Inside Dial Gauge

[ctwo]

I have an MSC dial gauge just like in this video. The first 90 seconds will illustrate some very confusing info, specifically the even and odd side of the gauge. What is this man trying to say here

https://www.youtube.com/watch?v=lyoEtXPwCkw

My gauge covers 0.375 to 1.375 just like the one in the video. What perplexes me is that I can set a zero, but then when I measure a micrometer set to one inch, the gauge reads 0.600. The coarse needle ranges from 1 to 0, so if I set my mic to 1.375, the gauge does compress about 17 thou and the fine dial reads 75 thou. But if I read the entire dial, it's telling me 0.975.

A similar gauge in the video below makes perfect sense. It ranges from 5 to 15 mm, and when they set a zero using a 4.9990 standard, the coarse and fine needles point to 5 and 0, respectively.

https://www.youtube.com/watch?v=0zzQpzOG20w

Now that makes me wonder if the coarse needle on my gauge should not instead be labeled 1.4 to 0.4. Why would they label it 0 to 1? They all seem to be that way, except the fancy, stupidly expensive ones, i.e., both of these are SPI:

https://www.mscdirect.com/product/details/88094545

https://www.mscdirect.com/product/details/67947226

Also, what is the material that makes up the contact balls? When I first saw that I thought the contact anvil had a dab of glue or paint, and I thought it needed to be picked off. Seems like hard stuff and I realize its intent.

[ctwo]

I have an MSC dial gauge just like in this video. The first 90 seconds will illustrate some very confusing info, specifically the even and odd side of the gauge. What is this man trying to say here


https://www.youtube.com/watch?v=lyoEtXPwCkw

My gauge covers 0.375 to 1.375 just like the one in the video. What perplexes me is that I can set a zero, but then when I measure a micrometer set to one inch, the gauge reads 0.600. The coarse needle ranges from 1 to 0, so if I set my mic to 1.375, the gauge does compress about 17 thou and the fine dial reads 75 thou. But if I read the entire dial, it's telling me 0.975.

A similar gauge in the video below makes perfect sense. It ranges from 5 to 15 mm, and when they set a zero using a 4.9990 standard, the coarse and fine needles point to 5 and 0, respectively.


https://www.youtube.com/watch?v=0zzQpzOG20w

Now that makes me wonder if the coarse needle on my gauge should not instead be labeled 1.4 to 0.4. Why would they label it 0 to 1? They all seem to be that way, except the fancy, stupidly expensive ones, i.e., both of these are SPI:

https://www.mscdirect.com/product/details/88094545

https://www.mscdirect.com/product/details/67947226

Also, what is the material that makes up the contact balls? When I first saw that I thought the contact anvil had a dab of glue or paint, and I thought it needed to be picked off. Seems like hard stuff and I realize its intent.

[GlennW]

specifically the even and odd side of the gauge. What is this man trying to say here

It's .2 per revolution, so 0-.1 on one side (odd) will be .1, .3, .5, 7, and 9, and 0-.1 on the other side (even) will be .2, .4, .6, .8.

(This is like trying to explain how to read a vernier caliper without being there and showing how...)

[ctwo]

OK, I get that. I'd just look at the coarse needle to figure out the 10ths place.

Looks like I punched the wrong button to edit my post...