[christinandavid]

Will get back to you as soon as my measuring equipment is cool enough to handle (have purged it with oxy flame to remove any contaminants). I would quench it all to speed up the process but I don't fancy picking the slips out of the oil vat.

DP

[dertsap]

My preference is not to use the lock on the mic and only use it when I absolutely need to , quite often the lock will knock the measurement out .0002 , I've seen it far too often with different mic's over the years while setting bore guages , Mitutoyo seems particularly bad for it

[txcncman]

Or...you can just you your mics as paperweights to hold prints down so the shop fan does not blow them away and call the QC guy over to measure all of your parts for you.

[dertsap]

Or...you can just you your mics as paperweights to hold prints down so the shop fan does not blow them away and call the QC guy over to measure all of your parts for you.

who's that comment directed at ?

[holbieone]

on the 4th i used them to pop some caps off . they pop around .00472 , but you gotta spin it quick

[txcncman]

who's that comment directed at ?

Since it did not include your name it was not directed at you. Are you so smart as to think that if a post immediately follows your post that the new post is a direct result of your post? Do you think you trigger every event that happens in the world?

[dertsap]

Since it did not include your name it was not directed at you. Are you so smart as to think that if a post immediately follows your post that the new post is a direct result of your post? Do you think you trigger every event that happens in the world?

nothing like a simple answer to a simple question now is there you ignorant know it all know nothing pos , it must have been directed towards someone . it seems to keep in track of worthless posts that you pollute these forums with , if it isn't your typical ignorant remarks , then it's to answer a question with a question rather than to offer a solution (which it's clear that your incapable of )




.

[txcncman]

nothing like a simple answer to a simple question now is there you ignorant know it all know nothing pos , it must have been directed towards someone . it seems to keep in track of worthless posts that you pollute these forums with , if it isn't your typical ignorant remarks , then it's to answer a question with a question rather than to offer a solution (which it's clear that your incapable of )




.

Let me simplify for you. No, my comment was not directed at you.

Again, I have been shown the error of my ways by one so much greater than myself. Your intelligence (or lack there of) leaves me speechless. Good day.

[JWH]

I use my mic to set up my bore gage when I don’t have a ring gage close. I assemble gage blocks to the dimension needed, set the mic to the gage blocks, lock it and slide it off. Then use the mic to set the bore gage.

Jim

[christinandavid]

Good thinking JWH. I'm having difficulty wringing my slips together at the mo after purging them, even though I made sure I stoned them to remove any scale residue..

Thought it might be interesting to hear thoughts on internal mic measuring techniques. I personally have developed a method I call "score the bore". I basically set the mic to bottom limit (be sure to double check against a good external mic) and then pass it through the semi-finished bore. Don't worry the mic will centralize itself as you pull it through. It will leave a gouge. Continue machining until gouge is removed and voila, you have achieved size.

DP

[tmcallister74]

Good thinking JWH. I'm having difficulty wringing my slips together at the mo after purging them, even though I made sure I stoned them to remove any scale residue..

Thought it might be interesting to hear thoughts on internal mic measuring techniques. I personally have developed a method I call "score the bore". I basically set the mic to bottom limit (be sure to double check against a good external mic) and then pass it through the semi-finished bore. Don't worry the mic will centralize itself as you pull it through. It will leave a gouge. Continue machining until gouge is removed and voila, you have achieved size.

DP

^^^ This guy. I'm laughing so hard I wet myself.

[allthumbz]

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

Is it possible that they are afraid to lose the reading if they open the mic up again?


Just a thought.



Nelson

[Mcgyver]

Thats why they have carbide faces, and i have never seen one chipped from this.
I

+1 and I've handled hundreds.

A very good reason for removing the mic for reading is to have a proper view position and light and to eliminate parallax error; especially if looking at the tenths vernier.

[allthumbz]

Is the clamping pressure placed on the workpiece supposed to be so tight that it cannot move and the ratchet slips, or it is supposed to be just tight enough so the barrels of the mic make contact, or something else? Some of the posts here seem to indicate both.

Which is correct?

Thanks,


Nelson

[christinandavid]

If the barrels make contact then that MUST surely be over-tight as it means you have punched all the way through.

Since moving onto horizontals I have found an advantage over vertical setups. You can GUARANTEE consistent torque of your mics while working perpendicular to gravity - simply hang weights off the mic (This, in case you are unaware, is the purpose of the series of holes through the body of the mic) and record the point at which the mic starts to move. With practice you can set ANY size mic to slip at a certain point, and you are on the way towards ultimate accuracy.

DP

[allthumbz]

If the barrels make contact then that MUST surely be over-tight as it means you have punched all the way through.

Contact with the workpiece, not with each other...



Nelson

[handlewanker]

Hiiiyyyyy guys, having spent the last 50 years or so hacking metal, it occured to me that there must be hundreds if not thousands of parts in existance that I made that got measured by clamping, squeezing or sliding the mic' faces on the parts, and not one of them was ever returned as not to drawing or out of tolerance.

So who is right....nobody.

In a test that was carried out at random a number of tool makers were given a mic and asked to measure a gauge block pack without knowing the size of the blocks.

Needless to say they all got different results.

Personally I always use the mic barrel ratchet....you can't overtighten the ratchet or have it too loose......no two people have the same feel with a mic.

Incidently, when you are using a go/no go slip gauge, when is the part correct......when the gauge can be slid off the job easily at top limit or must it be firm on the job......same as for bottom limit.....tight or loose?

I would go further and state that it is impossible to measure a job to within .0005" (half a thou) without proper measuring equipment, and that ain't a hand held micrometer, and you can forget it too if the temperature of the day is either freezing cold or boiling hot.......that's precision B/S to impress the noobs.
Ian.

[underthetire]

Is the clamping pressure placed on the workpiece supposed to be so tight that it cannot move and the ratchet slips, or it is supposed to be just tight enough so the barrels of the mic make contact, or something else? Some of the posts here seem to indicate both.

Which is correct?

Thanks,


Nelson

Depends on who calibrated them. I have a light touch, as the micrometer will dig in to some materials. I always had to adjust mine after they were calibrated.

[christinandavid]

Incidently, when you are using a go/no go slip gauge, when is the part correct......when the gauge can be slid off the job easily at top limit or must it be firm on the job......same as for bottom limit.....tight or loose?

I was always told by inspection department that size-on-size won't go. You should always allow for this when tolerancing your gauge, or it could reject a good part.

My personal preference is to always tap with a hammer to make doubly sure. Extra skill and caution is required at this point though; gauge MUST be perfectly square before hammering commences.

DP

[allthumbz]

Depends on who calibrated them. I have a light touch, as the micrometer will dig in to some materials. I always had to adjust mine after they were calibrated.

How do you make that adjustment?


Nelson