Tabernacle on H30?

Discussion in 'The Cherubini Hunters' started by Weekdaysailor, Aug 25, 2018. Add this thread to a FAQ

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  1. Weekdaysailor

    Weekdaysailor

    Joined Feb 15, 2005
    10 posts, 0 likes
    - -
    US San Francisco, CA
    I have a '78 and on waitlist for a slip that will require the mast be lowered.

    Anyone done this on an H30 with pics that can be shared? I have searched high and low and not found much and nothing on this particular model. I'm looking to tilt fore not aft.

    Thanks!

    -Keith
     


  2. heritage

    heritage

    Joined Apr 22, 2011
    531 posts, 106 likes
    Hunter 27
    US Cherry Point MCAS
    The Cherubini Hunters were not designed for the mast to be lowered, only to remove the mast. It's probably possible to lower the mast forward if you can figure a way to secure the bottom of the mast while lowering and move it to the rear of the boat. I recently had my H27 mast removed while in the slings with a crane on top of the travel lift. It's a complicated job even with a crane,,, wires inside the mast, stays, and furler to be tended to,, and it's heavy.
     


  3. dLj

    dLj

    Joined Mar 23, 2017
    341 posts, 140 likes
    Hunter 30
    US Snug Harbor, Lake Champlain
    On my '77 while rebuilding the mast last year I was looking at doing what you are asking about - in my case it would have gone backwards, not forwards. I don't think it matters. I decided it was too much work for what I need.

    However, I did put some thought into it. There is a base for my mast embedded into the deck, I think you'd have to remove that and attach it to your mechanism for dropping the mast. You could then make a hinge type plate with that base mounted on the top and permanently, or semi permanently, attach into the mast base. You'd then have to figure out a rasing/lowering system and storage position. The mast on my boat is mighty darned heavy. I seem to recall someone telling me it was in the 200 to 300 pound range. I don't know really how much it weighs, but from having to handle it during the rebuild, I'd guess that 250 pounds would not be far off the mark.

    Sorry can't give you much more than that. I opted to not build that system.

    dj
     


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  4. MitchM

    MitchM

    Joined Jan 20, 2005
    743 posts, 117 likes
    Nauticat 321 pilothouse 32
    US Erie PA
    lots of guys on the cape dory boards have fabricated their own tabernacle hinges ; you'd need to customize their designs to your boat. if you have to lower the mast 1x a year for haul in/out it would be easier to use a crane than build a tabernacle. if it's more than that, dropping/hoisting the mat could become really tedious.
     


  5. BlowMeAway

    BlowMeAway

    Joined Nov 30, 2015
    1,113 posts, 604 likes
    Hunter 1978 H30 Cherubini
    US Cayuga Lake, Ithaca
    Not a good idea to DIY. That’s a mighty tall and heavy mast. Our boat yard uses a Cherry Picker on a large truck to demast and restep every year. I can’t imagine a tabernacle strong enough, or an on deck lifting system stable enough to raise the mast without a whole bunch of circus tent professionals in attendance.
     


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  6. David in Sandusky

    David in Sandusky

    Joined Nov 8, 2007
    1,160 posts, 186 likes
    Hunter 27_75-84
    US Sandusky Harbor Marina, Lake Erie


  7. ggrizzard

    ggrizzard

    Joined May 27, 2004
    1,089 posts, 120 likes
    Hunter 30_74-83
    US Ponce Inlet FL
    Due to the design of the base plate, which is screwed down to the deck and holds the foot of the mast in place, it is not possible to rotate the mast forward or backward in place. It HAS to be lifted at least three inches to be removed. The internal wiring and the weight of the mast are two other reasons not to attempt this project.

    I have posted a few pics of my 1979 H30C in the "Owners" section of this forum. Click my user name, select "albums page" and see what's there. I will add some additional thanks to your request.

    If you have specific questions just send me a private message.
    G.
     


    Last edited: Aug 25, 2018
  8. Benny17441

    Benny17441

    Joined May 24, 2004
    5,747 posts, 416 likes
    CC 30
    US South Florida
    Not clear why the slip would require the mast to be lowered. Is there a bridge or obstruction to access the slip? The h30 is not the type of boat where it is practical or perhaps even possible to tilt the mast. A crane is usually required to drop that mast. If the problem is a foot or two the mast could be cut down. Rigging and the main sail would also need to be cut accordingly.
     


    Last edited: Aug 26, 2018
  9. Roland5048

    Roland5048

    Joined May 12, 2004
    1,184 posts, 381 likes
    Hunter Cherubini 30
    US New Port Richey
    If you have to lower the mast to get to your slip, are you going to have to lower and raise every time you go out? If so, not gonna happen. If this is a matter of a bridge you need to get under then, yes, like @Benny17441 wrote, you can cut down the mast. The expense, though, would not be worth it. IMHO, another slip or another boat.
     


  10. williamtl

    williamtl

    Joined Jun 1, 2015
    164 posts, 55 likes
    Macgregor 26d
    US rocky fork
    In the northeast of Poland they have a lot of interconnected lakes and a great sailing tradition. Their road/rail infrastructure never considered sailboats except in rare cases like a section of road that turns 90 degrees by hand. I digress.

    The majority of the boats have a tabernacle mast raising/lowering system. You can see it in the picture. It is the rail running just above the top sides, almost parallel to the water and follows the shape of the bow. It is hinged at the two aft points and a block and tackle system connects at the fore end, the apex of the bar.

    81307834-FEE8-4237-89B6-24FA74224657.jpeg

    The process to lower is disconnect the gooseneck and lay the boom to one side.

    Pull the lock pin which also has a safety ring at the base of the jib halyard (probably not the right terminology). There is a line that runs from the base of the jib halyard back to the cockpit. It runs through the blocks between the base and the attachment. It is the red with right tracer on the port side in this picture.
    1F25DAF5-53C1-4977-9032-FA7F30084818.jpeg
    This line controls the mast falling backwards. Ease it and a little push and down she goes.

    To raise, pull or winch the mast back up, pin it, reconnect the boom, and off you go.

    Here is another picture showing the mast laid down. The blue line with white tracer is the line that controls the mast.

    EDCE9545-7221-4D54-8AE2-9DBA83FDCA8F.jpeg

    A couple of the groups I sailed with got good enough to take this down in under five minutes. Could be done by one person, but it was always nice to get everyone involved even if some only helped wrangle all the lines and stays.
     


  11. Weekdaysailor

    Weekdaysailor

    Joined Feb 15, 2005
    10 posts, 0 likes
    - -
    US San Francisco, CA
    Hey all, thanks for the tips! [I switched emails so wasn't getting notified]. I did not mean to imply complete removal - this is just to lower it about 10' to clear a bridge which crosses the harbor, like so: (in fact, the exact harbor shown) Plenty of similar boats in the harbor, and I've taken pics of dozens. Layouts are all pretty similar. Mast base gets a pivot-pin, fore of mast sawed to the rotation curve. Back shroud has a quick release (anyone know a source for slip hooks? Google-fu not working), middle shroud gets a new pivot, in-line with base of the mast (so that it remains taut as mast lowers), fore-shroud just droops, furler/jib dropped to deck and swapped w halyard. Boom is used as gin-pole, stabilized w lines to mid-beam (I think this is the weak-link honestly; due to age of components), and lowered via the backstay rigged to the boom (either manual tackle or powered winch to control the drop). I need to pull my stick anyway (mast base plywood is crushed finally) and the rest of the rigging changes are non-destructive (i.e. if I never use it, no harm, no foul). I'll have plenty of opportunity to test in calm water. To talk myself out of it, I'll crew on the local beer-can races and see how gnarly it is in practice. Other challenge is finding a rigger willing to assist. Meanwhile, I'm floating at top of the waitlist and watching Craigslist to see if a better-suited boat shows up (but I *love* my H30) -K
     


  12. jssailem

    jssailem

    Joined Oct 22, 2014
    9,003 posts, 3,911 likes
    CAL 35 Cruiser
    US Salem, Moored Port Everett WA
    @Weekdaysailor that looks doable on a small boat. I would wonder about the 800 pound mast I have, and would seriously question such design in a San Francisco Bay storm. I would think that such a plan would mean staying out of the harbor until the storm passed and the weather was again calm.
     


  13. Weekdaysailor

    Weekdaysailor

    Joined Feb 15, 2005
    10 posts, 0 likes
    - -
    US San Francisco, CA
    Thanks @jssailem- Do you have concerns with the rig upright or just while lowered? Structurally, once upright and secured I don't see any reason it would be structurally weaker than now so long as I use quality components of correct size. Probably better since I'll be replacing some elderly parts.
    I think my mast is only in the 300lb range (old Kenyon I think) (plus weight of boom/main). Santa Cruz harbor is not in SF bay, but Monterey Bay - and the rig would be lowered for only about 50yards while crossing under the bridge. The harbor is wide on both sides and generally calm - main concern I would have is boat wake setting up an oscillation.
    Looked at some of the existing boats again yesterday - honestly from what I see my design will be significantly more beefy than most (saw lots of turnbuckle extensions out of stamped sheet, etc)
    Really appreciate all the discussion! -K
     


  14. jssailem

    jssailem

    Joined Oct 22, 2014
    9,003 posts, 3,911 likes
    CAL 35 Cruiser
    US Salem, Moored Port Everett WA
    Hi K-
    If I understand your plan. You intend to cut the mast at some point and attach hardware that lets you lower the mast to sneak under the bridge. Then you will be raising the mast back to vertical and sailing.
    My limited engineering experience says the mast will be weak at the point you make th cut.

    The mast serves to transmit the power of the sail to the keel. The point at which it is cut will now be a point of concern as the power of the sail has to transit through the cut to the mast base. The basic design is to have the mast base as the point of contact it is also the point that the stays pull down against. With the cut you now have to points for this force to affect. You will need to engineer the cut point so that it is stronger than the base.

    While it can be done use not sure that the expense and effort is worth it. That is only something you can decide. Bear in mind Mast all have weak points. Many of us modify our mast with out consideration. Then we get surprised when the mast comes down.

    Check out the following failure. We see this and laugh/cry at the event. Look at how the mast fails. That is based on the weak point of the mast. Why there and not at the base or the top of the mast?





     


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  15. Weekdaysailor

    Weekdaysailor

    Joined Feb 15, 2005
    10 posts, 0 likes
    - -
    US San Francisco, CA
    @jssailem thanks again. I should clarify this is already a deck-stepped mast (to wooden kingpost, to old rusty I-beam on keel), so just about 1/2 of the base is rounded off for the curve of rotation, so I agree the remaining base is shouldering more load. I have seen a few designs where an otherwise intact, keel-stepped mast is cut/hinged, but luckily I'm not facing that.

    The other boats I've looked at often have a (wooden?) plug inserted which, combined with the tube inserted for the rotation pin may be intended to help prevent sidewall collapse (which seems the likely failure mode). There's amazingly little documentation on these things considering how common they are (suspect buried in old Don Casey books that I need to dig through). But looking at the example boats I don't see any signs that the masts are bigger/thicker than usual (or conversely chopped down), otherwise reinforced, etc. They all look like normal production masts that were simply altered in the manner I described (many clearly aftermarket). Buying another boat already so modified may just expose me to someone else's poor engineering so that's why I'm leaning this way. Best option would be a documented, factory-modified rig. I'll keep looking
     


  16. jssailem

    jssailem

    Joined Oct 22, 2014
    9,003 posts, 3,911 likes
    CAL 35 Cruiser
    US Salem, Moored Port Everett WA
    Or You can boldly go forward and be an innovator. Design your own clever engineered idea and everyone will admire your creativity.
    It is a fun task.
     


  17. MikeHoncho

    MikeHoncho

    Joined Dec 28, 2015
    294 posts, 120 likes
    Laser, Hunter H30 Standard
    Un Tacoma
    It took me hours to tune my rig. I could get it down to a hour with practice. Assuming you would have to do this everytime?
     


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  18. sandpiper10471

    sandpiper10471

    Joined May 31, 2007
    708 posts, 6 likes
    Hunter 37 cutter
    CA Blind River
    Be really creative and turn her into a schooner! Or you could go the older British route and give her a gunter rig.
     


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  19. Weekdaysailor

    Weekdaysailor

    Joined Feb 15, 2005
    10 posts, 0 likes
    - -
    US San Francisco, CA
    They can be tuned?
    ;) I don't race, but with quick release (slip/Pelican hooks), and tensioner on the backstay I should be able to get it at least as sloppy as I normally run it in short order. Tonight I'll hang out for the beer can races and see about getting some first-hand experience.

    @sandpiper10471 I may very well get a 2-part mast, but probably not intentionally...