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Mark Pearse

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Posts posted by Mark Pearse

  1. Hi Vaddoc

     

    very nice, she looks absolutely lovely.

     

    One small technical point, but my option only - I see that you have reduced the tackle on the forestay, giving a smaller ratio. I think that this is probably more likely than the earlier photo that seemed to have 4:1 ratio or so. With this sort of rig you take up the slack in the forestay & not tighten it a lot, the forestay tensioning is done by the mainsail pulling back against the forestay. You shouldn't tension the forestay because the load pulling aft from the mainsail would vary a lot depending on the angle of sailing, even in a constant breeze. 

     

    Mark

  2. Hi everyone,

     

    I'm wondering what techniques others use to sand completed planking, where the basic planking lines are good but there is a certain amount of fairing to get down to a faired shape. The planks I've used are around 2.5mm thick, & most will be at least 2mm finished after final sanding with a few parts slightly under that, at maybe 1.75mm.

     

    I was thinking of gluing sandpaper on to some flexible strips - maybe 1mm styrene or thin flexible ply - & sanding at various angles. The strips sized for one hand or two hands ..... so that I remove outstanding timber & not sand down where it's not needed. 

     

    Forum title searches unfortunately didn't really find anything that matched what I'm looking for.

     

     

    ideas ?

     

     

    thanks, MP 

  3. Hi Jim

     

    on reflection, it seems logical to me that it is a toilet: as a pearler they might have had something more basic for the crew, but it's hard to imagine them being able to take paying female passengers without having something discrete. Definitely close enough to the sea for a bucket & chuck it... So a simple way to fit a toilet is just to put one on deck in a convenient location. And looking at the rig setup, it's probably the only spot left.

     

    On the screens, an interesting comparison might be a common detail in some tropical Queensland houses: there are plenty of insects but the living areas use a "blow in blow out" insect technique, louvre windows without screens all around & the bugs blow right through, they seemed to value ventilation more highly than a mossie-free room. 

     

    MP

  4. The planking getting close to where stealer planks are needed, I'll probably do one more each side up from the garboard & maybe 3 or 4 more each side down from the gunwales. The planking is ok, a few wobbles, I'm just not sure to what extent that can be sanded out or not - or whether they will be noticeable. If there is any that bother me enough I can cut some softwood veneer strips & glue them on top & fair it. I'll need to read forum threads on sanding, whether to use something more than just fingers. At 28" I am thinking of a small torture board ... there are sanding blocks where are a foam core, or I could glue sandpaper to something flexible.

     

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    thanks for watching, bye for now

     

    MP

  5. Pete

     

    looking very nice. I am currently doing planks that have quite a lot of twist in them, & seeing your work I was wondering if you put any curve into them before laying them up on the model, or do you just force them into shape? They look like they have at least a 45 twist plus the curve, so it's a good comparison.

     

    Thanks - I'm not really sure what others do, so it will help if I find out what others (that have more experience) do.

     

    thanks

  6. Hello Bob

     

    I look forward to watching this.

     

    Was one of the lines drawings you found by the American shipwright & designer Pete Culler? A friend has done a bit of research on Slocum & believes that Culler's was the closest. Interestingly, this friend also thinks that the design wasn't really a great choice for what he did, being such a shallow shape with no external ballast. But as we know from the text, as a boat she sailed herself very well.

     

    Do you have any reflections on this?

  7. thanks guys

     

    Yes I find the shape interesting too. As far as I can see, not so many countries really developed beamy boats. There will be a lot of examples that I'm not aware of, but when I think of beamy boats it's American & Australian boat types that come to mind in particular. This design isn't massively beamy at 28' x 9'6", but it's no gazelle either.

     

    I like the way this hull shape has a clean water exit aft, but still maintains a lot of bouyancy stability right through to the transom - using the beam to get righting moment rather than by adding more & more lead to the keel. They can be comparatively lightly built & ballasted as a result.

  8. thanks everyone for your interest & comments 

     

    I've started work on the keel. I have some nice old Queensland Maple, which I selected because it planes well (unlike most native timbers) & yet is hard enough to resist most knocks (unlike most native timbers that plane well). This timber was logged almost 70 years ago so it should resist further warping. 

     

    I'm building it up from thick longitudinal laminations. However, I picked up a measurement error so there's going to have to be another 4-5mm lamination in there as well.

     

    The reason for working on it now is that the shape of the keel timber immediately below the garboard is related to the keel shape etc, so roughly shaping it now will help in shaping the lower parts, even though the garboard is done. I'll glue the keel laminations together, shape them & leave it unfixed to the hull until after the planking is completed. Some brass pins will be used to accurately locate the keel, & will also give better purchase for gluing. 

     

    One thing that is really showing is how far aft the centre of lateral resistance is on the hull. I take it that this is because of the power of a gaff mainsail, & the way the long boom usually overhangs the transom so there's quite a bit of push a long way aft. 

     

    thanks, MP

     

    there's another thin lamination required in addition to these

    post-10631-0-98396000-1444772103_thumb.jpg

     

    2 outlined & in position

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  9. A couple of issues with the model had to be sorted & so progress was fairly slow while I was considering them. I've decided to make this a display model only, not a sailing model; also I was finding that after having done about 1/3rd of the planks it was still too flexible to be able to fit ribs into this hull, if I had continued as is. The Huon Pine planking is flexible & the ribs would have to be also v flexible to not distort the planking when fitting them. I did some tests with strips of Spotted Gum & it just was not going to work out, the Gum takes a fair bit to bend & the Pine would have been distorted by that. So, the plywood moulds are staying. Ultimately it is more important to me that the hull shape is accurate to the design rather than just the model looks nice.

     

    So, the hull was slipped off the moulds while it was still possible, the ply cleaned up & the planking was glued to the moulds.

     

    The planking in the stern area will need to be trimmed, the profile has been roughly pencilled on.

     

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    Shown up side down you can see the hull shape somewhat, & you can certainly see that they would make good centreboarders.

     

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    thanks, bye for now

     

    MP

     

     

  10. Hi Mike

     

    nice progress again, she really is starting to look like a yacht rather than a model. Lovely stuff.

     

    There may be no problem with the tacking of the jib around the forestay, if you let the sail blow across the boat as the boat tacks rather than winching the sail across, the sail blowing around will pull the sheets with it. It certainly works for a full sized boat & there's no reason it won't work that way here too. She will be slow to tack as well, which will possibly help.

     

    Mark

  11. Hi Mike,

     

    just a detail on the rigging plan: the sheets of the jib, the outer headsail, need to go around the forestay, which will be at the stem of the boat. They may have a permanent stay at the end of the bowsprit, as this sail would probably be dumped as soon as the weather got difficult, & it certainly would not have had it hanked on to the stay, but I would be pretty sure that they would have had a stay at the stem as a permanent thing so these sheets must go outside the stay.

     

    Just one comment on the issue of extra weight within the hull itself from the RC equipment, it is possible that this boat had some ballast in the hull & not all of it in the keel. It makes a hull roll more kindly, with less whippy action. I have no idea if they did or not, as in this case the ballast would need to be fully secured from coming adrift. So maybe you don't need to be concerned about not have all the weight as low as it can go in the hull. 

     

    hope you don't mind the commentary, best

     

    MP

  12. I've noticed that the planks spread a little away from the moulds, perhaps it's because there's only 3 planks per side on, but I decided to put in at least one full frame & deck beam now as it's going to be easier now than when more planks are on. If that doesn't seem to be enough then I may do more, but we'll see. The frame I chose to make is right at the edge of the raised deck. I cut some 10mm strips of hardwood veneer - Jarrah - & glue laminated them into shape by some judicious clamping & hopeful intentions. The photos show the starboard one clamped & glued in place, & also the port one afterwards, slightly sanded & clamped back in the approximate position. It's still about 8mm wide, which might be reduced, but in any case I never intended the interiors to be accurate to scale & construction so it's ok at that width. 

     

    The veneers were quite easy to get into position, I was unsure of how difficult this would be, but it was quite easy & the resulting frame is good, stiff enough & also springy enough. Because the planking lines at this point of the hull swell outwards by perhaps 0.5mm, & the shape I made with clamps & battens doesn't have any of this swell, I hoped that they would be able to expand a little if I wanted, to suit the actual shape. 

     

    post-10631-0-39222800-1440931588_thumb.jpg

     

    post-10631-0-34178800-1440931610_thumb.jpg

     

    Next is to make the deck beam, some simple knees & then glue it all together.

     

    bye for now

     

    MP

     

  13. Hi David, the stations are about 60mm apart - a little under 2.5" - if this is wide then I didn't realise it in my lack of experience. But I'm confident that I'll work out something if it does become an issue. I can see a couple of possibilities: the planks are about 0.5mm thicker than scale, to allow for some of this; I might be able to work out some sort of jig to hold them in line while the glue hardens ... but I think that the run of planks are quite close to how they would be in reality, & the width is certainly about right at a scaled up width of about 70-75mm maximum.

     

    The timber is very supple, so it will take shapes well without requiring heat - but if heat will help then heat it shall receive.

     

    Any suggestions? 

     

    thanks, MP

  14. Hi there

     

    I finished fairing the moulds & have done a few planks. The intention is to first do a band of planks from the top edge of the transom down, to help stabilise the whole thing. There are some planks above this line due to the raised deck design, . When there's what seems to be a stable band of planks I'll probably start planking back up from the garboard.

     

    They are going on well, I've been using toothpicks at the stem & transom to help hold the planks in position - they will want to pull away under the tension on the planks, but the glue gets slippery & it would be a bummer if a plank slipped & set in the wrong place. The toothpicks act as pegs & hold the planks in place while the glue goes off. 

     

    An interesting scale comparison is a new casting for our boom.

     

    hanks

     

     

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  15. Hi Bob

     

    she is very pretty & really looks just like a dragon: elegant & patrician lines. I read that they were designed to have 2 bunks, I imagine they're pretty tight down below. 

     

    One question: earlier you said " The cross member in the hull is the aft cabin bulkhead support." I don't really know dragons, but that looks like a traveller rail to me, for moving the main sheeting position up or down. Maybe they've put it on top of a bulkhead or something.

     

    Another question - is that 2 pieces of noodle as a working stand? 

     

    ta, Mak

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