Originally Posted by diegodog
The trusses are perfectly level if I place the level down the length of the truss.
the level perpendicular to the trusses
go from high to low back to high across the trusses as I move the level down the 60 ft span.
Since they are level the long way, to make them all equal height you'd need two identical thickness shims at each end of each truss.
Elevate the two end ones first.
And decide what is "close enough" to a planar, flat and level surface over these distances. 1/8"?
You might want to use 3, 5 or 7 string lines because you are leveling a two-dimensional surface.
Your leveling tools should be at least 5x better than the desired end result. Some of Grainger's levels are advertised as high accuracy and the catalog gives specs. A liquid level/garden hose is probably good to +/- 1/16" over whatever distance you want.