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CHAPTER 6 CARE AND ADJUSTMENT OF SURVEYING EQUIPMENTTo a great extent, the accuracy and quality of your surveys will depend upon how well you take care of your surveying equipment; therefore, the first part of this chapter reviews the proper instrument handling, stowing, and maintenance practices that you studied in the EA3 TRAMAN. While to some readers this review may seem redundant, taking care of your equipment properly cannot be overemphasized.In this chapter we also discuss instrument adjustment and repair. As used in this chapter, the term adjustment means bringing the various fixed parts of an instrument into proper relationship with one another. It is different from the ordinary operations of leveling the instrument, aligning the telescope, and so forth.CARE OF INSTRUMENTS As you know, every instrument is accompanied by a users manual that tells you not only the proper operation and components of the instrument but also its proper care and maintenance. Study this users manual thoroughly before you even attempt to use the instrument. Some suggestions for the care and maintenance of surveying equipment are discussed in the following paragraphs.HANDLING, CARRYING, AND STOWING Always exercise care in handling instruments, such as the transit, level, theodolite, or plane table. When removing an instrument from its carrying case, NEVER grasp the telescope. Wrenching the telescope in this manner could damage a number of delicate parts. When you set up an instrument, make sure that it is securely fastened to the tripod head. In tightening the various clamp screws, leveling screws, and adjustment screws, bring them only to a firm bearing. Overtightening these screws may strip the threads, twist off the screw, bend the connecting part, or place undue stresses in the instrument. NEVER leave an instrument unattended while it is set upon a street, near construction work or in any other place where it can be damaged. When you carry an instrument mounted on a tripod, place the instrument and tripod on one shoulder with the tripod legs pointing forward and held together by your hand and forearm. If you are walking along a sidehill, you should always carry the instrument on the downhill shoulder. This leaves the uphill arm and hand free to catch yourself should you trip or stumble. Before climbing over a fence, you should first place the instrument on the other side with the tripod legs well spread. Also, when carrying an instrument, you should ensure that all clamp screws are only lightly clamped so that the parts will move if the instrument is struck. Avoid carrying the instrument on your shoulder through doorways or beneath low-hanging branches; instead, you should carry it under your arm with the head of the instrument to the front.Every transit, theodolite, or level comes equipped with a carrying box or case. The instrument and its accessories can be stowed in the case in a manner that ensures a minimum of motion during transportation. The instrument should ALWAYS be stowed in the carrying case when it is not in use.Bags are provided for carrying stakes and hubs. These are usually canvas bags equipped with a shoulder strap and closely resemble a newsboys bag. A newsboys bag, in fact, makes an excellent carrying bag for stakes and hubs. So does a Navy seabag, equipped with a shoulder strap.Various types of leather or canvas bags and sheaths, such as chaining-pin quivers, plumb-bob sheaths, and sheaths for Abney and Locke levels, are provided for various items of equipment. Most of these can be attached to the belt. Leather pouches, also usually attachable to the belt, are available for carrying small tools, marking equipment, turning-point pins, and the like. In time you will learn various conveniences, such as carrying your supply of surveyors tacks stuck in a rubber ball or in a piece of softwood attached to your belt.CLEANING AND LUBRICATION All surveying instruments, equipment, or tools must be thoroughly cleaned immediately after you have used them; for example, after each use, you must dust off the transit or theodolite and wipe it dry before placing it back in its case. Remove all dust with a soft brush before wiping dirty components with a clean cloth. When the instrument becomes wet, you should remove it from its carrying case and dry it thoroughly at room temperature once you get home. NEVER leave a wet instrument stored in the carrying case.NEVER rub the lenses of a telescope with your fingers or with a rough cloth. Clean chamois leather or a lint-free soft cloth is suitable for this purpose. Occasionally, you may clean the lenses with a soft cloth that is dampened with a mixture of equal parts of water and alcohol.You should always remove mud and dirt from tripods, range poles, leveling rods, and so forth, immediately after each use. This is very important, especially when the surveying gear is made of a material that is susceptible to rust action or decay. When lubricating instruments, you must use the right lubricant that is recommended for the climatic condition in your area; for instance, it is recommended that graphite be used to lubricate the moving parts of a transit when the transit is to be used in sub-zero temperatures; however, in warmer climates you should use alight film of oil (preferably watch oil).Consult the manufacturers manual or your senior EA whenever you are in doubt before doing anything to an instrument |
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