Boom attachment: Slotted groove?

[pbmaise]

I am making a boom from a wooden round mast. It holds my loose footed Gunter sail, and supports the sail when not in use.

The boom will have a stainless steel collar and 1.5" solid stainless steel pin.

My plan is to have the 1.5" pin extend from the boom into the gooseneck area of the mast.

In the gooseneck there is a 7/16" bolt.

Anticipated problem: If I simply drill a round hole in the 1.5" pin, the aft end of the boom will not be able to rise or fall without bending/breaking the 7/16" bolt.

Contemplated solution: Have machine shop make a notch in the 1.5" rod so there is available play.

Question: Okay? How long should notch be?

[pbmaise]

Here is a link to how Selden solved this problem.

Selden Extended Boom Bracket for Cumulus and Kappa (508-808-01) | P&B

They create a second pivot point along the bolt that goes into the gooseneck. This approach limits the vertical play of the pin along the bolt.

I will have to use a spring above and below the 1.5" rod to prevent the rod from striking the top and bottom of the goose neck.