![]() Even today, they are the basic tool for determining verticality with respect to gravity, used to place an instrument over an exact point in space to accurately set markers. This plumb line is important for lining up anatomical geometries and visualizing the subject's center of balance. A plumb bob (sometimes referred to as a plummet) is one of the oldest, most fundamental tools in surveying work, dating back to the ancient Egyptians. A plumb bob, plumb bob level, or plummet, is a weight, usually with a pointed tip on the bottom, suspended from a string and used as a vertical reference. The device used may be purpose-made plumb lines, or simply makeshift devices made from a piece of string and a weighted object, such as a metal washer. We carry a variety of high quality plumb bobs and reels from top manufacturers. Students of figure drawing will also make use of a plumb line to find the vertical axis through the center of gravity of their subject and lay it down on paper as a point of reference. Ī plumb bob may be in a container of water (when conditions are above freezing temperatures), molasses, very viscous oils or other liquids to dampen any swinging movement, functioning as a shock absorber.ĭetermining center of gravity of an irregular shape The early skyscrapers used heavy plumb bobs, hung on wire in their elevator shafts. A wide variety of shapes have been used for plumb bobs, but plumb bobs are generally torpedo shaped with a point on one end and a hole through which the cord. Sokkia Plumb Bob Cord is braided cord and comes in a 50 yd spool in fluorescent red (812440), fluorescent yellow (812439), orange (812423), or white (812413). Step 4: Reinstate the lid on the plumb bob’s heavy end. ![]() Pull the remaining string through the plumb bob top to tuck the knot within the cap you can remove. The rear tapeman reads the graduation marked by his plumb bob cord and announces the measurement of the partial tape length to the nearest 0.01 meter. Step 3: Make a dual knot at the string’s end. Gammon Reel Refill Cord - Orange -Gammon Reels & Plumb Bobs- eGPS Solutions Inc. The line should be at least as tall as the distance between the floor and the ceiling, usually 8 feet. A variation of this tool has the plumb line hung from the top of an inverted T shape. Shop our gammon reels and plumb bobs for your next surveying or. Plumb Bob Setter Magnetic Plumb-Rite Auto Recoiling Cord Quick-Stabilizing Hanging Wire Hammer Hand Tool with 3/6/4.5/8M 1. An A-frame level with a plumb line hung from the vertex was also used to find horizontal these were used in Europe until the mid–19th century. However, if they are mounted on a suitable scale the instrument may also be used as an inclinometer to measure angles to the vertical.Īncient Egyptians used a plumb line attached to the top outer part of a tool resembling a letter E when placed against a wall, the plumb line would indicate a vertical line. A plumb bob and line alone can determine only a vertical reference.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |