From E. W. Marshall, P.E.:
Quickly calculate the proper length bolt for A325 or A490 structural bolt connections. Simply select your bolt diameter, desired washer type, and input your ply thicknesses. The correct bolt length, using industry standards recommendations, is shown immediately. 'Threads in shear plane' condition is determined as well as the calculated stick-thru past the installed nut.
--- Rapid slider-enabled ply thickness input.
--- Provides 'threads in shear plane' condition.
--- Load indicator washer option available.
--- Conforms to the accepted practice for structural bolt length determination.
--- 1/2" thru 1" diameter bolt capability.