A practical mast boot


When Tom and I set up our Peterson 44, Oddly Enough, for voyaging, the mast had been out of the boat for three years. The mast on a Peterson 44 is keel stepped and I couldn’t recall what kind of boot had been installed to keep water from running through the deck and into the cabin. I wandered around the yard in Florida where we were hauled, and found a man putting the finishing touches on his own mast.

“Truck inner tube,” he said. “Hasn’t failed me yet.”

Most truck tire repair businesses will give away blown inner tubes, even in the bigger towns in the islands. The original boot lasted 10 years, and gave watertight protection until the Sunbrella covering lost its UV protection. I recently made a new one, using part of an inner tube I had on the boat.

Here’s how to make the boot:

1) Cut crosswise through the tube and wrap around the base of your mast to get a rough idea of the fit. Add plenty of extra length for overlapping edges and errors in calculating; measure along the tube and make another cut.

2) Using a flexible measuring tape, measure from deck level (outside the ring of your mast collar) a comfortable distance up the mast above your mast wedges. This will be the height of your boot. Be generous in measuring, and then add 3 inches. Total measurement will likely be 8-9 inches.

3) You should now have a semicircular piece of tube. Slit this piece along the outside circumference and open it up. Measuring from the outer circumference of one side of your opened tube, cut the rubber so that you have a curved strip whose width is the dimension determined in step two, and whose length is the circumference of your mast collar on the outside and the circumference of your mast on the inside, with room for overlap in both cases (an extra 4 inches is advisable).

4) To set up the mast boot you will need two hose clamps, one to go around the mast and one around the collar. I put two clamps together to make one big enough for my collar. You will also need a tube of sealant and a screw driver to tighten up the hose clamps, plus paper towels or rags to clean up pesky sealant drips.

5) Position the rubber boot around the mast with the wider bottom above the narrower top (upside down). Pull edges together and secure the first hose clamp over the rubber. Tighten lightly. Don’t worry if it feels awkward; with the clamp loosely in place you can pull on the rubber without losing it.

6) Roll the boot over the clamp and pull it down over the collar. You should be able to use the natural curve of the inner tube to get a pretty good fit over both the mast and the collar, though a few puckers at the bottom are okay. Here is where you will see if you left enough room for a good overlap. Roll the boot back up, and by pulling on the corners with it unrolled you can get a smooth fit. It may take a few tries.

7) When you’re satisfied, tighten the clamp so the rubber mushes up, but doesn’t flatten. Roll the boot down. Fasten your second clamp loosely around the mast and pull it down over the collar, making sure the rubber stays in place. Make sure the overlapped edges are flat against each other. If you’re not happy with the fit, pull the boot up and work at the top corners again.

8) With the bottom hose clamp again out of the way, spread sealant around the outside of the mast collar and under the overlapping edge. Smooth boot in place. Work the hose clamp over the collar once again and tighten gradually.

Run a bead of sealant in the joint where the rolled-over boot meets the mast. Mast boot is now finished.

Rubber will degrade in sunlight, so it is imperative to cover the boot for both looks and protection.

By Ocean Navigator