Seems easy, right?

 I mean, how hard could it be to keep rain water from running down the mast and into the cabin?  You make a mast boot, and seal it to the mast - probably using one of those jumbo-sized hose clamps as the final measure.  No leaks, right?

(BTW, being able to take this picture with the huge range of brightness between the sun-drenched mast outside and the shadowed mast inside is provided by a function called 'High Dynamic Range', part of the free - or was it 99¢? - iPhone app 'Top Camera' - I recommend the app for this capability as well as many others.)

Well, no. Despite all the measures, a recent rain revealed that I still have work to do here.

The picture is a little vague, but if you squint, you'll see those brown marks that show where water has snuck past the seal somewhere and run down the mast.  The brown stain is coloration leached from the teak wedges which hold the mast in position at the partners.

So I disassembled the seal I had built before.  Here's what I found:

• First, the silicone tape, tho it had bonded very well with the hose clamp, had not bonded well to the mast
• Next, because of the poor seal of the silicone tape, the long duration 3M tape underneath had turned to water-saturated mush.

After removing both, I applied a wrap of adhesive-backed aluminum foil (sold for sealing duct work) over the joint between the boot and the mast.  The thinking here is that the aluminum tape will not turn into mush on contact with water.

Finally, I re-applied the silicone tape, because it looks better.  (I hope I don't regret the decision to do this.  I am concerned about the paint bubbling up where moisture was trapped.  We'll see.)

Seems easy, right?