Yesterday I did a comparison between my newly acquired second hand Mitutoyo 1 – 2” micrometer and a cheap C#!ne$e micrometer. Don’t know how old the Mitutoyo is, but as it came in a plastic box I presume it isn’t vintage and veteran. The Cheapy C#!ne$e 25 – 50mm micrometer I bought in 1993 when I was in Malaysia and it came in a wooden box with test bar and spanner.
To start, I zeroed each with it’s test bar, then I measured the Mitutoyo 1” test bar with the Cheapy, the reading was exactly 25.4mm. I couldn’t measure the cheapies test bar with the Mit properly as the Mit’s dial starts at 1” or 25.4mm; however I did turn the thimble in past the zero on the barrel. The reading was between graduations 0.015”/0.016”, or just a shade under 0.016”
Next I measured a 50mm test bar with both micrometers, the readings were: Mitutoyo – 1.968”, exact; cheapy – 50.00mm,.again exact.
Now if the Cheapy and the Mitutoyo are spot on at 1” and also at 50mm, there is no reason to expect they would differ somewhere in between, but to satisfy myself I searched for something to use that was in between, and settled on a bearing as bearings are usually pretty accurate.
I measured the bearing using the Mitutoyo and the cheapy at three points around it’s circumference and could find no discrepancy with the readings on either micrometer. The readings were: Mitutoyo - 1.377, exact; cheapy - 34.98, also exact.
I also tested for repeatability (in a fashion) simply by removing the item, spinning the barrel and re-measuring again three times with each measurement and noticed no discrepancies.
Then we have temperature. My workshop isn’t temperature controlled; but, the tests were done within minutes of each other so I don’t think temperature variance would have played a significant part with the results - but you never know!
Occasionally the graduation lines on the thimble may have been slightly out of alignment with that of the barrel graduation lines, but we’re talking about measurement that are well beyond the scope of either the Mit or the cheapy.
Comparing the measurement of the cheapy and the Mit did prove a little time consuming, mainly because the Mit was in imperial, whereas the cheapy in metric. So, I resorted to the use of a calculator using 25.4mm per inch as a datum. I researched that number everywhere but couldn’t come up with a finer decimal figure than 25.4. Of course, with the different measurement systems, sometimes the readings could reasonably be expected to be somewhere between graduations, for this test, only once: the 25mm test rod test. still I think that accurate enough.
Next I stripped both down for a look see, both were very similar in design, the cheapy being heavier in manufacture: the cheapies frame was considerably heftier than the Mit and some of the threaded fittings were also of a larger size, namely the screw at the end of the ratchet thimble, the ratchet axle post and the main spindle.
Under a loupe, I looked at the business end of both - the actual spindle thread. Whilst obviously a different pitch, the cheapy being a finer thread, I couldn’t see any flaws in the thread of either and both spun freely without any noticeable binding, Of course I have heard it said that would be the norm for Mitutoyo anyway.
The only flaws I could find on the cheapy were the finish on the ratchet axle was not quite as ‘smooth’ as the Mit. I’d also have to say the paint finish on the cheapy isn’t as good as the Mit. That of course is evidenced by the chipped paint on the cheapies frame. The Mits frame had no discernible chips. The damage on the cheapy being caused by being knocked off the workbench, chipping the paintwork and scratching the thimble a little. Of course, I’m in no doubt, the Mit’s paint wouldn’t have chipped at all had it been dropped from the same height.
Given the results, you could (arguably) say the cheapy is every bit as accurate as the Mitutoyo. And given the age of the cheapy (1993), the reasonably frequent useage and the accidental damage it sustained from being dropped on the floor, I’d suggest the expected longevity and the build quality, at worst, are pretty darn good.
Normally, all my measuring instruments live between two pieces of oiled carpet in an oiled wooden draw, so they are pretty much in the same condition as they were when new - save for the chip, so I suppose at a stretch, you could say the cheapy is either a one off or it has been spoilt - maybe, just maybe, but I think you’d be clutching at straws there.
I paid RM18 (approx $Aust10) for that particular micrometer at a tool shop on Penang Island, where at various times I also bought a 50/75mm and a 75/100mm micrometer for much the same price, a B&D drop saw (RM300) and three boxes of cut off wheels (150 wheels for RM50) and a couple of other bits and pieces. The exchange rate during my time there was around 1.70 - 1.90, so everything was very, very cheap.
Taiwanese tools were the go in Australia in the early 90s; however, in Malaysia, that wasn’t the case. Tools made in Taiwan weren’t evident, presumably because a large percentage of Malaysia’s population were C#!ne$e - and Indian of course. Certainly all the tool shop owners I dealt with were C#!ne$e - Malays tended towards cafes and Government employment and the like. So based on that I’d say the cheapy micrometer is definitely C#!ne$e.
If anyone else has done a like test, I’d be interested in the outcome.
To start, I zeroed each with it’s test bar, then I measured the Mitutoyo 1” test bar with the Cheapy, the reading was exactly 25.4mm. I couldn’t measure the cheapies test bar with the Mit properly as the Mit’s dial starts at 1” or 25.4mm; however I did turn the thimble in past the zero on the barrel. The reading was between graduations 0.015”/0.016”, or just a shade under 0.016”
Next I measured a 50mm test bar with both micrometers, the readings were: Mitutoyo – 1.968”, exact; cheapy – 50.00mm,.again exact.
Now if the Cheapy and the Mitutoyo are spot on at 1” and also at 50mm, there is no reason to expect they would differ somewhere in between, but to satisfy myself I searched for something to use that was in between, and settled on a bearing as bearings are usually pretty accurate.
I measured the bearing using the Mitutoyo and the cheapy at three points around it’s circumference and could find no discrepancy with the readings on either micrometer. The readings were: Mitutoyo - 1.377, exact; cheapy - 34.98, also exact.
I also tested for repeatability (in a fashion) simply by removing the item, spinning the barrel and re-measuring again three times with each measurement and noticed no discrepancies.
Then we have temperature. My workshop isn’t temperature controlled; but, the tests were done within minutes of each other so I don’t think temperature variance would have played a significant part with the results - but you never know!
Occasionally the graduation lines on the thimble may have been slightly out of alignment with that of the barrel graduation lines, but we’re talking about measurement that are well beyond the scope of either the Mit or the cheapy.
Comparing the measurement of the cheapy and the Mit did prove a little time consuming, mainly because the Mit was in imperial, whereas the cheapy in metric. So, I resorted to the use of a calculator using 25.4mm per inch as a datum. I researched that number everywhere but couldn’t come up with a finer decimal figure than 25.4. Of course, with the different measurement systems, sometimes the readings could reasonably be expected to be somewhere between graduations, for this test, only once: the 25mm test rod test. still I think that accurate enough.
Next I stripped both down for a look see, both were very similar in design, the cheapy being heavier in manufacture: the cheapies frame was considerably heftier than the Mit and some of the threaded fittings were also of a larger size, namely the screw at the end of the ratchet thimble, the ratchet axle post and the main spindle.
Under a loupe, I looked at the business end of both - the actual spindle thread. Whilst obviously a different pitch, the cheapy being a finer thread, I couldn’t see any flaws in the thread of either and both spun freely without any noticeable binding, Of course I have heard it said that would be the norm for Mitutoyo anyway.
The only flaws I could find on the cheapy were the finish on the ratchet axle was not quite as ‘smooth’ as the Mit. I’d also have to say the paint finish on the cheapy isn’t as good as the Mit. That of course is evidenced by the chipped paint on the cheapies frame. The Mits frame had no discernible chips. The damage on the cheapy being caused by being knocked off the workbench, chipping the paintwork and scratching the thimble a little. Of course, I’m in no doubt, the Mit’s paint wouldn’t have chipped at all had it been dropped from the same height.
Given the results, you could (arguably) say the cheapy is every bit as accurate as the Mitutoyo. And given the age of the cheapy (1993), the reasonably frequent useage and the accidental damage it sustained from being dropped on the floor, I’d suggest the expected longevity and the build quality, at worst, are pretty darn good.
Normally, all my measuring instruments live between two pieces of oiled carpet in an oiled wooden draw, so they are pretty much in the same condition as they were when new - save for the chip, so I suppose at a stretch, you could say the cheapy is either a one off or it has been spoilt - maybe, just maybe, but I think you’d be clutching at straws there.
I paid RM18 (approx $Aust10) for that particular micrometer at a tool shop on Penang Island, where at various times I also bought a 50/75mm and a 75/100mm micrometer for much the same price, a B&D drop saw (RM300) and three boxes of cut off wheels (150 wheels for RM50) and a couple of other bits and pieces. The exchange rate during my time there was around 1.70 - 1.90, so everything was very, very cheap.
Taiwanese tools were the go in Australia in the early 90s; however, in Malaysia, that wasn’t the case. Tools made in Taiwan weren’t evident, presumably because a large percentage of Malaysia’s population were C#!ne$e - and Indian of course. Certainly all the tool shop owners I dealt with were C#!ne$e - Malays tended towards cafes and Government employment and the like. So based on that I’d say the cheapy micrometer is definitely C#!ne$e.
If anyone else has done a like test, I’d be interested in the outcome.
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