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Conversion - Reusing bermudian rig alu mast as a top mast in an alu alloy base?

  • 29 May 2014 19:50
    Quote
    Reply # 1558631 on 1557536
    Deleted user
    Thank you very much for your answers! Ok, I will not re-use my old mast as a top mast. This was just an "idea" that came up while having coffee in the morning the other day, and I wanted to explore it a bit... Actually, I will need help from an expert to make mast & partners decisions for me... I really don't want this to break in storms, because crossing the north Atlantic with my 22 feet Jonquette will be my next challenge. First sailing from Normandy to Plymouth this summer sounds like a good idea, hoping to meet experts from the JRA and see a lot of junk rigged boats in action! Right now I am starting to work on the sail. Raphaël
    Last modified: 29 May 2014 19:51 | Deleted user
  • 29 May 2014 05:40
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    Reply # 1558344 on 1557536
    Anonymous member
    Hi James - good that you can join in now.  Your mast idea is very interesting.  I look forward to hearing how it all works.  I see you have a Golden Hind 26 - I would think a junk rig would suit her very well.  Best of luck.
  • 28 May 2014 13:34
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    Reply # 1558026 on 1557536
    Anonymous member
    It looks like I can post on the forums at last!  (I wonder what changed...)

    Yes, I like the idea of reusing the old bermudian mast as a topmast.  Annie's right that it won't be strong enough for the lower part, but might be good for the top. 

    When I built my mast from scratch, I used alloy tubing for lower and for topmast.  I joined the two together (and gave a taper) by sheathing the topmast in wood - I used half-round fenceposts that I dug out roughly.  The whole lot epoxied together with microfibre thickener.  In my caution I allowed a full metre of overlap.  Picture in my photoalbum.

    Your job will be harder if the bermudian mast isn't round, but you could build up a sheath with epoxied laths of wood.  As well as padding out to fit the lower mast, this sheath will add strength to the upper part, and a nice taper.

    I should point out that my own mast isn't yet installed & tested in practice.  Still working on mast step and partners.

    Interesting project - whether it's worth it... who knows?

    Last modified: 28 May 2014 13:48 | Anonymous member
  • 28 May 2014 00:52
    Quote
    Reply # 1557887 on 1557536
    Anonymous member
    Raphael, generally, the drawback of using an existing spar are
    • The shape is incorrect: junk masts are generally circular because the loadings are fairly even distributed.  At least that's how I understand it
    • The existing spar has holes in it, from fittings, which create stress points
    • The wall thickness is inadequate.

    Ifyou can get around these factors, whether you could use the old mast would probably depend on how much of the spar will be required for the topmast as to whether you could get away with it.  The three abovementioned issues apart, to me the most difficult thing would be to create a smooth transition between the two masts, so that the batten parrels etc, won't snag as you haul and lower the sail.

    I don't pretend to have much technical expertise here, and hope that someone who does will discuss this matter more fully with you, but my comments may give you some food for thought.
  • 27 May 2014 08:27
    Quote
    Message # 1557536
    Deleted user
    Hi all,

    Currently working on converting my 22 feet Jeanneau Love Love to junk rig, I have to make a decision about the mast. I like the idea of combining an aluminium alloy base with a top wood mast. But, a question came this morning - From my "non engineer" understanding, most of the effort on the mast are at the partners, so, would that make sense to re-use the original aluminium mast of my Jonquette as a top mast that would be introduced in an aluminium alloy base?

    PS: Current mast has an oval shape - 125 x 80 mm.

    Raphaël
    Last modified: 27 May 2014 13:46 | Deleted user
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