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  • 06 Oct 2019 21:30
    Quote
    Reply # 7920231 on 7919223
    Anonymous member
    Frederik wrote:

    Here we go...


    Fantastic to see the work starting, Frederik.  I am so looking forward to seeing your boat take shape.
  • 06 Oct 2019 17:38
    Quote
    Reply # 7919990 on 7155071
    Anonymous member

    Hi Arne. Behnke epoxy. From 5 celcius up. 

    When it gets too cold, I’ll do the frame glueing indoors. 

    Last modified: 06 Oct 2019 17:39 | Anonymous member
  • 06 Oct 2019 15:46
    Quote
    Reply # 7919871 on 7155071
    Anonymous member (Administrator)

    Hm, Frederik,

    that tent doesn’t look like a warm place during winters in Denmark. Have you found a glue that will work down to frost temperatures?

    Arne


    Last modified: 14 Feb 2020 21:53 | Anonymous member (Administrator)
  • 05 Oct 2019 21:33
    Quote
    Reply # 7919223 on 7155071
    Anonymous member

    Here we go...

    1 file
    Last modified: 05 Oct 2019 21:35 | Anonymous member
  • 11 Feb 2019 02:16
    Quote
    Reply # 7157082 on 7156352
    Deleted user
    Anonymous wrote:

    Taking the maximum rightning moment of the boat as starting point of the mast calculations  makes the most sense to me.  Times 3 as safety factor. Eric Sponberg does the same.

    Then again... what about the mizzen mast....


    Sponberg's article on designing free standing masts:

    https://www.ericwsponberg.com/wp-content/uploads/design-engineering-masts.pdf

    1 file
    Last modified: 11 Feb 2019 02:21 | Deleted user
  • 10 Feb 2019 15:24
    Quote
    Reply # 7156352 on 7155071
    Anonymous member

    Taking the maximum rightning moment of the boat as starting point of the mast calculations  makes the most sense to me.  Times 3 as safety factor. Eric Sponberg does the same.

    Then again... what about the mizzen mast....


    Last modified: 10 Feb 2019 15:24 | Anonymous member
  • 10 Feb 2019 13:07
    Quote
    Reply # 7156219 on 7155556
    Anonymous member (Administrator)
    Anonymous wrote:

    Thanks for the replies.

    Arne. 

    Are you using modulus of rupture in your calculations? For a 310/62 mm hollow spruce that would be 72 Mpa with a breaking strength of approx. 16300 kpm...



     I picked the strength of spruce from Ian Nicholson's Boat Data Book.

    There were three numbers to pick from, tearing force, crushing force and breaking force. Not knowing what to choose, I picked the 'weakest' one, the crushing force at 45MPa. If I had chosen 71MPa instead, then the breaking moment would rise from 11600kpm to around 18500. I have later looked up data about wood, and my 45MPa are most probably on the low side. However, I have just used local trees for masts, not knowing how good quality they were, so I my thinking was 'Better safe than sorry'...

    Arne

    PS:
    As early as in 2006, I had a go on finding the strength of wooden masts. I have later 'refined' the way to guess the righting moment of the boat, but apart from that, the write-up still makes some sense, hopefully. 
    The uncertain factor is the strength of the wood material.

    Last modified: 10 Feb 2019 13:37 | Anonymous member (Administrator)
  • 10 Feb 2019 08:34
    Quote
    Reply # 7156107 on 7155071
    Anonymous member

    Hi David. 

    We have thought about the schooner rig for quite some time.

    In the end I went with the yawl version hoping/thinking better performance and cheaper to build. 

    An early version of the schooner looks also very nice...

    1 file
    Last modified: 10 Feb 2019 08:39 | Anonymous member
  • 10 Feb 2019 08:22
    Quote
    Reply # 7156104 on 7155071
    Anonymous member

    Hi Annie. I haven't decided yet whether to go ahead with the build or not. There are a couple of things that need to fall in place. I want to be able to finish in four years and my budget would be around 35 k euros.. So before I jump in I want to be sure that it can be done within my limits.

    So far she's staked out in the garden..


    1 file
    Last modified: 10 Feb 2019 08:26 | Anonymous member
  • 10 Feb 2019 07:58
    Quote
    Reply # 7156102 on 7155071
    Anonymous member

    Here's another sketch from Chris Morejohn of a 34ft boat with a junk schooner rig. 

    This puts the foremast into the space ahead of the double berth, rather than through it. With a schooner rig, similar to the 34ft Benford dories, it gets much easier to find or make masts. What's the thinking behind putting most of the sail area into one large sail, Frederik? I found 54sq m a bit much to handle, which is why I went back to a ketch rig.
       " ...there is nothing - absolutely nothing - half so much worth doing as simply messing about in junk-rigged boats" 
                                                               - the Chinese Water Rat

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