As a construction millwright, I frequently need to establish very accurate plumb lines for machinery alignment in places where a transit is impractical. I rely on my 24-oz. brass plumb bob. When it’s not necessary for the end of the bob to be visible, I immerse it in a bucket of oil to reduce motion from vibration and wind.
To avoid the problem of winding and unwinding line, I replaced the string in an empty chalk box with 50-lb. test braided nylon fishing line and tied the bob to the end; it makes a convenient reel.
Dave Walter, Rossville, IL
