Mizzen Rain Hood

Because our mizzenmast is stepped inside the cockpit, the cockpit enclosure must by necessity allow for the penetration of the mast.  In an attempt to minimize the amount of rainwater that enters the cockpit via the mast, the enclosure has a "sock" that goes up the mast a little ways and is tied around it.  Undoubtedly it stops most rain drainage, but a still significant amount gets into the cockpit, annoyingly to wet our trousers when we sit down.

An improved solution was called for.

The problem, in the rain, no less.

My first attempt was a simple, straight strip of vinyl cloth, mightily stretched around the cross section of the mast.  For obvious reasons, tho I was able to make it work, it failed to meet my aesthetics criteria.  (That is aluminum tape - I have extolled it's virtues before...)

First attempt: sloppy

The first reason a straight strip of vinyl failed to conform easily is that the mizzen mast is not a round cross section.  And the second is that the bottom of the strip had to accommodate a larger diameter than the top, due to the presence of the top seam of the sock.

Mizzenmast cross section

Well, this obviously called for the application of the lesson learned in Making a Mast Boot, with a minor modification.

First, we need to have a tapered hood, smaller at the top than at the bottom in order to accommodate the sock. I decided that tho the sock was about 1/4" thick (1/2", counting both sides), I should make the hood slightly larger so that the sock could easily fit up inside the hood, and to accommodate the place where the ends of the sock overlapped. I chose to make the bottom of the hood 3/8" larger on a side, or 3/4", counting both sides.  So, the tapered section needed to have a diameter of 3.75" at the top, and 4.5" at the bottom.

Next, the mast cross section is not round. Instead, I chose to view it as two half-round sections, joined by two straight sections.

Since I already screwed up one piece of vinyl, I decided to make a paper pattern this time, using freezer paper (eh, it was what we had...). Using the instructions in the mast boot post, I traced out an arc of sufficient length to supply pieces for both the front and rear of the mast. The arc for the rear of the mast I made extra long so that the ends would be able to overlap, and then I cut this piece in two. Then I cut out a couple of straight sections to accommodate the sides of the mast.

When joined together, the pieces looked like this:

From left to right, this is:

• Rear piece, extra long
• Side piece
• Front piece
• Side piece
• Rear piece, extra long

The change in shape seems kind of subtle, but the paper pattern fit the mast perfectly when I tested it.

Taped to back of the vinyl

After testing the pattern, I taped it to the back side of the vinyl, traced its outline and cut it out:

Taa Daa!

And... DONE!

And now because the hood is tapered, if I need to remove the sock I will not need to disturb the hood because I will be able to slide the sock up under the hood when reinstalling it.

Mizzen Rain Hood