What plumb-bob sizes are available?
|Although plumb-bobs come in many shapes and sizes, they are typically categorised by their weight. Ounces are still the preferred unit of measurement for plumb-bobs though many manufacturers will state the relative metric equivalent.|
|Some plumb-bobs are very light and weigh only an ounce (28g) or less. These kinds of plumb-bobs are typically used in delicate scientific instruments or as novelties such as necklaces or watch fobs.|
|At the other end of the scale, there are some plumb bobs used by bridge builders and in mine surveys that are very heavy and can weigh up to 200 pounds (90kg).|
|For most domestic or on site purposes, plumb-bobs weighing between 4oz – 1lb (115-450gm) will be suitable.
As a general rule, the longer the required length of string is, the heavier your plumb-bob should be. It’s hard to suggest an exact weight based on a certain string length due to the varying shapes of plumb-bobs and types of string, so it is more a case of trial and error here.
|It is worth noting here that if you are working outdoors, then a heavier plumb-bob is advantageous as it will be less likely to be corrupted by wind.|