Jarcat 6 verions, modifications etc.

Discussion in 'Multihulls' started by waterbear, Jun 28, 2019.

  1. waterbear
    Joined: Mar 2016
    Posts: 56
    Likes: 14, Points: 8, Legacy Rep: 10
    Location: Alameda, CA

    waterbear Junior Member

    I've been looking at the Jarcat 6, thinking I could shorten the cabin and have a ginormous cockpit, as well as a nice big head in a trailerable boat. On the Jarcat the mast is located very far aft, so shortening the cabin would allow the mast to move forward and make for a more normal rig, which I'm guessing is a good thing.

    Anyway, looking at pictures I noticed some Jarcat sixes have nearly plumb bows and a different cabin shape, but most do not. I know there have been revisions, mk1, mk2, etc, but the current website has no information on this. One ad for a Jarcat with a plumb bow described the boat as 21', not 20 (6m), and it does look a bit longer.

    Anyone know if the plumb bow is in the current plans?

    Jarcat 6's with nearly plumb bows:

    8 jarcat 2.JPG 1.jpg maxresdefault.jpg


    And the other variant:




    J6layou2.jpg IMAG3856-781716.jpg IMGP0793.JPG
     
  2. waterbear
    Joined: Mar 2016
    Posts: 56
    Likes: 14, Points: 8, Legacy Rep: 10
    Location: Alameda, CA

    waterbear Junior Member

    And here I chopped some of the cabin off with photoshop.


    jarcat_shortcab.jpg
     
  3. oldmulti
    Joined: May 2019
    Posts: 502
    Likes: 304, Points: 63
    Location: australia

    oldmulti Senior Member

    Best bet is to speak to the Australian agent Don Nicholson who has great experience in Jarcats. He can be contacted via the Jarcat web site. Jarcats are very well thought out timber structural designs and any changes will often add work by needing reinforcing structures added etc. Also look at Richard Woods Chat 18 design, it may suit your needs. The designer of Jarcats died years ago and his son cleaned up the plans but is not involved on a daily basis in the design.
     
  4. waterbear
    Joined: Mar 2016
    Posts: 56
    Likes: 14, Points: 8, Legacy Rep: 10
    Location: Alameda, CA

    waterbear Junior Member

    Thanks oldmulti, I'll do that.

    Structurally I'd probably just duplicate the area under the mast, moving it forward/backward. The backward beam section could split the cockpit and support a traveler. I haven't seen the plans so I'm just speculating.

    Also I did see the Chat, but I like the bigger size of the jarcat. The Jarcat cabin extends over the hull, making a tall vertical space for a head and other stuff. The lowest point of chat's cabin is the bridgedeck, so using a head would be challenging.

    Jarcat's cockpit extends all the way to the stern, allowing more cockpit space. Chat's hulls are narrower with less waterplane area in the stern. Because of this I think RW wants to keep people out of the end of the boat, so the cockpit ends short of the stern, reducing party space. The outboard version (skoota 18) has volume added in the stern to prevent squatting under the weight of a 100lb outboard.
     

    Attached Files:

  5. guzzis3
    Joined: Nov 2009
    Posts: 474
    Likes: 36, Points: 28, Legacy Rep: 42
    Location: Brisbane

    guzzis3 Senior Member

    I see you have found boatdesign. I won't repeat what I said elsewhere.

    It is possible looking at the photos the boats you show with overhangs are actually J5s not 6's but I could be wrong. I don't know if the plans were ever changed there, my memory isn't that good, but it would be a trivial change to make.

    Part of the reason to keep people away from the extents of the boat is these are all very small light boats and will move a lot if someone is positioned near a corner. When I drew my larger hirondell size mini bridgedeck I had about a meter there. It accommodates the tillers nicely, moves the outboard forward and I drew sugar scoops, handy for getting off and on.
     

    Attached Files:

  6. guzzis3
    Joined: Nov 2009
    Posts: 474
    Likes: 36, Points: 28, Legacy Rep: 42
    Location: Brisbane

    guzzis3 Senior Member

    I do remember the mk2 J6 had the hatches further outboard to allow standing up in the hulls head poking out but for more detail than that ask one one of the jarcat forums.
     
  7. waterbear
    Joined: Mar 2016
    Posts: 56
    Likes: 14, Points: 8, Legacy Rep: 10
    Location: Alameda, CA

    waterbear Junior Member

    Both of the boats with plumb bows are called Jarcat sixes by their owners.

    When underway the rear of the cockpit isn't really useful because of the tiller, but when moored the tiller can be moved out of the way and the space can be useful. The Jarcat has a ton of waterplane area in the stern so it should move/squat much less than chat.

    Neat hirondelle. Looks a bit like skip allan's wildflower (which I think is actually a lengthened Jarcat with a different cabin).
     
  8. waterbear
    Joined: Mar 2016
    Posts: 56
    Likes: 14, Points: 8, Legacy Rep: 10
    Location: Alameda, CA

    waterbear Junior Member

    will do.
     
  9. oldmulti
    Joined: May 2019
    Posts: 502
    Likes: 304, Points: 63
    Location: australia

    oldmulti Senior Member

    Waterbear. If you can, contact a Californian guy by the name of Howard Spruits. He built the Yellow Jarcat in the initial set of photo's. He modified it from the 20 foot Jarcat to a 18 foot boat. He subsequently built a 22 x 8 foot catamaran for Skip Allen called a Frog 22 which uses some of the Jarcat build techniques.. Photo below with Howard standing in front. Skip moderates a single handed sailing forum where he give details of the Frog 22 and Howard's building input.
     

    Attached Files:

  10. waterbear
    Joined: Mar 2016
    Posts: 56
    Likes: 14, Points: 8, Legacy Rep: 10
    Location: Alameda, CA

    waterbear Junior Member

    Thanks oldmulti, I am aware of Howard Spruit. He's about 1.5 hours south of me, I might try to contact him at some point if this idea sticks. just started thinking about this a day or two ago, odds are I will lose interest and start thinking (aka obsessing) about something else.

    Mostly I just want a trailerable party boat with lots of deck space that can be sailed on the SF Bay. I was looking at the Chat 18 and the strike 18, hard chine wizard with no cuddy (suggested by guzzi). One feature I really want is enough space for a head, and many small boats fall short on this. I also want something easy to set up, so demountable cats are out. I understand narrow catamarans like Jarcat are not optimal Bay boats.

    Regarding wildflower, I assumed it was just a stretched Jarcat with a different cabin and the mast moved forward.
     

    Attached Files:

    Last edited: Jun 29, 2019
  11. waterbear
    Joined: Mar 2016
    Posts: 56
    Likes: 14, Points: 8, Legacy Rep: 10
    Location: Alameda, CA

    waterbear Junior Member

    I think the plumb bow Jarcats are just j6's with some material added to the bow. In my first post you can see they don't trim flat (photos 2&3), unless two people are standing on the bow (photo 1). So maybe this is just a modification that is not fully baked.

    Also one of these boats is from Florida, the other is from gulf shores Alabama (which is on the Florida border), so perhaps the builders knew each other.
     

    Attached Files:

  12. guzzis3
    Joined: Nov 2009
    Posts: 474
    Likes: 36, Points: 28, Legacy Rep: 42
    Location: Brisbane

    guzzis3 Senior Member

    That hull is entirely my own work and I put a lot of thought into it. It is specifically designed to be built in foam over one reversible mold. Everything else is flat panel, but hopefully not too ugly. Increasing the length and beam of a mini bridgedeck by 1/6 gave standing headroom in the cabin and a massive increase in carrying capacity. That boat is 23' long and 9'6" wide so in queensland could be trailered legally. It would be a safe coastal cruiser. I abandoned it when I realised the trailer regs had not been standardised across australia so it can not be easily trailered in NSW. Blessed bother.
     
  13. waterbear
    Joined: Mar 2016
    Posts: 56
    Likes: 14, Points: 8, Legacy Rep: 10
    Location: Alameda, CA

    waterbear Junior Member


    That sucks. At least you didn't build the boat and then find out.

    I think it looks quite nice. The hulls look quite fine, I imagine you didn't intend to carry heave loads?

    Btw, I've been to the gold coast and Cairns, and I would never want to tow an oversized load on some of the roads I encountered. There were some very narrow roads north of Cairns with some very crazy RV drivers that would surely take the side off your oversized cat.
     
  14. waterbear
    Joined: Mar 2016
    Posts: 56
    Likes: 14, Points: 8, Legacy Rep: 10
    Location: Alameda, CA

    waterbear Junior Member

    Oldmulti,

    I heard back from Don and he couldn't shed any light on the bows.

    Then I found the Yahoo group and searched for info on piccolo, and someone mentioned the bows being a modification. Someone else mentioned piccolo was built by Jorn Curtiss of Florida in the mid 90s. The yellow windowless boat came later so they must have copied piccolo.
     

  15. oldmulti
    Joined: May 2019
    Posts: 502
    Likes: 304, Points: 63
    Location: australia

    oldmulti Senior Member

    Waterbear and Guzzis3. Glad you contacted Don, a good guy. Guzzis3 I know of a 22 x 10 foot cabin cat that is trailed in Victoria. All that is required is an annual daylight permit for Victoria, the same applies for NSW. Mike Waller yacht design studied the road rules on the east coast of Australia and designed the TC 750 a cabin catamaran that is permanently 25 foot long x 11.45 foot wide that fit the road rules with cheap yearly state based permits. I tow a 23 x 8 foot caravan around Australia and have no problems. It just takes practice and some sensible planning. Guzzis3 your design looks good I hope you build it, the road rules are not as limiting as you think.
     
Loading...
Similar Threads
  1. jcjglt
    Replies:
    4
    Views:
    2,886
  2. neomastino
    Replies:
    29
    Views:
    29,576
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.