CHAPTER 6 CARE AND ADJUSTMENT OF SURVEYING EQUIPMENT

CHAPTER 6 CARE AND ADJUSTMENT OF SURVEYING EQUIPMENT To 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 user’s manual that tells you not only the proper operation and components of the instrument but also its proper care and maintenance. Study this user’s 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 newsboy’s bag. A newsboy’s 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 surveyor’s 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 6-1