Ask Sail: Boom Raising
Dan Smith of Port Wing, Wisconsin asks:
I have a 30-foot C&C. The boom on this boat is too low for a standard vang; instead it has to be rigged to the toerail. The mast has a female internal track that receives round slugs. I’ve lived with the rig, but it is growing old. Can I raise up the boom with this type of mast track to make room for a vang?
Win Fowler replies:
I don’t remember the exact configuration of the C&C 30 gooseneck attachment, but it is likely held in place by rivets or machine screws. Provided you can remove these, you should be able to reposition the attachment and drill and tap new machine screws to hold it in place. You should fill the old holes with short machine screws to be sure there is sufficient support for the compression load on that part of the mast, which will increase with the new vang. Depending on how high you raise the boom, you may also need to raise the gate for feeding in the luff slides. And, of course, you’ll need to have the mainsail shortened, taking care to preserve the thread line from head to clew.
I’d be more concerned about where the new vang attaches to the mast (or possibly the mast collar at the deck). This attachment will typically be under more load than the gooseneck, and the load will be up and aft. If attached to the mast, the vang fitting should extend around the mast far enough that its fasteners are loaded mostly in shear. The vang fitting on the boom should provide a good example. If the vang leads to the mast collar, this should be fixed to the mast so that the load does not lift the deck.