[J S Machine]

I've been in the trade for a number of years and one of the first skills I learned was how to use a micrometer. Everybody knows you have to know how to use measuring equipment in this trade.

I work around other machinists / tool and die makers. One of the things that drives me nuts is their use of a mic. Now I may be wrong, but I just don't understand why people do the following:

1. Place mic over / around part.
2. Twist the thimble down until measuring faces make contact with the part.
3. lock the mic.
4. Drag it off.........

Why do people do this?????

I cringe every time I see the guys I work around do this. I've always done the following:

1. Place mic over / around part.
2. Twist thimble down until measuring faces make contact with the part.
3. READ the mic
4. Untwist the thumble and gently remove it.

I just don't get why peole drag the mic off of the part! To me, this just wears the faces that much faster. There is a possibility of chipping the faces if they are carbide. Also, if the part is out of square, and just happens to get larger in the direction you are pulling, this torques the mic...

Probably something dumb to get upset over, but I just can't stand to see people abuse their mics in this manner. It seems that way to me anyway..lol

[txcncman]

Yeah. It is probably just you. You certainly described the IDEAL way to use a micrometer. But in many situations, a micrometer needs to be used while the part is mounted in a position that it would be impossible to read it accurately or even read it at all. When I figure out a way to eliminate those scenarios, I will side with you on the idea to NEVER drag a mic off of the part being measured to place the mic in position to be readable. By the way, all of my mics have carbide faces on them.

[gordo.hogan]

I understand where you are coming from, But it is more of a way of making sure you have placed the mic in the centre of the workpiece.

Take a round component, If you place the mic too far over, then it wont be able to slide back, so by sliding it, you are ensuring that you have placed the mic correctly. Even on a square component, you slide it and wiggle it left and right to make sure you have positioned it correctly, it shouldnt go loose before it gets to the end of the component.

[michaelthomas]

I (we) drag them off all the time. We would have to be contortionists, otherwise....or remove a part from the grinder. We do it when measuring carbide, too.....which is half the time. Haven't seen any wearing of the faces or chipping, yet.

[underthetire]

Thats why they have carbide faces, and i have never seen one chipped from this.
I use mine to hold material together while i weld.

[J S Machine]

Thats why they have carbide faces, and i have never seen one chipped from this.
I use mine to hold material together while i weld.

Nice lol

[gordo.hogan]

Thats why they have carbide faces, and i have never seen one chipped from this.
I use mine to hold material together while i weld.

I really hope ur joking man?!?

Have you never heard of a vice grip LOL?

[fizzissist]

Thats why they have carbide faces, and i have never seen one chipped from this.
I use mine to hold material together while i weld.

I concur. By dragging the mic, if you drag it towards a larger dimension, the mic can perform a number of bonus functions.
1. The carbide faces can scrape surplus material from the part, bringing it into tolerance.
2. The polished carbide faces can burnish the material, improving surface finish.
3. With some materials, the burnishing can work harden the material, eliminating costly 2nd operations.
4. With sufficient effort or use in this way, the anvil can be splayed so that the surfaces of the anvil and spindle are not parallel as they were from the factory that was too cost conscious to spend the extra money to splay them for the end user. Parallel faces are an endless problem for skilled machinists and QC people
5. A major benefit to sliding the mic across the work as it's being measured is the assurance that you're getting a good, reliable, consistent, and accurate measurement.
6. My favorite reason for using the sliding method is that it is an ingenious way of impressing skilled machinists who know what the F@@k they're doing.
7. Mitutoyo, Starret, B&S, and the other major mfg's of metrology tools ALL highly recommend this method. In fact, they recommend you have at least 8 micrometers in your toolbox for this.

I hadn't thought about using them for welding clamps.... GREAT idea!!!! It made me realize that there are countless uses for mics....like when you run out of staples and you need to hold a bunch of papers together? OR.... you can also use them as INSIDE mics...(betcha never thought of that!).... pressing grommets together.... There's a host of uses...

But... what's with all the stupid lines and numbers?? And that stupid 40pitch thing.... dumb, dumb, dumb.

(personally, in reality.... I NEVER EVER let ANYONE use my measuring tools. EVER.. I let you use my wife before I let you touch my calipers. ... this discussion is why)

[5axisguy]

My carbide face Starrett mic has been dragging off rounds and flats for the past 25 years, I have yet to see any wear on the faces, if your reaching in a machine for a measurement it's just not practical to take a reading with the mic on the piece in many instances.

[gordo.hogan]

Treat your mics like you treat your lady, Gently. And then you wont have wear on them. Im pretty sure they are made for sliding.

As my mentor always used to tell me, "Its not a G-clamp "

[fizzissist]

My carbide face Starrett mic has been dragging off rounds and flats for the past 25 years, I have yet to see any wear on the faces, if your reaching in a machine for a measurement it's just not practical to take a reading with the mic on the piece in many instances.

Yes, there are cases where you need a reading in situ. I openly admit that there have been times where I haven't been able to see the reading, and have had to lock it and drag.... I still maintain it's bad practice.

[UUU]

I always used to drag before reading. But that was with conventional or vernier mics. Trying to read tenths with the thing still clamped on the part just wasn't easy.

But now I've gone digital, I can read the figure much more easily.

So I drag it off after the reading.

[underthetire]

I really hope ur joking man?!?

Have you never heard of a vice grip LOL?

Sort of..
Some tooling vendor gave me a Chinese 0-1 mic as a gift. I have my old Mititoyos from ~1986, no friction or ratchet thimble on those babies. Love them. Anyways, just to see the look on my old bosses face, i clamped a couple pieces of stainless together right in front of him and walked over to the TIG bench and stuck them together. He just sat there and watched in dis-belief. Then i walked back, pulled a part off the lathe and checked it with the same MIC. I thought he was going to throw up.

[RICHARD ZASTROW]

The carbide faces install that wonderful engraving on the hard chrome 1 micron surfaces too.LOL

Dick Z

[christinandavid]

You should never be able to drag the mic off the part. A good rule of thumb to use is that if you can drag the mic off the part then it isn't clamping the part tight enough...thats why measuring with very large mics is such a fine art.

DP

[packrat]

You should never be able to drag the mic off the part. A good rule of thumb to use is that if you can drag the mic off the part then it isn't clamping the part tight enough...thats why measuring with very large mics is such a fine art.

DP

Hope you don't make parts that have to fit with some one else's parts. If it won't slide its too tight.

[christinandavid]

I always calibrate my mics +.002 x ((mic upper limit + mic lower limit)/2) to compensate for the flex. That way my measuring technique always gives the correct results. It's also good practice to stone a convex radius onto the anvils to ensure point contact regardless of the angle of flex.

DP

[packrat]

I always calibrate my mics +.002 x ((mic upper limit + mic lower limit)/2) to compensate for the flex. That way my measuring technique always gives the correct results. It's also good practice to stone a convex radius onto the anvils to ensure point contact regardless of the angle of flex.

DP

Hope this is just Kiwi humor

[christinandavid]

Another bonus is that the "hammered" finish left on the part makes it easy to identify the features I have personally inspected.

DP

[fizzissist]

Anyone here taken a properly calibrated mic, cleaned the faces properly, measured a properly cleaned gage block....locked the mic down and dragged it off the block???

Lemme know what you observe...