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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. After you level the instrument, release the
lock that holds the telescope in the level position and swing the
instrument until point E is aligned with the vertical cross hair.
Tighten the horizontal clamp so the telescope can move only in a
vertical plane. By pointing the telescope up or down, points B, C
and D can be located.

Establishing vertical lines and planes

It is necessary to use a level-transit instrument for taking vertical
sights, such as lining up a building wall, aligning piers or fencing,
flagpoles, T.V. antennas, plumbing windows or doorways, etc.
To establish vertical lines and planes, first level the instrument,
then release the locking levers which hold the telescope in the
level position. Swing the telescope vertically and horizontally until
the line to be established is directly on the vertical cross hair. If the
telescope is rotated up or down, each point cut by the vertical
cross hair should be in a vertical plane with the starting point.

A

B

C

D

E

15

Summary of Contents for L6-20N

Page 1: ...0 5 0 4 0 30 20 10 50 5 0 30 3 40 4 4 50 5 50 50 10 20 30 40 50 6 0 7 0 8 0 90 80 70 6 0 5 0 5 0 4 0 4 0 3 03 0 2 02 0 10 10 20 20 30 30 4 04 0 5 05 0 6 0 6 0 7 0 8 0 90 80 70 6 0 5 0 4 0 30 20 10 L6 20N Level Model 44 8824 LT6 900N Level Transit Model 44 8834 For customer service call 815 432 9200 L6 20N LT6 900N Owner s Guide 00 8830 810 ...

Page 2: ...acy Quality and innovation since 1900 All instruments are adjusted when they are shipped from the factory 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 ...

Page 3: ...re 75 19mm Field of View 2 100 6m 30m No of Lenses 6 HORIZONTAL CIRCLE Graduation Diameter 3 62 92mm Graduations Each 1 Numbers Each 10 0 90 0 Vernier Double direct to 15 min VERTICAL ARC LT6 900N only Graduations Each 1 Numbers Each 10 45 0 45 CENTER Planar bearing LEVEL VIAL 10 min per 2mm WEIGHT L6 20N LT6 900N Instrument only 3 25 lbs 1 5kg 4 5 lbs 2 0kg Instrument case 3 oz plumb bob 6 lbs 6 ...

Page 4: ... 30 4 04 0 5 05 0 6 0 6 0 7 0 8 0 90 80 70 6 0 5 0 4 0 30 20 10 50 5 0 30 3 40 4 4 50 5 50 50 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 Horizontal vernier 14 Three leveling screws 7 Horizontal clamp 15 5 8 x 11 JIS threaded base 8...

Page 5: ... of 1 4 15 minutes See page 9 for circle and vernier reading instructions Approximate horizontal sightings are held firmly in place by means of a clamp 7 Then precise horizontal settings can be made with the tangent 8 The clamp must be hand tightened in order for the tangent to function THE FOLLOWING INDENTED PARAGRAPHS APPLY TO THE LT6 900N LEVEL TRANSIT ONLY The Meridian Level Transit is a combi...

Page 6: ...ipping the con crete attaching chains between the legs or putting a brick in front of each leg If setting up in dirt apply your full weight to each leg to pre vent settlement Check the tripod legs They should have about a 3 foot spread posi tioned so the top of the tripod head appears level If using a tripod with adjustable legs be sure the leg levers are securely tight ened 10 6 0 7 0 80 90 80 70...

Page 7: ...ob attach cord to the plumb bob hook on the screwdriver style handle of the tripod Knot the cord as illustrated Move the tripod and instrument over the approximate point Be sure the tripod is set up firmly again as described in step 1 Shift the instrument on the tripod head until the plumb bob is directly over the point Then set the instrument leveling screws as described in step 4 Hanging the plu...

Page 8: ...ame direc tion as your left thumb Do not permit the screws to come com pletely out of their bushings Keep about half the length engaged When the bubble is centered in position 1 turn the instrument and observe the vial in position 2 Now center the bubble in position 2 using only screw C Your David White Instrument should now be leveled up but to be certain double check Rotate the instrument 180 so...

Page 9: ...ting screw A facing to the right of the bubble and with telescope directly in line with two of the three leveling screws note to which side the bubble is off If to the left loosen screw B very slightly to remove ONE HALF the error Remove the other half of the error with the two level screws in line with the tele scope If the bubble is still not exactly centered repeat the proce dure If bubble is o...

Page 10: ...actions or minutes There are 60 minutes in a degree If the vernier zero does not coincide exactly with a degree mark on the circle note the last degree mark passed and reading up the vernier scale locate a vernier mark that coincides with a circle mark This will indicate your reading in degrees and minutes Sighting and focusing the telescope Aim the telescope at the object and sight first along th...

Page 11: ...a soft non abrasive cloth and mild detergent Never use solvents or submerge the instrument in water Do not attempt disassembly 2 If the instrument is wet dry it before you return it to its case 3 When the instrument is not being used keep it in its carrying case 4 When moving the instrument over a long distance by foot or by vehicle remove it from the tripod and place it in its protective case 5 W...

Page 12: ...ls and foundations establishing drainage for landscaping aligning trees and shrubs and building terraces and stone walls Determining differences in elevation One of the main uses of levels is for measuring the differences in elevation for grading With the instrument leveled we know that since the line of sight is perfectly straight any point on that line of sight will be exactly level with any oth...

Page 13: ...ly A sighting rod should be held at the begin ning contour line about 100 feet from the instrument Sight the rod and set a target on the rod at the point where the horizontal cross hair intersects the rod Then move the rod to approximately the next place where a contour line stake is to be set and move the rod up or down the slope until the line of sight through the tele scope again intersects the...

Page 14: ... that the vertical cross hair is directly in the center of the rod at station 2 Set the horizontal circle at zero to coincide with the vernier zero Then turn the telescope to sight on station 4 and read the angle In this case it would be 120 degrees Move the instrument and tripod to station 2 and level exactly as before When the instrument has been leveled sight back to read on station 1 Set the h...

Page 15: ...rument directly over point C and line up the cross hairs on B Set horizontal circle to zero Turn the telescope 90 degrees to the right The vertical cross hair of the instrument will now cut across point E and point G Measure the distance from the lot line to the corner of the pool which is C E Also the distance E G is measured along this line Place a stake at points C E and G Next set up and level...

Page 16: ... Tighten the horizontal clamp so the telescope can move only in a vertical plane By pointing the telescope up or down points B C and D can be located Establishing vertical lines and planes It is necessary to use a level transit instrument for taking vertical sights such as lining up a building wall aligning piers or fencing flagpoles T V antennas plumbing windows or doorways etc To establish verti...

Page 17: ...e 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 If the instrument has been dropped or severely jarred the instru ment s line of sight may be affected The line of sight must be exactly perpendicular to the vertical axis of the instrument This is checked by the two peg a...

Page 18: ...led sight on the wall that is 10 feet away 5 Place a two foot section of rod ribbon on the wall so the horizontal cross hair of the instrument intersects the middle of the two foot section 6 Rotate the instrument 90 and sight on the wall that is about 75 feet to 100 feet away 7 Place a two foot section of rod ribbon on that far wall so the horizontal cross hair of the instrument intersects the mid...

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: ...ES WHATSOEVER Limitations and Exclusions 1 The foregoing warranty does not apply to David White instruments subjected to negligence accident improper operation or maintenance or storage instruments damaged by transit or circumstances beyond Seller s control instruments modified or damaged due to unauthorized repairs made by other than David White or authorized David White ser vice center personnel...

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