Wednesday, November 11, 2015

Mast Raising Considerations

Previously, I mentioned a couple of issues re the King Plank, the mast step, supporting the mast step and stepping the mast. I spent a bit of time (away from sanding) trying to sort out just what those issues are for me. So, here they are:

King Plank: Pretty straight forward - follow the plans. Except, I have concerns about the position of the mast step. More on the King Plank later.

Mast Step: John drew up a balance lug yawl sail plan based on the 100sf Scamp sail (I want to use my 105sf GIS sail). The mast step is positioned right aft of BH-1. With the mast in place, access to the bow compartment is not possible. I wonder how often I'll need to access that space when the mast is stepped. Fortunately, John did not include a mast box for this sail plan (otherwise access to the bow space would be impossible).

Supporting the Mast: The plans show the step at BH-1 and a hole through the deck and King Plank (creating the partners). (Think of Wile E. Coyote's black holes. The clamps are holding mock support pieces.)



This arrangement supports the mast at the partners but it means holding the mast vertical, lifting it almost 24" to clear BH-2 and reaching about 34" from BH-2 to the partners to place the mast through the partners. Now, my birdsmouth mast is respectably light at 24 lbs but I don't want to be balancing it vertically while leaning forward to reach the partners. I want a different way to step the mast.

What I want is a way to put the foot of the mast in the step and walk the mast to vertical. This would, I thought, mean creating a slot in the King Plank and cutting BH-2 to accommodate the slot. I thought the King Plank and BH-2 could be adequately supported to accomplish this - but I was - and am - hesitant to cut any of the bulkheads.

What I came up with is to cut a slot in the King Plank between BH-1 and BH-2, beginning at the mast location and ending several inches forward of BH-2.



I still think the King Plank will need additional support/structure, perhaps something as simple as a 1x doubler between the two bulkheads. A plug to fill the slot will support the mast.

Raising the Mast: Standing in the boat and holding the mast horizontally, the mast is already above the top of BH-2, which makes slanting the foot of the mast forward and down into the slot and into the step much easier than balancing the mast vertically. Once the mast foot is in the step, walking the mast to vertical and securing the mast with the plug should be straight forward.

I'm still fiddling with details but I think the concept is feasible and doable

2 comments:

  1. That looks a very good solution to the task of raising the mast safely. An added benefit is being able to adjust to mast position back a bit should the helm balance need some tweaking.

    ReplyDelete
    Replies
    1. Thanks Denis. You are right, I will be able to tweak the mast if need be,

      Delete