26 foot catamaran for junk rig

Discussion in 'Multihulls' started by Pondlife, Jan 31, 2016.

  1. Pondlife
    Joined: Nov 2015
    Posts: 18
    Likes: 0, Points: 1, Legacy Rep: 10
    Location: Kent

    Pondlife Junior Member

    Hello,

    I have been thinking for a while of building a cat. I would like it to be dory hulled and demountable for ease of launching and recovering. I like the 'Janus' design but it is a bit small for my needs. Ideally it would be more like 26 foot. I am in the process of converting my boat to junk rig, in order to learn the art of sailmaking and spar making and would like to apply this to a cat in some form. I have trawled the net looking at various designs but cant seem to find the right one , probably because I am asking a lot.
    Any thoughts?

    Thanks Mark
     
  2. upchurchmr
    Joined: Feb 2011
    Posts: 2,873
    Likes: 89, Points: 48, Legacy Rep: 579
    Location: Ft. Worth, Tx, USA

    upchurchmr Senior Member

  3. Pondlife
    Joined: Nov 2015
    Posts: 18
    Likes: 0, Points: 1, Legacy Rep: 10
    Location: Kent

    Pondlife Junior Member

    I was considering a mast in each hull unstayed. Although the size difference between 26 and 28 might not seem much the work and cost is significantly more. I feel that 25-26 foot is all I can manage at the moment. Though for a boat that I can build all the components myself including the sails then I keep coming back to a Wharram. I know its not dory hulled but everything else is there. I might have answered my own question.
     
  4. Zilver
    Joined: Nov 2007
    Posts: 65
    Likes: 3, Points: 8, Legacy Rep: 14
    Location: Amterdam the Netherlands

    Zilver Junior Member

    Here's a dory hulled catamaran, demountable, with two unstayed masts(supports).

    http://www.ikarus342000.com/DUO800Spage.htm

    The designer will probably tell you that a junk rig on such a fast boat is not practical, but it has been done before.

    Cheers, Hans
     
  5. Pondlife
    Joined: Nov 2015
    Posts: 18
    Likes: 0, Points: 1, Legacy Rep: 10
    Location: Kent

    Pondlife Junior Member

    Cheers, Have many been built?
     
  6. pogo
    Joined: Mar 2010
    Posts: 342
    Likes: 9, Points: 18, Legacy Rep: 73
    Location: Germany Northsea

    pogo ingenious dilletante

    perhaps you should google " catamarans plywood biplane"

    in france the Designer Gilles montaubin Designs and Builds Multi-and monohulls with unstayed riggs.
    he has several trimarans with Ketch or Yale riggs and at least One Cat with a biplane rigg in his Portfolio.
    All his boats are ply/epoxy
    feel Freeto surf Thriller his Site
    https://chantiermer.wordpress.com/occasions/

    (As yu Shirley habe nötigend i actially use my Wolfes i Päd. Hahaha:D:(:mad:;)
    Scheissndreck ---med myself and i ; an analog native)

    pogo
     
  7. Richard Woods
    Joined: Jun 2006
    Posts: 2,179
    Likes: 145, Points: 63, Legacy Rep: 1244
    Location: UK, USA and Canada

    Richard Woods Woods Designs

    Thank you for your interest in my Janus design. Upchurchmr is right, I do have a couple of bigger catamarans with doryish hull. You can build an open deck Gypsy, or there is the Salish 28 (available with a longer cabin) or my new Eagle 24

    But a junk rig results in a horrible sailing boat. Even James Wharram tried it and gave up.
    For one thing raising an unstayed mast bigger than say dinghy sized is a real challenge

    Richard Woods of Woods Designs

    www.sailingcatamarans.com
     
  8. rob denney
    Joined: Feb 2005
    Posts: 722
    Likes: 84, Points: 28, Legacy Rep: 436
    Location: Australia

    rob denney Senior Member

    Not so. Raising an unstayed mast is simpler than any other type.

    Use a pole (length of 4" x 4" timber, old dinghy mast, piece of steel tube will do as the loads are small, only the weight of the mast acting directly down the pole) and insert it in a hole near the mast with the bottom fitting into a cup on the keel near the mast step. The pole minimum length is twice the bury of the mast.
    Tie a block and tackle on the top of the gin pole before insertion and tie the other end around the mast.
    Lift the mast until it is at the top of the gin pole.
    Grab the heel of the mast, swing it to vertical and lower it into the mast hole.

    No rigging to tangle, stays to bend, winching, stress or rigging screws to attach and tighten up. Nothing to break.

    If you don't like the deck hatch near the mast, rig a bi or tri pod on the deck and hang the block from the apex.

    There are faster, lighter, easier and cheaper ways to build dory hulls than plywood.
     
  9. Pondlife
    Joined: Nov 2015
    Posts: 18
    Likes: 0, Points: 1, Legacy Rep: 10
    Location: Kent

    Pondlife Junior Member

    I must have missed the eagle design, it looks a good little coastal boat. Is there a rig that could be used and self built? You mentioned before a planned gunter rig?

    Thanks Mark
     
  10. Richard Woods
    Joined: Jun 2006
    Posts: 2,179
    Likes: 145, Points: 63, Legacy Rep: 1244
    Location: UK, USA and Canada

    Richard Woods Woods Designs

    Pondlife. Probably it is best to email me direct for specific design questions. woodsdesigns@gmail.com

    Rob. Do you have photos and preferably a video of your unstayed mast raising system as I am sure everyone will want to see it. Especially how you stop the mast going sideways when hoisting it and how you get the mast out of the mast step again when lowering the mast after sailing

    You say it is simpler than any other type. I have seen someone raise his 50ft mast on a Farrier trimaran singlehanded while it was in the water. That must be pretty simple. So too is this (note the last 2 photos)

    http://sailingcatamarans.com/index.php/articles/11-technical-articles/268-safe-mast-lowering-method

    and this

    https://www.youtube.com/watch?v=1OjzcWl0h6k

    so please show us how your system is simpler, quicker, easier. Thanks

    Richard Woods of Woods Designs

    www.sailingcatamarans.com
     
  11. rob denney
    Joined: Feb 2005
    Posts: 722
    Likes: 84, Points: 28, Legacy Rep: 436
    Location: Australia

    rob denney Senior Member

    Richard,

    No videos, but I have raised a lot of stayed and unstayed masts, and as logic suggests, it is far easier and quicker with the unstayed ones.

    Imagine a crane picking up a mast and placing it in a hole in the deck. Then lifting it out.
    Replace the crane with a stick in a hole next to the mast with a block on the top and a tackle tied to the mast, through the block and back to you. Pull on the tackle to lift the mast, swing it vertical (if the attachment to the mast is below the cog) and lower it into place. Pull the tackle to lift the mast out of the hole, grab the base and lower it to the deck.
    This is simpler and less effort than either your video or photos. When horizontal, the mast is easily moved (the stick and block and tackle help if it is a big mast) and sits in chocks on the deck. Nothing to connect/disconnect apart from the rope around the mast, nothing to tighten up and no winching.

    "You stop the mast going sideways" by holding on to it. Unless there are big seas, this is not difficult as the mast is constrained by the block and tackle.

    "You get the mast out of the mast step" by lifting it vertically.

    Another option for boats that regularly pass under bridges is a hinge in the mast, just above the boom. This does require a winch (and some serious engineering), but is still less hassle than a stayed rig. Plus, neither the boom nor the sail need to be removed from the mast.

    We have just quoted for a 20m/66' unstayed mast suitable for a 9m/30' wide, 6,000 kg/6 ton cat. Weighs 130 kgs/286 lbs, costs $US17,000. Alloy and ss wire will not only be harder to raise and lower, with far more maintenance required, but will be heavier, and probably more expensive.
     

    Attached Files:

  12. Pondlife
    Joined: Nov 2015
    Posts: 18
    Likes: 0, Points: 1, Legacy Rep: 10
    Location: Kent

    Pondlife Junior Member

    Thanks Richard, look forward to seeing the Eagle build photos.
     
  13. Richard Woods
    Joined: Jun 2006
    Posts: 2,179
    Likes: 145, Points: 63, Legacy Rep: 1244
    Location: UK, USA and Canada

    Richard Woods Woods Designs

    I now I am being stupid about this but I still don't understand. Maybe the rest of you reading this do get it and can tell me, rather than Rob trying to explain it again.

    I said I watched a Farrier 32 owner raise his mast unaided while at anchor. Rob says his system is quicker and easier.

    So assume the mast is 45ft above deck and thus say 50 ft long. How long is the "stick"? how big a section? How do you hold it up? What do you do with it when you have the mast up? Clearly you don't want it on board any more.

    How do you hold the lifting strop in place? How do you get it up the mast when lowering it? Remember it has to be "easier" than the Farrier method, so that means you cannot go up the mast to fit it in place - that would make it harder.

    You say " no winching" but also say "use a tackle to raise it" To me that's the same as winching. I have raised many masts up to 35ft using just the mainsheet.

    For what its worth, the last three boats I have sailed all had unstayed masts. The largest was a Freedom 46. I'd like to see Rob "quickly and easily" lower that by himself with no outside help.

    Richard Woods of Woods Designs

    www.sailingcatamarans.com
     
  14. rob denney
    Joined: Feb 2005
    Posts: 722
    Likes: 84, Points: 28, Legacy Rep: 436
    Location: Australia

    rob denney Senior Member

    Google sheerlegs, see lots of pictures of bi and tripods lifting big weights. If that is too much information, try "pole erecting sheerlegs". Replace the bi/tripod with a stick in a hole alongside the mast.

    Maybe, if not, i will draw you a picture when I get time. I'd video it on my boat, but at the moment it is rigged for kiting and the mast is in storage.

    Perhaps if you went through all the stages involved in raising and lowering the F32 mast, it would help you understand what is involved. Start with moving it aft so the heel is at the mast step. Connecting the shrouds and getting the boom vertical and tied off. Running the line through the end of the boom, down to the forestay and back to the winch. Then winching it vertical, starting with a lot of low gear effort, attaching the forestay, removing the boom and attaching it on the gooseneck.

    Big enough to take the weight of the mast, in compression.
    Say the 50' mast weighs 80 kgs. A piece of 100 x 100 timber would suffice, as would the boom of the boat. The compression load on the boom used to conventionally raise a stayed mast is much higher than this.

    Length needs to be twice the bury, so min 10', plus a little, say 12'. COG of the mast is maybe 15' up. Tie the lifting rope off at 12' up from the bottom and lift the mast up. The heel goes up first, the tip stays on the deck. Everything is stable, or easily held in waves. Grab the heel, and pull it down until the mast is vertical.
    The load on it is, I think 20 kgs (80*(15-12)/12)) which is applied downwards so not a big deal. If this is too much or your weights and lengths are different, you need a longer stick. 20' stick, with the attachment at 15' up (COG) would be no load at all. Once the mast is vertical, lower the lifting line and the mast goes into the top bearing. May need a wiggle to get it straight, but the loads at this point are near zero. Keep lowering it until it is in the bottom bearing. Add boom and sail, go sailing.

    Read my previous post. It goes through a hole in the deck adjacent to the mast, and sits in a cup next to the bottom bearing.
    Put it on the mast if it is the boom, leave it on the dock, store it in the hull, tie it to the forebeam, telescope it or make it into sleeved sections if you are storage constrained.

    The lifting line is tied around the mast with a bowline. A second line is tied to the loop and tied around the gooseneck on the mast so the loop is 12' off the base. Once the mast is up, release the lifting line and pull it down the mast.

    Pull on the second line and down it comes. To get it in place to lower the mast, hook a halyard to it and pull the loop up the mast. Not exactly rocket science.

    You say " no winching" but also say "use a tackle to raise it" To me that's the same as winching. I have raised many masts up to 35ft using just the mainsheet.[/QUOTE]

    I was differentiating between light and heavy masts.

    Why? There is no difference between a long and a short mast except the length of the stick and how many purchases required.

    If it was set up for it, it is a simple procedure. If there is no hole for the stick and I had 3 pieces of 100 x 100 or similar 8' long , some string and a block, I could rig a tripod sheer legs in less time than it would take to move a similar sized boats stayed rig from lying on the deck to pinned at the mast base. Using a piece of rope and a deck winch (most Freedom masts are incredibly heavy), lifting the mast would be a simple winding exercise until it came clear of the deck bearing, when a bit of grunt may be required (see above about different weights etc). I'd probably need someone to wind the winch, but failing that, it would not be difficult to rig a set of lines to control the base.
     
    Last edited: Feb 7, 2016

  15. Steve W
    Joined: Jul 2004
    Posts: 1,809
    Likes: 57, Points: 48, Legacy Rep: 608
    Location: Duluth, Minnesota

    Steve W Senior Member

    A few years ago I spent a month cruising the gulf coast of florida with a friend on his 28ft Egret sharpie. When we were done we put the boat away in a storage lot and headed north for the summer. The boat is a gaff schooner rig with solid unstayed masts my friend had built out of clear NZ radiata pine he had bought from a big box lumberyard in Minnesota. I helped him strip the boat in preparation for pulling out on her trailer but when it came to pulling the masts he didn't need any help. We had removed the sails, gaff and all lines except the halyard which he pulled through to the masthead and tied the tail off to a cleat leaving plenty of slack and then stood with one leg each side of the mast, crouched down in a proper lift with your legs position and lifted the mast straight up out of the bury and sat the butt on the deck, then repositioned and tossed it into the water, like tossing the caber like I saw at the highland games as a kid, and then hauled it in with the halyard. We were tied up at his dock on a canal at the time. My friend was 70 years old at the time and said that raising the masts was just as easy. Could have been easier had the masts been hollow but they were reasonably light anyway even though solid. The main mast was about 55lbs and being gaff rigged was fairly short at around 26ft above deck plus bury. Probably closer to the size of the masts that the small cat the op is talking about with a mast in each hull and junk sailplan than the 50ft monster Richard mentioned. The masts could have been lighter if they were built birdsmouth style.
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.