- Joined
- Apr 8, 2021
- Messages
- 138
inverse to the apollo program, everything in metrixc and later in imperial
-
Welcome back Guest! Did you know you can mentor other members here at H-M? If not, please check out our Relaunch of Hobby Machinist Mentoring Program!
Buying new micrometers
- Thread starter Alberto-sp
- Start date
- Joined
- Apr 23, 2018
- Messages
- 6,520
All measuring systems are the same, it just depends on what keystrokes you hit on the calculator or what you scribble down on paper to make them line up. It's all arbitrary, except for the metric system! That's actually based on real-world numbers.
Back in NASA's Pioneer 10 project, they fixed a gold-plated plaque on the spacecraft for aliens to read. It was based on binary information and the natural resonance of the hydrogen gas molecule (a universal constant that defines a time period and therefore a finite distance at the speed of light), and the relationship/periodicity of the known pulsars. Now that's a measuring system!
Back in NASA's Pioneer 10 project, they fixed a gold-plated plaque on the spacecraft for aliens to read. It was based on binary information and the natural resonance of the hydrogen gas molecule (a universal constant that defines a time period and therefore a finite distance at the speed of light), and the relationship/periodicity of the known pulsars. Now that's a measuring system!
- Joined
- Apr 8, 2021
- Messages
- 138
Hi.
One question. Is it very important that the dial of the test indicator will be smooth (To adjust it to 0) or the way to put it at 0 is with the adjustment screw in the test indicator holder?
I ask because mine is a little bit hard.
By the way, I have been to Germany in holiday and in the Deuchstes Museun in Munich (Awsome place) I see that. The definitive tool!
It has a window and a light to check that the vernier scale is paralell to the main scale.
One question. Is it very important that the dial of the test indicator will be smooth (To adjust it to 0) or the way to put it at 0 is with the adjustment screw in the test indicator holder?
I ask because mine is a little bit hard.
By the way, I have been to Germany in holiday and in the Deuchstes Museun in Munich (Awsome place) I see that. The definitive tool!
It has a window and a light to check that the vernier scale is paralell to the main scale.
- Joined
- Apr 20, 2019
- Messages
- 166
When I started doing AutoCAD drafting, I remember asking the conversion from inches to millimetres- 25.4, exactly… I thought, surely there must be some sort of rounding.
It was probably 20 years before I read a historical book on measurements and it went through the fascinating evolution of measurement systems. There were several different measurements for inches and the decision was made to standardize and make them all equal to 25.4mm, exactly…
I do find inches a nice size unit, though I really don’t like fractions. millimeters are getting a bit hard on my eyes. I have one decimal ruler, but have to be careful not to mix the tenths of an inch up with eighths of an inch.
Ebay is a good place to pick up quality name brand micrometers and indicators at a good price.
All it takes is time to look and have patience, metric metrology instruments aren't the most plentiful on ebay, especially in USA.
But there are some real bargains to be had.
30+ years ago I bought a Vis 0-25mm micrometer and have used it often, it has a friction thimble and has a real silky smooth feel, I often wished I'd bought the 25-50, 50-75 & 75-100mm, recently I picked all those up on ebay, all new in the box for less than I paid for my 0-25mm.
Insize are sold here in New Zealand and I've tried a few of their micrometers and they don't feel as smooth as my Vis or Mitutoyo micrometers.
As above there is no difference between mm and imperial that a good calculator won't fix.
All it takes is time to look and have patience, metric metrology instruments aren't the most plentiful on ebay, especially in USA.
But there are some real bargains to be had.
30+ years ago I bought a Vis 0-25mm micrometer and have used it often, it has a friction thimble and has a real silky smooth feel, I often wished I'd bought the 25-50, 50-75 & 75-100mm, recently I picked all those up on ebay, all new in the box for less than I paid for my 0-25mm.
Insize are sold here in New Zealand and I've tried a few of their micrometers and they don't feel as smooth as my Vis or Mitutoyo micrometers.
As above there is no difference between mm and imperial that a good calculator won't fix.
@Alberto-sp I found a couple of options for micrometers on Ebay and a real good indicator
0-25mm Mitutoyo 0.001mm friction thimble
another option 0-25mm Mitutoyo 0.001mm rachet thimble
25-50 Brown & Sharpe 0.001mm with friction thimble
One of the best indicators you can buy
Use MyUS for shipping and you can get them to combine everything into one parcel.
Kiwi
0-25mm Mitutoyo 0.001mm friction thimble
MITUTOYO 102-123 OUTSIDE MICROMETER RANGE: 0 TO 25MM RESOLUTION: 0.001MM | eBay
Find many great new & used options and get the best deals for MITUTOYO 102-123 OUTSIDE MICROMETER RANGE: 0 TO 25MM RESOLUTION: 0.001MM at the best online prices at eBay! Free shipping for many products!
www.ebay.com
another option 0-25mm Mitutoyo 0.001mm rachet thimble
Mitutoyo - 0-25mm 0.001mm - No.102-307 Made in Japan | eBay
Find many great new & used options and get the best deals for Mitutoyo - 0-25mm 0.001mm - No.102-307 Made in Japan at the best online prices at eBay! Free shipping for many products!
www.ebay.com
MITUTOYO 101-115 M225-M25 OUTSIDE MICROMETER RANGE 0 - 25mm RESOLUTION: 0.001mm | eBay
Find many great new & used options and get the best deals for MITUTOYO 101-115 M225-M25 OUTSIDE MICROMETER RANGE 0 - 25mm RESOLUTION: 0.001mm at the best online prices at eBay! Free shipping for many products!
www.ebay.com
25-50 Brown & Sharpe 0.001mm with friction thimble
Brown & Sharpe 25-50mm Straight Line Micrometer | eBay
25-50mm by. 002mm. We Have 8 Available.
www.ebay.com
One of the best indicators you can buy
BESTEST METRIC DIAL TEST INDICATOR .01mm LARGE FACE 7031-13 NO ENGRAVINGS | eBay
Find many great new & used options and get the best deals for BESTEST METRIC DIAL TEST INDICATOR .01mm LARGE FACE 7031-13 NO ENGRAVINGS at the best online prices at eBay! Free shipping for many products!
www.ebay.com
Use MyUS for shipping and you can get them to combine everything into one parcel.
Kiwi
- Joined
- Apr 8, 2021
- Messages
- 138
@Alberto-sp I found a couple of options for micrometers on Ebay and a real good indicator
0-25mm Mitutoyo 0.001mm friction thimble
MITUTOYO 102-123 OUTSIDE MICROMETER RANGE: 0 TO 25MM RESOLUTION: 0.001MM | eBay
Find many great new & used options and get the best deals for MITUTOYO 102-123 OUTSIDE MICROMETER RANGE: 0 TO 25MM RESOLUTION: 0.001MM at the best online prices at eBay! Free shipping for many products!www.ebay.com
another option 0-25mm Mitutoyo 0.001mm rachet thimble
Mitutoyo - 0-25mm 0.001mm - No.102-307 Made in Japan | eBay
Find many great new & used options and get the best deals for Mitutoyo - 0-25mm 0.001mm - No.102-307 Made in Japan at the best online prices at eBay! Free shipping for many products!www.ebay.com
MITUTOYO 101-115 M225-M25 OUTSIDE MICROMETER RANGE 0 - 25mm RESOLUTION: 0.001mm | eBay
Find many great new & used options and get the best deals for MITUTOYO 101-115 M225-M25 OUTSIDE MICROMETER RANGE 0 - 25mm RESOLUTION: 0.001mm at the best online prices at eBay! Free shipping for many products!www.ebay.com
25-50 Brown & Sharpe 0.001mm with friction thimble
Brown & Sharpe 25-50mm Straight Line Micrometer | eBay
25-50mm by. 002mm. We Have 8 Available.www.ebay.com
One of the best indicators you can buy
BESTEST METRIC DIAL TEST INDICATOR .01mm LARGE FACE 7031-13 NO ENGRAVINGS | eBay
Find many great new & used options and get the best deals for BESTEST METRIC DIAL TEST INDICATOR .01mm LARGE FACE 7031-13 NO ENGRAVINGS at the best online prices at eBay! Free shipping for many products!www.ebay.com
Use MyUS for shipping and you can get them to combine everything into one parcel.
Kiwi
Thank you very much!!