Problem with 1" outside micrometer

[WSnyder]

Ha! My Nardini is diameter on the cross and radius on the compound

 

[AlNyhus]

Which brand/model do you think I should get that would give me consistently reliable measurements to .0001" recognizing there is a bit of practice and touch involved?

The Mitutoyo 293-340-30 would be worth a look. I picked this one up not long ago to use in my bullet making.

I find myself going back to the non-electronic 193-211 model as they fit my hands better. There's one here for general use and one that's dedicated as the bullet checker.

For what it's worth....

 

[jackieschmidt]

The Mitutoyo 293-340-30 would be worth a look. I picked this one up not long ago to use in my bullet making.

I find myself going back to the non-electronic 193-211 model as they fit my hands better. There's one here for general use and one that's dedicated as the bullet checker.

For what it's worth....

Al, those are what I use, but I rely on the .0001 vernier on the spindle rather than the digital numbers.

 

[AccelR8]

That 193-211 looks like an old friend! I've had one for over 30 years. Maybe close to 40. The paint is worn off the insulating pads, and they've both come off and been glued back on several times. But the rest of it, the body, the thimble and the window are all still like new. I check it against standards periodically and it still reads accurately.

My dad had given me a Starrett in 1975. When I got that Mitutoyo he had a fit and forbid me from using. I started calling it my "idiot mic" because of his objections. According to him, because it was Japanese, it was junk, inaccurate, and would soon wear even beyond it's present inaccurate condition. Starrett was the ONLY brand to be used and trusted, with Brown and Sharpe as an also-ran if you couldn't get Starrett. He told me to throw the Mitutoyo in the trash. Funny thing though, he eventually retired and later passed on and I found Mitutoyo dial test indicators in his tool box!

I still have and use the Mitutoyo. Well worth what I paid for it. I did still use the Starrett virtually every day until it disappeared a couple years ago.

 

[ELR LVR]

No love for the older Fowler stuff?
I must be the oddball, I like brands like Fowler, Tubular Micrometer CO.
and Teclock even a tiny bit more than Mitutoyo
Those Fowlers perform right there as smooth and accurate as my B&S Mics

 

[AccelR8]

No love for Fowler huh?

I have a Fowler 1-2" outside mic and a Fowler Depth mic 0-6" and they are both fine. A couple of Fowler dial indicators too, happy with them as well.

 

[Cassidy]

Thank you all very much for your informative suggestions! I just ordered a Mitutoyo 293-340-30 that Al suggested; thank you Al!

 

[RGRobinett]

I have and use 2 Mitutoyo 'digital' mics, like Jackie, when I want//need to be 'close', read the vernier, and/or, double check with the one of the 'old' Starrett mechanical micrometers. Also, at least weekly, all are checked on standard - as advised by Bill Niemi, XX gauge spec. - on .243" and .308" diameters. RG

 

[Cassidy]

Thank you, RG! I've got a 1" standard I use but will use it more frequently.

 

[rwj]

Please help me understand how using analog/mechanical micrometers, whose parts were made on CNC machines employing digital measuring instruments, is in any way better than using digital micrometers?

 

[Alan Warner]

Thank you, RG! I've got a 1" standard I use but will use it more frequently.

Use a certed standard near the size of your work piece. Good mics these days can vary .0001 or 2 over the inch of travel.
Doesn't hurt to have an optical flat on hand either.

 

[ELR LVR]

Please help me understand how using analog/mechanical micrometers, whose parts were made on CNC machines employing digital measuring instruments, is in any way better than using digital micrometers?

the readouts on the cnc machines, are common grounded, not run on batteries etc
If our handheld instruments were 110v plug in and shielded from EMF/High Freq it might be better
---
I've mentioned before, how when i ran CNC Fadal Mills, every startup would tweak my cell phone out
The screen would change, Texts would be multiple repeated but split into different sections of text order etc like a ghost was in the phone.
just weird trippy stuff I couldnt even do manually to it. in such sudden fashion.
The phone finally burned up from it., I got the same phone replacement and had to keep the phone 10 feet or so away from the mill (High Freq drives, 3 ph etc),
One of my Mitutoyo digital calipers, suddenly reads off about .600" every time I start my lathe
as if it's affected by the EMF startup of the motor
My other Mitutoyo digital caliper doesn't, so its luck of the draw and you never know which one it may affect.
So we want to use digital instruments in the machine shop, but its the machines we use that affect them.
---
they may be better now, these things may have been addressed better now, they may be less susceptible now
but....??? just saying, it HAS happened
---
With mechanical instruments, you know for a fact whats going on, especially if you have a gauge to know it is calibrated right now today

 

[Cassidy]

Alan - thanks for your suggestion to get a certified standard close to what I am measuring. Just ordered a .3 inch Mitutoyo standard ASME grade 0.

 

[Alan Warner]

Alan - thanks for your suggestion to get a certified standard close to what I am measuring. Just ordered a .3 inch Mitutoyo standard ASME grade 0.

You can buy Deltronic pins (+,- 20 mil) for around 10 bucks in any tenth increment you want in that range of size.

 

[Cassidy]

I've got the Deltronic pins, Alan. Thanks for the suggestion.

 

[tobnpr]

After turning it on, I zero it

You're cleaning the contact faces by closing them on a piece of paper and sliding it off first?
I have a digital Shars (hasn't let me down yet, and I often cross-reference with a mechanical Starrett) that will return to + a tenth- or two- if I don't do this.

 

[Cassidy]

tobnpr - I clean contact faces by running yellow microfiber cloth between the faces; not too tightly. I thought this might work better than sliding paper between them. Seems to work OK. I know sliding paper that way is in Mitutoyo instructions, but I think maybe the paper approach predates microfiber. All thoughts are welcome.

 

[Kiwishooter]

My 1" digital OD mic which I've had for about 3-4 years started doing the following. After turning it on, I zero it and back it out well beyond .3" then inward to a little over .3" to measure case neck OD without and with a bullet inserted (to get case neck tension), sometimes it will read in the .2s" when I know it should read in the .3s. It started doing this about 2 weeks ago. I changed the battery last week, but sometimes it is still doing this. I checked the voltage on the new battery and it is correct (2.99, 3.00 and 3.00 v measured 3 times). Please advise what I should do with this mic, and if a replacement is needed, please advise. Thank you for your help!

What make is the digital micrometer?

I understand your reasons for wanting a digital micrometer as picking up the micrometer stand and rotating it every time to read the 10ths scale wouldn't be ideal.

An alternative to a digital might be a Mitutoyo 106-102 micrometer, the 10ths reading is on the barrel, the spindle is non rotating and is .315" dia not .250 like most other micrometers, and no spindle lock.
I've got a set of these in metric (picture below of a 0-1")

Alternatively a Mitutoyo 293-340-30 with ratchet or 293-348-30 with friction thimble or 293-340-30Cal which is Calibrated and comes with a Nist traceable cert and has a ratchet thimble or the 293-348-30Cal with friction thimble and is calibrated, and comes with Nist tracible cert
There's no real difference in price between the non calibrated and the calibrated and ratchet vs friction is personal preference.

I like the Mitutoyo digital micromters because you can still use them with a flat battery although the measurements are .001" not 10th's but like Al I do prefer the none digital when operating one handed the digitals don't feel as "natural" in the hand and I'm probably the odd one out as I do prefer the friction thimble
Kiwi

 

[Cassidy]

Thank you, Kiwi! There are probably two most popular mics; the one I have the problem with is not a Mitutoyo. The replacement is. The Mitutoyo 106-102 you suggested is a great idea.

 

[WesG260]

MIT... fat spindle? Non rotating'?

I use Mit's ... 1 to 2" for the most part ... if it matters I drag out the Etalons, 1 to 4" ... yeah, they get checked on the blocks ... to entertain myself...