Innertube size for mast boot

[driftless]

While the mast is down I'd like to put on an innertube mast boot. I tried a leaky tractor tube that I had on hand. It seemed a likely candidate when I draped it deflated over the mast, but it ended up being too big. I'm wondering if anyone knows what size tube has worked well for them? The mast circumference on my 38 is listed as 21 and 7/8 inches. I can't find anywhere that lists girth of a deflated tube. I'd like to avoid buying and cutting up a bunch of tubes to find the right fit.

 

[goldenstate]

MAST BOOT UNIVERSAL

Universal Mast Boot. Made of extremely flexible UV resistant vinyl. Designed to fit a number of sizes of mast and deck collars of the same basic shape. Molded in small steps so top and bottom can be cut at the level that provides a snug fit to the mast and the deck collar. Boot may be installed...

shop.hamiltonmarine.com

 

[Ralph Hewitt]

I have read some where to use a toilet bowl WAX RING push down around it (mast & deck) then tape.
Any reviews on that method?

 

[Loren Beach]

I have read some where to use a toilet bowl WAX RING push down around it (mast & deck) then tape.
Any reviews on that method?

No in-use review , but that wax will compress and ooze out over time. It has no structural integrity.

I would go with Tom's solution.

 

[Ralph Hewitt]

No in-use review , but that wax will compress and ooze out over time. It has no structural integrity.

I would go with Tom's solution.

Sometimes I wish for a west marine type store...
Import transport, tax & duty right now is about the cost of the product.

 

[Rocinante33]

Tyler and Ralph,

I used the commercial product but there is no reason why you can't cut a large inner tube to size and use it. The top and bottom edges will be crescent shaped, each about 3" longer than the circumference of A) top side, mast, B) bottom side deck collar.

Start by making a pattern with an old piece of cloth. You can do it!

 

[driftless]

Tyler and Ralph,

I used the commercial product but there is no reason why you can't cut a large inner tube to size and use it. The top and bottom edges will be crescent shaped, each about 3" longer than the circumference of A) top side, mast, B) bottom side deck collar.

Start by making a pattern with an old piece of cloth. You can do it!

I've got the mast unstepped right now, so I'm hoping to not have a seam in the tube. Hence the search for the right size - just snug to the mast with enough stretch to fit over the collar.
If I can't find the right size before the mast goes up I'll do what you suggest and get to work with the vulcanizing glue.
I'll need a fabric cover over the rubber boot so tracing a pattern is a good place to start either way.
Thanks Keith.

 

[Loren Beach]

I've got the mast unstepped right now, so I'm hoping to not have a seam in the tube. Hence the search for the right size - just snug to the mast with enough stretch to fit over the collar.
If I can't find the right size before the mast goes up I'll do what you suggest and get to work with the vulcanizing glue.
I'll need a fabric cover over the rubber boot so tracing a pattern is a good place to start either way.
Thanks Keith.

We just stepped our Kenyon spar, and I believe that Fisheries was the source for this. I do not know the model, so you would have to measure the mast diameter and probably also the diameter of the SS base.
Mast and cabin top "base" are probably just like ours, would be my surmise.

Universal Mast Boots - Sailing Specialities | Fisheries Supply

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We also have a "Sunbrella" cover to protect ours from UV.

 

[Grizz]

Tangentially related with a bit of directly related (?!): not sure which size was selected, but the Fisheries Universal (cut down to size) worked fine in 2019 and hoping it'll repeat in 2021.

The OEM 'hard mast boot' sits on a shelf, waiting to be photographed, mapped and plugged into a 3-D printer to build a replacement with a material TBD. No clue if that's even possible, but it's worth a try. UV degradation isn't a concern (5 month season, mast un-stepped and stored inside) and if it works and lasts 2-3 seasons, it'll be worth the effort. "if it works..."

This concludes this tangent...

 

[markvone]

I've never done this but here's the math.

Mast circumference (C)= 21.825" C=3.14x Diameter D= 6.966

So a 6 or 7 inch wheel size tube. Probably a 6 inch stretched over the mast. 6 x 3" wide?

Remember you'll have a valve on the interior (mast side) of the tube to deal with.

Mark