Had the same problem with my Nacra 5.8na....the pin was too long, and when the mast was rotated, it was hooking on a cam cleat mounted on the beam next to the ball. Check and make sure that when you rotate the pin, or even the split ring is not hooking on anything...that should do it...





In fact that same thing almost occured with my I-20...and the pressusre stripped the ball....lucky for me my wife used her head (literaly) to catch the mast!