here we go again...
Sorry. Some of us hate metric. If the independent thinkers of the US can stand up to a potentially mortal disease, seems to me that defying metric ought to be trivial.

It's a piece of shit system. The entire selling point is, "Everything is divisible by ten !" So what ? Do you have ten arms ? Ten legs ? Ten titties ? It's a stupid justification. Different units work better for different purposes.
 
As much as I hate Metric and digital measuring equipment, I'd have to recommend the Mitutoyo digital calipers. You can switch between Inch and Metric at will.
Get a good calculator, and get ANALOG micrometers. IMO you simply cannot replicate the accuracy of analog micrometers if you go digital. I would suggest inch micrometers, but since you're new to the trade you don't really have any habits to break so you might benefit with metric micrometers and indicators.
Although, if for some reason this job doesn't work out and you find yourself at another shop that doesn't do metric you're hosed and will have to either buy inch tooling or convert from metric to inch.

Question though....you're hired as a manual machinist. Are the machines that you'll be running metric on the dials? That's another thing to consider. Say you're running an engine lathe with no DRO and have to use the dials.If they're imperial then the levels of confusion and chances of error are only compounded.
 
My opinion is mitutoyo digital calipers. If you will be running cnc machines the coolant proof ones are nice.

And mitutoyo digital micrometer set. Im fairly new but these are by far the best micrometers I’ve used. The quantamike versions are also nice but I’m a bit more skeptical to their accuracy. The regular ones are great though. They are extremely accurate and coolant proof.
 
25,50,75 blocks and metric gauge block set. and do not forget the 25 mm adjustable wrench. Comes in handy, alongside the metric protractor.
 
Sorry. Some of us hate metric. If the independent thinkers of the US can stand up to a potentially mortal disease, seems to me that defying metric ought to be trivial.

It's a piece of shit system. The entire selling point is, "Everything is divisible by ten !" So what ? Do you have ten arms ? Ten legs ? Ten titties ? It's a stupid justification. Different units work better for different purposes.

bwhaaaaaaaaaa...you lived in a freakin metric country! and in the US all measurements are in tenths and thou inches for machining. Why are you having a belly ache over dividing by ten? Are you a carpenter? There is the only place where a 1/16th even makes sense.

I grew up metric, but all my analog tools are now imperial...I guess I am considered amibimetrologous? For woodwork I hardly ever use a tape measure, I cut things to fit, for metal I use imperial, and metric for bearings, and the odd times you need to use a metric fastener.:)
 
I have been in the trade for 46 years. I have been self employed with my own shop for the last 15 years. All of my work is metric and I still cannot work in metric directly. I have to convert everything to imperial. If I were you I would work with metric tools before you become imprinted in imperial like me. The switch to metric in the U.S. is slow but it is eventually going to happen.

Jeez that takes some believing
Tony
 
I grew up imperial and switched to metric; and I'm never switching back.

I have some imperial mics, never used them.

Ok, to the original post; your standard micrometers aren't so expensive, so I think you should go with whatever the other guys in the shop are using.
Because they will be talking and working in those units.
 
If you want to keep converting for the rest of your life - than go imperial
If your shop is mostly metric they will eventual get rid of those old imperial machines - unless they still employ some Oldtimers who will die an imperial death.
 
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The metric system is loathsome. It is a scientific fact that using it automatically causes a reduction in the length of your pee-pee by, well, a bunch of centimeters. It makes any man less of a man.

That said, if I were working in a shop that used metric values....I sure wouldn't lose the time and effort needed to measure in God's Method then convert it to metric. Aside from the pain of doing that constantly, it introduces the inevitable result that you'll make a mistake in conversion at one point or another. I'd buy metric measuring tools and spend my time reading up on all those penis enlargement and Porsche ads.
 
As much as I hate Metric and digital measuring equipment, I'd have to recommend the Mitutoyo digital calipers. You can switch between Inch and Metric at will.
Get a good calculator, and get ANALOG micrometers. IMO you simply cannot replicate the accuracy of analog micrometers if you go digital. I would suggest inch micrometers, but since you're new to the trade you don't really have any habits to break so you might benefit with metric micrometers and indicators.
Although, if for some reason this job doesn't work out and you find yourself at another shop that doesn't do metric you're hosed and will have to either buy inch tooling or convert from metric to inch.

Question though....you're hired as a manual machinist. Are the machines that you'll be running metric on the dials? That's another thing to consider. Say you're running an engine lathe with no DRO and have to use the dials.If they're imperial then the levels of confusion and chances of error are only compounded.

I have to disagree about mics. The Mitutoyos will split tenths and are dead accurate. Don't know of any conventional "analog" mics that are as good. I work for a metric company and we have DROs on the machines, but after decades with imperial I still think that way. I know how big a 0.001" step is when I run my fingernail across it. No freaking idea what a 25 micrometer step feels like! An interesting thing about DROs- I can actually work faster with dials, and with almost no loss of accuracy if the machine is good.
 
I'd like to underscore the brief comment by JustASparky in post #5. Really clever counterfeits of Mitutoyo measuring instruments are out there, and it is wise to be suspicious when you come across a favorable price, especially one advertised by an outfit that is not a familiar supplier to your shopmates. I have found that when suspicions arise about a particular instrument, a call to Mitutoyo will sort things out. They will tell you the clues (e.g., a small size tenths numeral) that are red flags. And in case you are wondering if it really matters whether you use a genuine or a counterfeit Mit as long as the measurement is "accurate", my answer is yes it does.

-Marty-
 








 
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