Galion 22 conversion

  • 03 May 2018 08:52
    Reply # 6130874 on 5070195

    To me there are two major differences between junk rig and bermudian rig that make all the difference in heavy weather: the mast is bare and tapered high up and the vast majority of the weight and windage of the rig come down as the sail is reefed. This, I reckon, compares favourably with the windage of a roller furling sail, even when reefed, and the wire rigging.

    Before aluminium became commonplace, lots of small boats had fairly substantial wooden masts and galvanised rigging, in larger sizes than we would see in stainless steel today.  They also had solid wooden bowsprits, but they seemed to cope perfectly well.

    Most of the weight of a junk rig is relatively low down - even a tabernacle, which most junks don't have.

    My mainsail on Fantail, without its battens, weighed 10k.  (I took it as carry-on when I flew with it to Nelson, although one is only allowed 7k - that's how I'm so sure of it.)  On the other hand, when I took the old sails off, it was a real struggle to lift the bermudian mainsail and I recall the jib as being even heavier.  Yes, the battens add weight, but they are evenly distributed along the length of the boat and, again, when the wind gets up, the battens come down.  In extremis you can lower the rig down to deck level.

    However, all the above considerations are really in relation to where the weight and windage is in a lot of wind and it is this that has concerned me more than the overall weight of the rig.  A fine bow is another issue.  While it's not uncommon, when there is only one person on the boat, to see their weight in the bow cause the outboard motor to come out of the water, I can imagine that one might worry about a lot of weight in the bow causing it to 'pile drive' when going to windward in a chop.  In truth, one of the advantages of a single-masted junk is that the mast does come further back into the boat.  Certainly, if you feel that the bow is lacking in buoyancy, I can understand why you would keep the weight there to a minimum.  However, you can compensate by only keeping light gear up forward (anchor tackle apart).  It's always a temptation to fill up the space under the forward berths, but if you try and avoid this, I think you should be able to compensate for any extra weight you are loading into the bow by fitting a junk rig.

    It would be interesting to hear the experiences of people with a fine-bowed boat, who have converted to a junk rig. I wouldn't have called the Raven 26 full-bowed, and I certainly never noticed the weight of the rig up there, but I am not sufficient of an amateur designer to be able to critique the bow as compared with the Galion of Jami's and realise that a 26 footer might react differently, anyway.  However, Arne has had a couple of quite skittish little boats that seem to have converted very successfully to junk rig, and that would make me feel pretty optimistic about the Galion.

  • 03 May 2018 07:56
    Reply # 6130839 on 5070195
    Thank you all for your valuable views, of which Graeme managed to bring up my own concerns better than I could.

    I am not worried about the weight as such. What worries me is that it moves to different places than before. 

    My main concern is the weight at the bow. To my eye the Galion has a very narrow bow, which indicates easily shifted balance. This is very obvious as one goes on the foredeck: the outboard propeller is easily lifted above waterline.

    Last modified: 03 May 2018 07:57 | Anonymous member
  • 02 May 2018 23:17
    Reply # 6130389 on 5070195
    Anonymous member (Administrator)

    Annie – when making a major rigging change is it not important to know the weight of the mast? And also to be aware of another matter of equal importance - the centre of gravity of the complete rig? I would have thought this to be particularly true in the case of conversion from bermudan to junk rig where (a) there is now a yard and a set of battens to consider  and (b) there is the temptation to add a bit of extra sail area and mast height. I think Jami’s concern is valid.

    Arne is experienced in this area of rig conversion, and willing to share his experience, which is a great advantage for Jami (and the rest of us) and his “gut feeling” is worth at least as much as a page of calculations – but I notice that Arne does his calculations too.

    We need to be careful of “spin.”

    Winches, bottle screws and boom are all in the lower part of the rig, and might well be lighter in total than a tabernacle. The bermudan main and foresail are unlikely to be heavier in total than a junk “one sail” since contemporary thinking is that “you can carry a bit more working sail with a junk because it is easy to reef”. At any rate, I have not yet heard of a bermudan to junk conversion where the result is less total sail area.

    That leaves the bermudan mast/spreaders/roller furling spar/wire rigging – total weight and centre of gravity – to compare with junk mast, yard and battens. A free standing mast might have heavier scantlings than a rigged one. And I would not call junk battens “light weight”.

    The extra spars (yard and battens, usually aluminium) of a junk are quite heavy actually, and hoisted high where it matters a great deal. This is a weight and height which no-one would contemplate adding to the head board and sail battens of a bermudan rig.

    For a static comparison of a bermudan rig with a junk rig in heeling you need to work out total weight of spars/rigging x height of centre of gravity of the total rig. Annie seems to be suggesting that it goes without saying that a junk rig conversion will come out the winner in such a comparison, but I have doubts.

    When considering and rejoicing the advantages of a junk rig conversion, it seems to me better to do the calculations and put them up for review as Jami has done. It is curious to me that Jami’s calculation for the weight of an aluminium tube differs from Arne’s, but this is a question which can be resolved with certainty.

    I realise Annie is not suggesting to proceed with ignorance, and rather is just encouraging Jami to get on with the task and not get too bogged down on one detail. Just as a matter of interest, when I get my conversion done (which is also taking far too long) I am going to do just what Annie suggests and weigh the two complete sets of rigging – and also consider the height above deck of each of the components. I have done a rough calculation already, but it will be interesting to test it.

    (One thing amazes me though - that a mast/displacement ratio of 2.9% is "acceptable" (see Arne two posts below.) The proof of the pudding is in the eating, so I will not argue with Arne. But a ratio of 2.9% gives me (with a 3.5 tonne boat) over 100kg to play with, for mast alone! Perhaps after all mast weight does not matter too much. I would still want to know what it is though. I  calculate my proposed mast (from truck to deck partner) to weigh 52kg - a mast displacement ratio for me of 1.5%. Theoretically, from truck to keel: 62kg which gives me 1.8%.  Perhaps I should be worried it is too light. 

    My tentative conclusion is that Arne's "mast/displacement" ratio is not a very useful number unless comparing very similar hull types. It makes more sense to me to just compare the new rig with the old and try to keep the total heeling moment of the new rig as close as possible to the old. That means calculating total weight of rig multiplied by height of centre of gravity of total rig above some comparable point - eg either deck partners, or keel. And while on the subject - is it not also true that the centre of effort of a junk sail will be higher up than that of bermudan, adding further to the heeling moment?)

    Sorry Annie, I just feel like being arumentative this morning.


    Last modified: 03 May 2018 02:29 | Anonymous member (Administrator)
  • 02 May 2018 20:29
    Reply # 6130107 on 5070195

    I don't know why everyone is so obsessed with the weight of the JR mast. Have you actually weighed the original mast, plus its winches, its wire rigging, bottlescrews, roller furler, boom and winches, foresail, mainsail, running rigging?  You are replacing all that with a larger mast, one sail, a yard and some lightweight battens.  Why not start making the sail while you wait for things to warm up and cut and whip the running rigging? 

  • 02 May 2018 10:53
    Reply # 6129168 on 5070195
    Anonymous member (Administrator)

    Jami.

    The mast is not ' somewhere around 50-60kg'. It is exactly 45, 46, 47 etc. The weight is easy to calculate, and I suggest you do that before you do any changes.

    My 1400kg Viggen, Malena had a wooden mast of around 70kg. Its weight and windage surely was on the high side, but Malena still coped and sailed around with that mast for 15 years.


    Arne

    EDIT: I already calculated the weight of that sort of mast to be 45kg (see posting 13. Mars). In the Sailboat data the Gallion's disp=1542kg.

    The mast/disp ratio should then be 45/1542=2.9%, which is fully acceptable, in my view.

    Last modified: 02 May 2018 17:02 | Anonymous member (Administrator)
  • 02 May 2018 09:00
    Reply # 6129093 on 5070195
    I'm sorry, but I still have to ask about the mast specifications one more time...

    I'm a bit worried about the weight of the 130x5 + 100x4 mm mast. Without the sail, battens, mast cap and running rigging, the weight is somewhere around 50-60 kg. This seems a lot compared to 1400kg displacement, the placement of the mast quite forward and the narrow bow of the Galion.

    Does the weight sound a lot or am I (again) worried in the wrong things (which happens easily when you have too much time (see below) to worry).

    PS. It seems that there is also 120x5mm tube available. This would save some kg's and make the transition between the two tubes smaller. But would I drop under the safety line with this?

    Last modified: 02 May 2018 09:05 | Anonymous member
  • 01 May 2018 08:19
    Reply # 6127482 on 5070195
    Just a quick update, in case someone is interested in my conversion:

    The spring here seems to be the longest, coldest and wettest for as long as I can remember. All of the epoxy work (including the ones unrelated to the conversion, eg. the bottom job and keel repair) is still waiting for the moisture to drop and temperatures to rise permanently above +5 Celsius. Very frustrating.

    In the meantime I have been cutting all the plywood parts needed for the partners and mast step. Now it seems this too is done. This leaves me only the job of sitting in the cold boat planning future interior projects and dreaming of actually sailing...

  • 15 Apr 2018 09:45
    Reply # 6099726 on 5070195

    Following on from Annie's comments, it's also a good idea to wear at least a filtering face mask, better again an activated charcoal model and full enclosing eye goggles when mixing epoxy or adding fillers.  The fumes from the epoxy getting into your lungs can also cause a reaction and the dust of the filler material won't be good for your lungs or eyes either. 

    Nowadays, unless I can work outside, I use a vacuum cleaner with a long hose to suck away the fumes and dust while I'm working with epoxy.  Especially when you're installing the mast foot.   

  • 15 Apr 2018 01:57
    Reply # 6099529 on 5070195

    I hope you are managing to keep the allergy at bay.  Try and work cleanly: minimise getting epoxy on your skin, and, especially on your tools, which you may well pick up later with unprotected hands, while the glue is still uncured.  Attach a vacuum cleaner to your sander, whenever possible, and at least use a bag on it if you can.  Wash your hands every time you've been handling epoxy.  Wash off the amine bloom if you can feel it.  Change out of your work clothes when you've finished for the day.  When all else fails, use a tiny amount of steroid cream if you find a rash developing.  Keep your work space clean so that you are not constantly stirring up epoxy dust.

    There's no such thing as fully-cured epoxy.  However carefully you measure it and however carefully you mix it, there will always be molecules of hardener that didn't bond with their resin partners.  As soon as you cut, plane or sand, some of these will get into the atmosphere.

    At the end of the day, I think some people are more susceptible than others.  Thus far I am one of the lucky ones.

    Your boat is coming along well: I'm sure you'll be sailing this summer and I look forward to seeing the photos.

  • 14 Apr 2018 05:20
    Reply # 6098649 on 5070195

    Mast step coming along; the hull shape is steep and starts to narrow very fast at the point where the mast will be. To me the best solution seemed to be using vertical slices of 12mm plywood, which will be epoxied together as well as to the hull.

    In the end 26 slices felt enough.

    Will there be more ply or steel on top of these to secure the mast, is still under debate in my head.


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    Last modified: 14 Apr 2018 05:21 | Anonymous member
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