Jan Warren of Brighton, Michigan, asks:

“I have a 1982 Catalina 30 and have just purchased a 4:1 boom vang. What is the best way to attach the vang to the boom and mast? I have been told to do it different ways and am a little confused. The vang is set up with a snap shackle for the mast attachment. I was thinking of installing a Forespar curved base mast eye and drilling and tapping the screwholes for it. For the boom I was thinking of a bail, but I’m not sure if screws will be strong enough or whether I should through-bolt it.”

Win Fowler replies:

I recommend you use bails for both ends, mounted on bolts running entirely through each spar. Bails similar to those in Schaefer series 90.09–90.12 or Ronstan series RF1045 –RF1048 should work well. In this application the attachment bolts will carry mostly shear loads. The loads on each end of the vang will be the same, so it’s probably wise to treat them similarly. The Forespar fitting you mention is, I believe, designed for use with a whisker pole. It is intended to carry mostly a compression load in the plane of the ring and would not be happy in the role you contemplate for it.