- Joined
- Mar 25, 2013
- Messages
- 4,614
This seem crazy. I bought these 4" Mitutoyo calipers brand new from Amazon about a year ago:
I have been having a lot of trouble fitting shafts into bearings recently and I could not figure out why. I was having to give the bearing extra clearance by trial and error to make it fit. It thought I was doing something wrong but I could not figure it out.
Finally I decided to check my calipers. On a precision ground .750 shaft the Mitutoyo reads 0.745. My cheap-ass Northern tool caliper reads .749. Even more distressing is that the inside and outside calipers are ground wrong and do not agree.
Here's how it tested this. Tell me if this is not valid. I put the Norther Tool caliper on the shaft and got a reading of .749 and locked it at that setting. The Mitu reads .745 on that shaft. I then put the inside calipers of the Mitu inside the blades of the Northern and got a reading of .751.
Conclusion: There is .006 difference between the grind of the inside and outside calipers of the Mitucrapo. The Mitucrapo is also calibrated incorrectly for OD.
I am really displeased after spending this kind of money on a caliper. I should have caught this sooner when I could return it but it took me a year to figure it out. I should note that the device has never been dropped damaged or used as a pry bar.
What are your thoughts on this? The device is junk unless Mitutoyo will replace it. What is their warranty and has anyone used it?
Robert
I have been having a lot of trouble fitting shafts into bearings recently and I could not figure out why. I was having to give the bearing extra clearance by trial and error to make it fit. It thought I was doing something wrong but I could not figure it out.
Finally I decided to check my calipers. On a precision ground .750 shaft the Mitutoyo reads 0.745. My cheap-ass Northern tool caliper reads .749. Even more distressing is that the inside and outside calipers are ground wrong and do not agree.
Here's how it tested this. Tell me if this is not valid. I put the Norther Tool caliper on the shaft and got a reading of .749 and locked it at that setting. The Mitu reads .745 on that shaft. I then put the inside calipers of the Mitu inside the blades of the Northern and got a reading of .751.
Conclusion: There is .006 difference between the grind of the inside and outside calipers of the Mitucrapo. The Mitucrapo is also calibrated incorrectly for OD.
I am really displeased after spending this kind of money on a caliper. I should have caught this sooner when I could return it but it took me a year to figure it out. I should note that the device has never been dropped damaged or used as a pry bar.
What are your thoughts on this? The device is junk unless Mitutoyo will replace it. What is their warranty and has anyone used it?
Robert