Dropdown Longshaft for Wharram Catamaran

Discussion in 'Diesel Engines' started by Chris Bretter, Dec 8, 2008.

  1. Chris Bretter
    Joined: Nov 2008
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    Chris Bretter Zaphod

    Hi Manie what line are you in.If you come down to gateway in Durban i will be working right through.Pop in for Coffee Regards Chris
     
  2. Manie B
    Joined: Sep 2006
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    Location: Cape Town South Africa

    Manie B Senior Member

    Chris we will pop in - cool bananas :D

    i am in building and construction - that is why i am so f@cked in the head :D :D :D

    anyway i have done a sh1tload of research and it is honestly a case of the further i travel the less i know - however feel free to post any question and i will give my 2 cents worth - please list your suppliers BEFORE you pay good money, we may be able to steer you in better directions :idea:
     
  3. Manie B
    Joined: Sep 2006
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    Manie B Senior Member

    Hi Chris

    I am always fascinated / intrigued by what and why somebody wants to build a certain type of boat. I fully understand that there are strokes for folks - everybody has got their own specific needs and budget AND application.

    As i am deeply involved with my own building program and vast experimental comings and goings (which comes at a price as well) - i keep a constant lookout for new things because i am petrified that i have missed something crucial. I am working on the ultimate folly -which is going alone - because either i go alone or not at all, as my family does not share my views / dreams. In short what turns me on leaves them cold. My children are adults, my wife a corporate career girl and i am an entrepeneural party boy:D

    I am totally committed to epoxy and plywood - all my experimentation - as well as my final build which will start next year - is committed to ply and epoxy.

    I am very curious as to why you have gone Wharram.
    I have just gone over the TIKI 38 website - looked at most of it - and still ask why???

    For the benefit of the doubt maybe you guys have picked up on something we dont comprehend - so I would love to know more from you and your actual usage of such a vessel

    I fully understand that this becomes a VERY personal issue however we are all still boat fanatics with by and large the same dreams.

    So here goes a couple of basic questions

    Cruising across the BEEEG pond or day sailing in and out of the harbour
    How many souls on board and ages (kids are special)
    Simple budget - empty hull/deck - sails/mast - navigation/electronic equipment - living/household equipment - motors

    dont worry about accuracy, just get a general feel first

    and very very important - is resale value important to you or not

    last but not least - how much sailing have you done?
    and your mate, that will build for you, can he get you onto a Wharram for a couple of days?

    Hopefully i will be starting from step one next year with Chris Bonnet, Sunsail there in Durban - to do my proper licences - the whole flippen lot from yacht hand up to Yacht Master and so on. So yes i could buy you a beer every now and then, who knows:D My minicat is actually a half scale model of my basic thinking in line for my 12m cat next year. i am learning every day:D
     
  4. Chris Bretter
    Joined: Nov 2008
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    Chris Bretter Zaphod

    Well firstly i am a poor white boy so i need to keep costs down really low,I am good with my hands and being an old diesel mac need a simple wet sleeve motor and mechanical trans.I sailes Hobi 16s for a while other than that not much past day sailing.I like the simplicity of the wharram and have watched my friend Mushroom build 5 of them over 15 years all are still sailing with no sea worthy problems.I know one guy who is old cruiser who sails anything but will only own a wharram.I have sailed on his one only.
    Only for 4 people at a push.Will be sailed by my girlfriend and I.Minimal electronics.12 v electrics solar panels big charger.I will have to earn cashola as i go so will have to carry my tools of the trade.The current costing on the bare boat with no sails,head,cooker ,anchors,rode R340K.Which i think i can afford in the current situation.(barely)Just recieved my plans last week.Ease of maintainance is what i like as well as the flexing hulls.Mabe i am an ageing hippie(really im a metal head but whos to know)Perhaps its his brochure with the neked chicks)
     
  5. Manie B
    Joined: Sep 2006
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    Location: Cape Town South Africa

    Manie B Senior Member

    Chris to me it all seems ok:D

    i dont particularly like your choice of boat - but however the fact remains that there are a lot of them sailing around the world, if there were serious fatalities it would have been all over the web by now.

    i am an EASY fan but that doesn't mean that that is right either - i just feel that a bridge deck cat could be set up very well for single handling, and that is what i am experimenting with my half scale minicat5.

    i like your budget - i think it is do-able
    ply and epoxy is priced OK in RSA
    rigging can all be gaivanized including steel mast
    keep interiors simple
    i for one am going to stay away from extravagant over the top "creature comforts"

    i know that the world has gone crazy on "electronics" - half of which belongs on a "volvo racer" not a cruiser

    anyway start a new thread called building a Wharram when you are ready to order materials and i will post web pages of what i have found - experimented with - and recommend

    here are some posts showing all the mischief i get up to with epoxy and ply and pics of a boat AND trailer i built last year

    http://www.boatdesign.net/forums/boat-building/epoxy-second-layers-solution-25128.html

    http://www.boatdesign.net/forums/boat-building/minicat-5-a-24096.html

    http://www.boatdesign.net/forums/open-discussion/what-have-you-done-weekend-23233-29.html#post238127
     

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  6. Chris Bretter
    Joined: Nov 2008
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    Chris Bretter Zaphod

    I like a sextant and a sounding lead.A big anchor with chain.Lots of water and bean sprouts.I dont drink and eat little meat.The bouat comes with an ally mast and Galv Rigging.Price is really important as i really cannot afford this.But i got to do it afore im old.Older!!!
     
  7. Chris Bretter
    Joined: Nov 2008
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    Chris Bretter Zaphod

    That picture is your minicat. really cool.Designed and built by you.The wharram has a high bridge deck to stop pounding.but the construction method very similar.Lower hulls upside down then turned and topside fitted.
    your garage looks to neat to build boats.
     
  8. boat fan
    Joined: Sep 2008
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    boat fan Senior Member

    Sounds like a good plan Chris , just do it !:D
     
  9. marshmat
    Joined: Apr 2005
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    Location: Ontario

    marshmat Senior Member

    I concur.

    Build, sail, enjoy. That's what it's all about.

    As to Wharrams: Well, yes, they're weird. Wharram-bashing has been trendy ever since he built the first one in, what was it, 1955? But there's nothing terribly new or unorthodox about them. All he did was to apply some modern materials and mathematics to designs that have been criss-crossing the Pacific for thousands of years.

    Wharram himself cautions that a lot of his designs (there are a few thousand examples out there) have been built badly; see page 72 of his design book:
    But the same could be said for any design that appeals to home-build, low-budget adventurers.

    I don't see anything wrong with a lack of electronics, the use of galvanized rigging, etc. as long as you build a sound, solid hull. Longstanding commercial practice, not current trends in racing, should be the guide for someone planning to build a cruising boat on a tight budget.

    Best of luck, and do keep us posted :)
     
  10. Chris Bretter
    Joined: Nov 2008
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    Location: Durban

    Chris Bretter Zaphod

    Hi Matt
    The friend who is building it has built 5 already in 15 years only Tiki 38s This will be 6.He really understands the design.To many builders modify the boats radically.there are pieces that are structural which dont appear to be and weight is also an issue They are solid simple boats which flex We are raising the cabin height 4 inches all thru Regards chris
     
  11. sabahcat
    Joined: Dec 2008
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    Location: australia

    sabahcat Senior Member

    I have a tiltable/steerable Yanmar S2 leg that I was going to use in a sailing cat.

    These are used on boats that have a centre pod with diesel engine and works like a sonic drive.

    It is a bit short for a vessel with high bridgedeck clearance, but an appropriate sized mast section is used to extend the leg and then shafts get cut and sections added in.

    These have been commonly used on Fastback (Australian) sailing catamarans with great results

    If interested, I can be contacted on sabahcat@gmail.com
     

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  12. marshmat
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    marshmat Senior Member

    That might work, sabahcat.

    Chris- good to hear you have someone who knows Wharrams. His design philosophy works, but it's a bit unorthodox and seems to stump some builders who are expecting more 'conventional' ways of doing things.

    I'm still trying to figure out, though, how one would handle a single-engine cat that's as wide as these things. Everything I've read about handling big cats under power says that the primary method of controlling them in harbour is to oppose the shifters, and steer with gearshift and throttle....
     
  13. sabahcat
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    sabahcat Senior Member

    One I have sailed on in Brisbane, ten years ago arguably the fastest around (a 40ft foam kevlar epoxy suppershockwave with pre-bent rotatating carbon mast) has the single leg with linkages coming up to a vertical lever that travels port to starboard.

    This is at foot level at the steering position and they stuff it into a fairly tight berth, sometimes in big crosswinds seemingly with ease.

    They steer the motor with the foot and can have rudders and engines in opposing directions allowing some impressive crabwalking and pirouettes.

    Pics of boat and berth, pink line is about where the mud dries to at low tide
     

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  14. Chris Bretter
    Joined: Nov 2008
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    Location: Durban

    Chris Bretter Zaphod

    Hi Matt.The wharram is all i can afford really but i am fortunate to like them and have a friend who can build them.I was hoping to be able to use a ducted prop with a balanced rudder to steer.the rudder could be linked to the Steering system.I was hoping that someone could give me some advice on this site.regards Chris
     

  15. sabahcat
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    sabahcat Senior Member

    Makes sense:confused:
     
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