# Chinese precision levels



## 682bear (Mar 1, 2021)

Does anyone have any experience with the chinesium precision levels? I just acquired this...




It was a freebie... it seems to be well made, but I'm not sure about the accuracy.

The 'instructions' were with it, I guess... 

I say 'I guess' because it is all written in chinese... so I'm only assuming it is instructions...

Any info is appreciated, good or bad.

-Bear


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## RJSakowski (Mar 1, 2021)

Not the same level but I have no complaints about my level.  Levels are self proving instruments.  There are two concerns with a precision level.  One is how true are the surfaces; flatness and squareness, in your case.  The other is sensitivity.  

Checking a level like yours will require a means to measure squareness of adjacent surfaces and parallelness of the opposing surfaces.  You can check sensitivity by shimming a bar that the level is resting on.


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## silence dogood (Mar 1, 2021)

Place the level on a flat surface such as a mill table.  Take a known dimension shim such as a feeler gauge and put on one side.  When the bubble moves from one line to the next, you now have an idea of how accurate it is.


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## Neurotic-Hapi-Snak (Mar 1, 2021)

Definitely verify parallelism and squareness, one member on here hade one of those and although it was parallel within a few tenths the squareness was off by over .010"


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## BGHansen (Mar 1, 2021)

Maybe look at a bubble reading and note the position.  Flip it 180 and it should be in the same spot on the opposite side of the center line of the vial.  If it's not, half the difference is the inaccuracy.  Same check as a carpenter's square, set it on an edge and trace a line on the other leg.  Flip the square over and repeat.  If it's a "V", it's out of square by half.

The shim idea above is really good for checking the sensitivity/graduations on the vial.  Piece of paper is about 0.003".

Bruce


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## Masterjuggler (Mar 1, 2021)

I made a thread a month ago where I checked the accuracy of some chinesium level vials, and found them to be spot on: https://www.hobby-machinist.com/threads/cheapo-level-vials-are-accurate.90212/

Like others have said though, you'll have to check the frame for parallelism and squareness. All you need for that is a surface plate and a dial indicator with a base. Oxtoolco has some pretty good videos about doing that, like this one:


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## The Shootist (Mar 3, 2021)

When working with high accuracy levels you should set the level down and let it "settle" for a while. The more accurate levels have near zero curve to the vial and may take a while to respond. Even "spirit" levels where the fluid is alcohol take a few minutes to fully resolve accurately.


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## porthos (Apr 4, 2021)

_i belive that the term chinese and precision is a oxymoron, from my experiences_


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