S2 6.7 Junk Rig Conversion

  • 24 Jan 2019 19:46
    Reply # 7127570 on 6872873

    Maybe I am just stalling -- I decided to get some basting tape before I cut up this nice looking yard of Weathermax 65.

    It looks like sailrite.com has at least three different kinds of basting tape.

    For Canvas

    For Canvas and Upholstery

    For Sailmaking and Vinyl

    I think I am using canvas to make a sail. I would not call this Weathermax smooth and flat like Dacron, but it is also not coarse like Sunbrella.

    Does anyone have some advice regarding which basting tape I should use?

    Arne -- I have used staples in the past with good results. This time I am fairly sure I want to use tape.

    Last modified: 24 Jan 2019 19:48 | Anonymous member
  • 11 Jan 2019 15:47
    Reply # 6995398 on 6993814
    Deleted user
    Anonymous wrote:

    Here on my own topic I am still waiting for my yard of Weathermax 65 to arrive and trying to understand exactly how to test for seam pucker. I have thread that was used for modifying a bimini some years ago. It says 'T70' on the sticker which I guess means Tex-70. I think this acceptable for testing.

    Hi Scott-I suspect that WM65 will not pucker as much as WM80, if at all. The weave is very different. See pics. Light blue is WM LT = WM 65. Dark blue is WM 80. It is the prominant horizontal striations in WM 80, if you sew cross-grain, i.e. across the ridges, that you'll get pucker in WM80.
    2 files
    Last modified: 11 Jan 2019 15:57 | Deleted user
  • 10 Jan 2019 18:42
    Reply # 6993814 on 6872873

    Thank you for the response, David.

    My apologies to Jami. It seems I do not understand the etiquette here on the JRA forums. I had considered posting in the 'Vane Gear for Weaverbird' topic. Maybe that would have been more appropriate?

    Here on my own topic I am still waiting for my yard of Weathermax 65 to arrive and trying to understand exactly how to test for seam pucker. I have thread that was used for modifying a bimini some years ago. It says 'T70' on the sticker which I guess means Tex-70. I think this acceptable for testing.

    Last modified: 10 Jan 2019 20:20 | Anonymous member
  • 10 Jan 2019 17:23
    Reply # 6993638 on 6872873
    [moved here so as not to hijack Jami's topic]


    Scott wrote:
    David T wrote:

    Scott,

    [...] Although, to consider the matter in another way, if you were to take my pendulum gear, and instead of mounting the servo carrier on that 45˚ power axis, you were to fix the servo carrier rigidly to the boat - then you would have an aux rudder gear. Not a very powerful one, because it would be small, but it would work for a small boat. [..]

    This was my thought. If the oar in your gear is about half the size of the primary rudder on my boat then I hoped to re-use everything exactly as you made it. The only exception would be eliminating the 45 deg mount and the hinge at this point.

    I also just really like the quadrant and lines directly up to the vane. I did not understand it at first but now I think it is very clever. Pulling the quadrant to the center instead of running lines out to blocks and then back to a tiller seems much more elegant, to me.

    If you were to try this, and needed extra area in the water, I'd make the aux rudder longer rather than wider, so as to give the vane the least extra work to do.


  • 04 Jan 2019 16:06
    Reply # 6983229 on 6979991
    Anonymous wrote:

    Scott

    [ ... ] However, I guess my Plan A would be the hardwood plugs, if I could find some of (nearly) the right size.

    Cheers, Arne

    Thank you for the advice, Arne. I will try for AL alloy tubes and hardwood plugs.

  • 04 Jan 2019 16:05
    Reply # 6983228 on 6979563
    Anonymous wrote:Weathermax 65 looks much more convincing than Odyssey, but again, I suggest that you get a yard of it and do a sewing trial, to see whether it puckers like Weathermax 80, and in which direction.

    I had just convinced myself that spending a significant amount of money on fabric was the right thing to do this week.

    You talked me out of it. I will place a smaller order and do a sewing trial. But -- I need to get started on the real thing some time soon if I ever want to sail under a junk rig.

    Until I get the small test order I guess I will spend some time learning my Weft from my Warp. I am not sure exactly how to determine if a fabric puckers and in which direction.

  • 02 Jan 2019 16:31
    Reply # 6979991 on 6872873
    Anonymous member (Administrator)

    Scott

    That may work, but it surely would be a tight fit. It depends on how you fit the hoops along the luff and leech. Personally I prefer to make the battens a little longer (5-10cm?) than B. I then try my best to tie the after end of the batten flush with the leech, and then just let the forward end protrude from the luff. That makes it easy to tie the sail on and fit batten parrels, HK parrels and the block for the throat hauling parrel, THP (on batten 2).

    The forward end of the battens takes quite light loads. The quickest way of extending the 12’ tubes a bit, is probably to find a round stick of hardwood, say oak or ash, in a store, and then make suitable plugs from it.

    The other method presented itself for me in 2016 as I was making the battens for my Ingeborg: Due to a blunder, I shortened batten 6 instead of the boom. As the photo below shows, I mended it by fitting a splint type joint, using four strips of alloy, plus a number of pop rivets. If you could get an extra stub of that aluminium tube, you could easily add the necessary extra length of tube to each of them. However, I guess my Plan A would be the hardwood plugs, if I could find some of (nearly) the right size.

    Cheers, Arne

     


  • 02 Jan 2019 14:32
    Reply # 6979773 on 6979606
    Anonymous wrote:

    Scott,

    My experience with my barrel-cut sails is that they never take up more length on the battens than the designed length, B. My last sail for my Ingeborg has B=4.90m. [...] the sail now only takes up 4.84m or thereabouts along the battens.

    This seems to be very good news for me. I was assuming that the battens needed to be longer than the designed 'B' on the sail plan for two reasons. The first is that PJR repeatedly stresses using the "fully stretched sail cloth" length. The second is that when I made my little Puddle Duck I cut the battens to be exactly 1.01B as in PJR and I found I needed much longer battens to stretch the sail. I ended up cutting some very long battens just to make it work. This was a flat sail with some very stretchy ripstop nylon for sail cloth.

    With your numbers I get the following:

    ((4.90 - 4.84) / 4.90) = 0.0122  (1.22% Shorter than designed B)

    With B=3700mm on the sailplan you drew for my boat and 12 ft (3657.6mm) battens I get this:

    ((3700 - 3657.6) / 3700) = 0.0115 (1.15% Shorter than designed B)

    This means it should be acceptable to use 12 ft long stock for battens on my B = 3700mm Arne-style sail?

    That would be very good news for my boat budget. I would prefer to use AL alloy for battens. I think I can do this if I buy 12 ft stock and use it directly.

  • 02 Jan 2019 13:42
    Reply # 6979728 on 6979606
    Arne wrote:

    As the photo below shows, Ingeborg’s batten panels certainly take up a double-compound or 3-dimensional shape, so frankly, I fail to understand how those panels can be called ‘2D’.

    Arne


    Let me help you, Arne :-)

    Your panels will lay flat on the floor, either when first made, or when assembled into a sail: = 2D

    (but when the sail has been assembled onto a batten, with the wrinkles, puckering and gathering along the batten taking out some of the excess material, and then filled with wind: = 3D)

    A shelf footed, broadseamed or tucked panel will not lie flat on the floor either when first made, or when assembled into a sail: = 3D

  • 02 Jan 2019 10:50
    Reply # 6979606 on 6872873
    Anonymous member (Administrator)

    Scott,

    My experience with my barrel-cut sails is that they never take up more length on the battens than the designed length, B. My last sail for my Ingeborg has B=4.90m. When fitted to the battens, even with no slack, it only took up 4.87m. After a few test-sails, I eased the tension about 3cm to increase the measured camber from 7% (of the chord) to 8%. In other words, the sail now only takes up 4.84m or thereabouts along the battens.

    As the photo below shows, Ingeborg’s batten panels certainly take up a double-compound or 3-dimensional shape, so frankly, I fail to understand how those panels can be called ‘2D’.

    Arne

     


    Last modified: 02 Jan 2019 10:51 | Anonymous member (Administrator)
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