Centerboard pivot details

The centerboard pivot (M12) is attached to the centerboard box and the centerboard with bronze bearings (12x18x16 mm). It was pretty challenging to get the whole thing straight, but after mulling over, a proper approach was found. Since I do not own a column drill I used a drill guide (Kanzawa K-801).

Once the epoxy had cured around the bearings, it was time to remove the bolt. You needed some torque to make the bolt move as there was some epoxy on the top and bottom side of the hole. After that, it was easy to remove the bolt from the hole with a hammer.

The next phase was a tricky one. As the pivot pin hole in the centerboard trunk wasn’t straight-engouh, the straightness had to be accomplished with an alternative approach. I made the starboard side hole bigger that the pivot pin would be looser in it. We lowered the centerboard into its trunk and I put the pivot pin through the hole and centerboard. Then I stringed a 4 mm spacer line on the both sides of the centerboard at the fore and aft to make the centerboard stay equally far from the trunk inner walls. Space between the trunk and the centerboard was 3 mm on the both sides.

Gluing bearings into the centerboard trunk was a fairly straight-forward operation after you had forced the centerboard straight. The most challenging part of it was looking into the trunk and filleting the seams of the bearing. Fortunately we had a small telescope mirror which suited to the need perfectly.

It was a pretty messy task to glue the bearings but at least the hole through the centerboard and its trunk is straight. I have to say that straightness of the pivot pin holes was the most stressful part of the hull assembly.