Hand level
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A hand level is a simple tool used for rough leveling and estimating elevations. It consists of a telescope with crosshairs and a spirit level. To use it, the user holds it at eye level and adjusts it until the spirit level bubble is bisected by the crosshairs. Readings are then taken from a staff to determine elevations or differences in elevation between points. While less accurate than other instruments, it is cheap, portable, and easy to use, making it suitable for small-scale construction layout and preliminary elevation work.
Hand level
- 1. Hand Level By : Durgesh Kumar Yadav
- 2. Definition • A hand level is a tool used for rough levelling i.e. estimation not precision.
- 3. Construction It mainly consists of :- A telescope ( 10 to 15cm long). Spirit level. Eye piece. Object lense. Reflecting mirror having half width of the instrument. Cross wire. Focusing screw.
- 4. How to Use the Hand Level Steps :- 1. Hold the instrument in hand at the eye level. 2. Raise/ lower object end till the image of bubble seen in the reflecting mirror is bisected by cross wire. 3. Take the staff readings against cross wire.
- 5. How to Use the Hand Level
- 6. Adjustment of Hand Level
- 7. Setting & Levelling of HAND LEVEL • Bubble of spirit level should be at center. • Instrument & line of sight should be horizontal. • For greater stability : Use of “forked bush pole”
- 8. Uses of Hand level • Mainly it is used for rough levelling in small scale work but it can be used for : 1. Setting out contour lines. 2. Measuring difference in elevation b/w two points.
- 9. Setting out Contour Lines Fig. Determination of Height of the level
- 10. Setting out Contour Lines
- 11. Setting out Contour Lines
- 12. Measuring Difference in Elevation • Measuring difference in elevation b/w two close points.
- 13. Measuring Difference in Elevation • Measuring the difference in elevation b/w two distant points.
- 14. Measuring Difference in Elevation • Formula : • Difference in elevation b/w A & B = sum of back sight readings – sum of fore sight readings • If +ve then A<B • If –ve then A>B
- 15. Advantages of Hand Level • Cheap as compared to other levelling instruments. • Portable. • Less time taking. • Easy operation.
- 16. Disadvantages of Hand Level • Less accurate as compared to other levelling instruments. • Suitable for only small scale work.
- 17. Thank You !