On the Level

The individual parts are precision made and assembled to tight tolerances, and they employ a high level of quality assurance.

It's no more complicated than that.

Regards, Greg

Hi

As you know Precision Enginner's Level ( Or Mechnics level ) are used for precision Levelling of Surface Plates, Machine Tools, Machinery, Assemblies , sole plates ,shafts and many such Equipment. These Levels are graded according to the sensitivity of Bubble in Glass Vial and are of the order of 0.01 mm / Meter , 0.02 mm / meter or 0.05 mm / meter.

These Glass vials are precision Ground inside the tube having radius of curvature which are usually large, air bubble in the Tube becomes sensitive to the inclination due to the large radius. Glass vials have graduations on outside of the tube which shows the inclination. Bubble remaining in the center indicates equipment is levelled almost to Eart'hs horizon and dispacement on either side indiactes the inclination depending on which marking the edge of bubbel touches

This vials are housed in usually Cast Iron / Aluminum housing base of which are precision scrapped/ ground or lapped to high degree of flatness . Bottom face also have 120 degree V Groove / Seating face to facilaitate placement of Level Body on Cylindrical shafts for levelling. Inclination of glasss vial in the level housing is adjusted and factory set and these arrangements are conceled to avoid any temporing and setting is a very precise job and has to be done using proper calibration system.

Though Cross vials are also provided in the Level Body hey are not highly sensitive and for roughly levelling in cross direction.

Level Body are provided with Heat Insulating material to avoide transfer of body Heat while handling the level in operation.

Similarly Square frame levels are also available which can be used for checking squareness of the membersof machine Tools or any such equipment.

Degree of accuracy and precision are supposed to be of high order as these levels are important artifacts for achieving precision in levelling. Besides Starrett there are many other reputed make in world. You would find this product on website www.microflatindia.com

Trust this information would be adequate to satisfy you.

Udayan

udayan121049@yahoo.co.in

Precision manufacturing is the key.

I was wondering if the tube bent on a radius can be replaced with a straight but bulging tube. In this manner it can be used any side up to allow for different surfaces.

Dear Mr Handrik,

Tube Bent to a large radius can not be replaced. For Precision Levels it is imperative to have high sensitivity so they are ground inside using a special machine to get the Radius.

Out side of tube which is cylindrical and not bulged is graduated to read the inclination. Thre are very few producers of Vials for Precision levels . Almost all Precision Level manufacturers buy from producers of Ground vials.

Udayan

Let me ask a daft question ; I know that various devices are floated on mercury to achieve a level orientation. Is this principle employed in any portable level ? Some sort of arrangement whereby mercury partially fills a tube and is in contact with carbon resistor strip(s) to give a variable electronic output . Be kind in your savaging of my ignorance !

Hi !!!

Though I have no personal experiance of using mercury in Precision Level but I understand some Laboratory in India tried to work on this arrangementbut have not succeeded so far. Other than that I have no idea on this.

Buuble in the standard vials is craeated by filling the fluide in the tune in right qualtity. This may not be possible with Mercury.

However Electronic levels are available in Market ( Faderal -- US / Wyler -- Swiss & Talyvel-- UK ) which has a pendulum ( Disc ) suspended in the center of the housing which is always remans in vertical Direction regardless of any tilt on the housing.

I case of system in perfect levelled condition captive field across the pendulum ( Disc is same on either side,Slight amount of tilt on the surface on which level is kept would create diff in captive field across the pendulum on either side which is checked and bridge circuit and results are displayed either onAnanlog mode or digital mode

For more details you may visit website of above make Electronic levels.

If any one has experiance of using mercury in glass vial I would like to know more about this.

However I have used mercury for checking co planarity of four platform top located ata distance of 10 Meter . Mecury was fillled in flexible plastic tube with Four Cups attached at free end and these cup were interconnected with plastic tube wioth mercury in it. For taking the readings of co-planrity of the platform mercury cups were attached near the platform and a seperate Plate having Digital Electronic Micrometer stage with Conical Tip was used to touch the top level of mercury in the cup and electric bulb was used to signal ( indiacte ) that Micrometer tp touched the mercury.

Deviations at four places on micrometer was the height diff in the platform top for which co planarity was to be checked.

Repeatablity was observed within 0.008 mm. which was fairly satiusfactory .

Udayan

Thanks Udayan , that was very interesting and helpful. 0.008 mm accuracy sounds very good (though that depends on the application I suppose ). Kris

Mercury is now a banned substance in Europe and is being phased out where ever possible. Thermometers now can not used mercury. I suspect any portable device would now be a controlled item, requiring a special license to use it.

Hi !!

Thanks for this valuable information. Mercury in the conventional thermometer for measuring human body temprature may be harmful thats why probably it is being phased out.

However for other engineering applications like level or other such application does not have hazards so it may still find it's application. By any chance may readers on this blog be informed the releavant clauses banning this material " Mercury " ?

Can any one suggest other alternatives ? I am sure we enginners and technologists would always be on look out for new ways and solutions and challange the status quo

Udayan