PocketShip.net

Hey! I am debating a detachable tabernacle or fixed in position. I'd prefer the fixed position option as it seems best from a strength perspective. But...if I do this the boat is about 3" to tall to exist the garage. Thoughts about reducing the height? Bad ideal or cunning plan?


IMG_1234.JPG

Although I have no answer, I'll be following this thread closely. I have the same issue regarding fitting my PS into the garage (as I suspect many do given a "standard" garage-door height). I'd prefer a permanently installed tabernacle also - stronger, less hassle to launch, supports the mast during transport, etc. I know JH has suggested construction details for a removable tabernacle - and I'm guessing that he'd have commented if shortening the structure was an option. But I'll be watching.

Good luck, and if you decide on a removable tabernacle, I'd appreciate construction details. I'm a ways from that step at the present.

All the best,
Mark Nunlist
Lebanon, NH

I can't comment on altering the tabernacle design. BUT, as regards the removable vs. anchored consideration: Make sure you are measuring with the boat on the trailer! Maybe I have a small garage or a tall trailer, but the tabernacle was way more than 3" too high. Also consider the height of the boom gallows (if you are using one), because that is pretty high as well.

I have a removable tabernacle with a reinforced plywood doubler in the cabin. After some trouble early on where my shrouds were not tightened sufficiently, I've had no issues since. You can read about removable tabernacle design in this thread: viewtopic.php?f=3&t=416

So, to summarize, I don't think theres any disadvantage to a removable tabernacle.

I'm planning to go with a removable tabernacle. It seems to me that whether it's glued on or bolted on the leverage on it from the mast would be about the same. What's more, if there is ever some damage, having it removable would make repair or replacement more easy, I would think. Maybe I'm missing something. I did reinforce the cabin roof/bulkhead joint with kevlar, unidirectional carbon cloth and many layers of fiberglass as well as making the deck cleat behind it more substantial than designed by making it thicker and of glued laminations so the grain follows the curve of the cabin top. I have a post with pics of it here on the forum somewhere. I think it's in the thread about the bulkhead failures due to mast torque.

Awesome responses team and informative. Would be great to hear from the boss! John?

PocketShip's tabernacle is one of my favorite features of the design. With practice, you can be sailing in less than 15 minutes after you get to the launch ramp. And that's almost entirely thanks to the tabernacle, which allows the boom to stay rigged. The tabernacle also holds the stowed mast in the perfect orientation to form a ridgepole for a tarp while the boat's in storage, a minor feature which can nevertheless double the life of a disused PocketShip.

On the other hand, the tabernacle is really tall! You need 104 inches - over 8-1/2 feet - of overhead clearance to store the boat indoors. Ditch the tabernacle (and the boom gallows) and you'll need only about 77" of overhead clearance.

The weight, windage, and construction time are all reduced if the tabernacle is deleted. As much as I like it, I wouldn't feel much inconvenienced by stepping the mast right on the deck instead of pivoting it in a tabernacle. PocketShip's mast is short and not very heavy. Someone of just-below-average fitness is strong enough to hoist it upright without the aid of a tabernacle. If a racing class of PocketShips ever evolved, the top boats would all shift to deck-stepped masts.

The deck would need to be reinforced. Some months ago I did up a drawing of how I'd do it. This BBS is a little weird about displaying images, but here it is:



The mast length is increased 3-3/4" and the bowsprit reduced by 5". A sturdy section of 6-inch aluminum channel captures the butt of the mast and the bowsprit. To take the compression, a chunk of 2x4 spans Bulkheads 1 and 2 beneath the deck. This reinforcement would be entirely out of sight.

John, I love your replies because I always learn so much!

For what it's worth to other builders, I wouldn't even consider taking the tabernacle off my boat. It's extremely useful, and like John said, it takes me 10 minutes to launch at the ramp. That is one of the great things about Pocketship. One change I did make was to replace the boom gallows with a temporary crutch that sits into the mast step for my mizzenmast. At the ramp I remove the temporary crutch and store it in my car.

John,

Thank you very much for the thoughts and thoughtful next step design consideration.

For me, I have two options...the new tabernacle-less thought, as well as the option of reducing the height of the tabernacle (I am gleaning the option is there). I like the original design and the ease of rigging so I will let folks now how it goes. I plan to have a fixed tabernacle approximately 3" shorter maintaining all of the remaining geometry. The clearance over the cabin appears to be ample and I was considering a removable gallows anyway (yes...I know I should leave design to the pro).

Sorry to re-open this thread. Has anyone built a PS with a shortened tabernacle? This option seems much better than a removable one.

Cheers,

Peter

Just a couple thoughts on a lower tabernacle - seems like it could work fine, however some of its benefits would be slightly impeded. Mast would be a bit 'heavier' when lifting up, Mast alignment would be less ideal when lowered (would extend faster aft) and mast may not be level with the gallows (could lower them too?) when covered with a tarp etc. One other issue is the drop boards to the cabin would be tough to pull out when the mast and everything is down, as mine must be pushed a bit into the rolled up sails in order to lift it out. This could be easily solved with 3 sections, instead of two. Not sure what this may due to the forces/loading on the tabernacle while under sail, but seems a few inches lower would not have a significant effect. My 2 cents...