Related Manuals for David White L6-20N
Summary of Contents for David White L6-20N
- Page 1 L6-20N Level and LT6-900N Level-Transit L6-20N Level (Model 44-8824) LT6-900N Level-Transit (Model 44-8834) For customer service, call (815) 432-9200...
- Page 2 It is the customer’s responsibility to check and to ensure instruments are adjusted prior to using. David White is not responsible for errors caused by instruments that are out of adjustment. Contact your distributor, dealer or David White for information on the nearest facility to check if your instrument is properly adjusted.
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Page 3: Specifications
Specifications Meridian L6-20N Level Meridian LT6-900N Level-Transit Optimum sighting range: Recommended job range up to 200 feet. Accuracy range: Recommended for jobs requiring accuracy within 1/4" at 75 feet. TELESCOPE Power Length 10.5" (26.5cm) Minimum Focus 4 ft. (1.2m) Aperture .75"... - Page 4 General Description Meridian L6-20N Level Meridian LT6-900N Level-Transit 1. Telescope objective lens 9. Telescope lock lever 2. Eyepiece 10. Vertical arc 3. Focusing knobs 11. Vertical arc pointer 4. Instrument level vial 12. Vertical clamp 5. Horizontal graduated circle 13. Vertical tangent 6.
- Page 5 The vertical clamp must be hand tightened before the tangent will function. Both the L6-20N and LT6-900N have three leveling screws (14) for level- ing the instrument. The instrument is mounted to the tripod by screwing the tripod stud into the 5/8 x 11 JIS threaded base (15).
- Page 6 For easiest setup and best leg. operating results, it is recommend- ed that the David White tripod is used. It is important that the tripod is set up firmly. Make sure that the tripod points are well into the ground.
- Page 7 2. Before setting up your instrument, loosen the clamps. If using the level-transit, be sure the telescope lock lever is in the closed position. Attach the instrument to the tripod securely, hand tight- ening the tripod mounting stud to the instrument base. If setting up over an exact point, read step 3;...
- Page 8 #1, turn the instrument and observe the vial in position #2. Now center the bubble in position #2 using only screw Your David White Instrument VIAL POSITION should now be leveled up, but to be certain, double- check.
- Page 9 BUBBLE ADJUSTMENTS If the telescope bubble does not remain centered after having lev- eled the instrument, and reversed the telescope end for end (180°) (as described under the chapters entitled “Leveling the...Instrument”) the need for adjustment is indicated. Use a screwdriver.
- Page 10 Reading the circle and vernier The 360° horizontal circle is divided in quadrants (0-90°). The circle is marked by degrees and numbered every 10 degrees. To obtain degree readings, it is only necessary to read the exact degree at the intersection of the zero index mark on the vernier and the degree mark on the circle (or on the vertical arc of the level-transit.) 75 degrees...
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Page 11: Care And Handling
When sighting through the telescope, keep both eyes open. You will find that this eliminates squinting and will not tire your eyes. Remember to avoid touching the tripod while sighting. Removing the instrument from the tripod Loosen two adjacent leveling screws and unscrew the tripod mounting stud while holding onto the instrument. - Page 12 Using your instrument Levels and level-transits, as do all sighting instruments, operate on the principle that any point along a level line of sight is exactly level with any point along that line. Levels and level-transits The following jobs can be accurately performed with a level or level-transit used in the level position (with closed lock lever): grading for swimming pools, driveways, sidewalks, lawns, gar- dens;...
- Page 13 Running straight lines with a level Set up the instrument over Point A. A plumb bob should be held over Point B. Sight approximately on the plumb bob cord and turn the telescope so that the vertical cross hair coincides with it. To align the intermediate points, direct the person with the leveling rod to the right or left until the rod coincides with the vertical cross hair.
- Page 14 Measuring and laying out angles For measuring angles, attach a plumb bob cord to the hook on the screwdriver-style handle of the tripod. The point of the plumb bob will then indicate a point on the ground directly below the center of the instrument and, therefore, will also indicate the center of all angles to be measured.
- Page 15 Swing the telescope to the desired angle and move the rod to intersect the vertical cross hairs. This establishes your angle. NOTE: The L6-20N and LT6-900N have horizontal verniers which read to 15 minutes (1/4 degree). For projects which need more accurate angle measurement for layout, we recommend using a more precise instrument with a 5 minute vernier.
- Page 16 Using your instrument Level-transits The following example illustrates how to use a level-transit for laying out roads, building lines, ditches, orchards, fences, hedges, fields, etc. Running straight lines with a level-transit (Although it is possible to run straight lines with a level, it is faster and more accurate to use a level-transit.) To run a straight line between stakes A and E, position the instru- ment directly over A.
- Page 17 Only trained technicians should service this instrument. Instrument service and repair Your David White instrument is a precision-made optical instru- ment and like all good precision tools requires reasonable care and careful handling. It is recommended that all instruments be serviced by a reliable instrument repair station at least once a year to insure accuracy and reliable performance.
- Page 18 David White service facility. If you have questions about checking for calibration, contact David White or a repair facility. All actual adjusting of the instrument must be done by a qualified service facility.
- Page 19 For your records Model No. • L6-20N • LT6-900N Date purchased Serial No. For owner identification, please complete and mail the attached registration card.
- Page 20 Buyer. 3. The foregoing warranty does not apply to David White instruments damaged in transit to or from David White or a David White authorized service center. THE FOREGOING WARRANTIES ARE EXCLUSIVE AND IN LIEU OF ALL OTHER...