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Freedom 40 Cat Ketch Junk Rig Conversion

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  • 03 Nov 2013 16:09
    Quote
    Reply # 1426900 on 1425484
    Anonymous member
    David Tyler wrote:
    Use a very simple text editor to compose text. Word and other full-featured WP put in a lot of hidden formatting, which these fora don't like. The blue background can happen if you have some text highlighted.

    I second this. You can also use Ctrl-Shift-V (instead of the usual Ctrl-V) with Google Chrome (I don't know whether it works in other browsers) to paste as plaintext, without any formatting.
  • 03 Nov 2013 05:26
    Quote
    Reply # 1426783 on 1424184
    Anonymous member
    Welcome aboard Erik and Evi.  I'm sure you are already more than pleased that you asked for a few ideas and suggestions.  The JRA is a fabulous resource simply and entirely because we have some fabulous members whose knowledge is only matched by their generosity in sharing it.

    I am completely convinced that you are going in the right direction to change your rig from a Freedom cat to a junk schooner.  The comment I hear time and again from those who have converted to junk rig is 'why don't more people do this?'  Ease of handling and reduced stress lead to increased enjoyment, which, at the end of the day, is what it's all meant to be about.  I am sure that you will not only enjoy the end result of your conversion, but you will find the process of designing your rig and making your own sails interesting and satisfying.  And that first sail after doing all that work yourself is unforgettable!

    Good luck with the project and keep us posted: I love following the stories of these transformations!
  • 31 Oct 2013 18:37
    Quote
    Reply # 1425579 on 1424184
    Deleted user
    Hi Erik and Evi

    Not a lot of time at the moment to respond in detail so will just throw in a few thoughts here and dig oout our Freedom 39 Pilothouse Schooner sailplan (before and after) so I remember to keep my promise to you ton get it scanned and uploaded to the site :-)

    I dislike the look of the 'Chinese Finger Trap' rig (congrats on mastering out albums, by the way) as much as I did our original Freedom rig, even though our F sails were in tracks rather than wishbones - an 'improvement' that many F owners seem to have made. Though I've no experience of F wishbones, people I've met with them in our often inclement weather usually wish they'd got rid, because of the difficulty of reefing wet sails. Reefing our massively roached sails running in tracks with 3 in-boom reefing lines was not easy either. We were very glad to raise and use our junk sails, though we re still shaking out bugs.

    Working through your (blue) notes/questions:

    Some general outline of what I think we want to do or have for a JR conversion, in some order of importance:
    1. Keep it simple
    2. Don't move or cut masts 
    3. Increase sail area
    4. Minimize number of control lines and fixed lines
    5. Single sheets
    6. Minimize Dmin
    7. Minimize sheet purchase (we have good winches)
    8. Move CE slightly forward
    9. Be asthetically pleasing
    1. Agree
    2. We were advised by Alan Boswell who drew the rig (6 panels on each sail) that we could     lose 8 feet of the foremast and 15 feet of the main (both carbon). Members' suggestions were not to do that with any urgency and we haven't seen any need: extra work, the boat can obviously take those lengths, and there is some feeling that reducing mast height could be detrimental - so we will suck it and see.
    3. Agree. Areas were and are (final design by Chris Scanes)
    Freedom Main    Freedom Fore     Total      Fore as % of main
    503 sq ft           301 sq ft            804       37%
    Boswell Main      Boswell Fore
    554                  242                   796       30%
    We contracted Chris Scanes to make the sails and he, like we, felt we could take the J areas above the F areas. We did it by adding a panel to the main, giving:
    Main                 Fore
    577                  290                   867       33.5%
    I wish we'd added a 7th panel to the foresail though we haven't felt the need for it yet. Sail material is in hand should we need/want to. Generally we find the boat sails brilliantly with only 4 panels of each sail: it's a good, fast hull (Ron Holland).
    4. Yes, that's what junk is all about :-) We currently have on each sail: halyard, yard hauling parrel, two luff huuling parrels, batten, yard and boom parrels. Did no sailing this year for medical reasons but will be experimenting with Arne's and Paul Fay's ideas next season.
    5. We have single sheets on each sail. Double would negate item 4! We have 5 part on the main and 3 part on the foresail. Each starts at the top of the mast.
    7. The boat came with one big electric winch that services both sails from the cockpit. We retained the sail travellers but have taken them out of use by tying the sliders off slightly to port, though may centralise them next season. Cambered panels (made separately, slide into tracks on the alloy battens) have plenty of drive so we don't miss the extra complexity.
    8. Why do that? If there's a balance problem just reef one panel of the main. If we'd added that seventh panel to the foresail we could have retained the relative fore/aft sail areas.
    9. Yes, though one man's pleasure is another man's niggle.

    Sails should be:
    • identical for and aft
    Well you can aim at that but keep CE in mind.
    • with camber, method open
    Though our sailing experience with camber is only 3 seasons and in low wind speeds compared to 30+ years with flat in various, I'd agree with that so far. (Consider separate panels.)
    • larger than the original 780 sq ft - above 1000  sq. ft preferred
    Yes, as above.
    • HM style or fantail (the latter being a very pretty shape, but darn if I've been able to make it fit)
    As David said, you're unlikely to be able to get a fantail shape between schooner masts. You need plenty of room for the sheets, unless you go for double.

    Re sheets, they're going to be long anyway - it's the nature of the beast. You get used to them, or strangled (consider a hoop to keep them above head height.

    David's 2-section sheet sounds interesting so may try that in due course. There's always something to experiment with and you don't need to get everything right first time - unlike with most other rigs.

    Hope that helps. Just some quick thoughts really. Now back to the day job...

    PS Re text editing - I've put some notes in our Help page (menu on left), though David explained it all well as ever :-)
    Last modified: 31 Oct 2013 19:10 | Deleted user
  • 31 Oct 2013 17:01
    Quote
    Reply # 1425484 on 1425464
    Anonymous member
    Erik and Evi Menzel Ivey wrote:David and Arne - thanks for your quick replies and input.  

    David - Thanks for the pointer to the two articles written by Paul.  There is a lot of relevance since the boat are similar sized.
    • Undercut Arne style boom
    I haven't got on so well with this. It means that the topping lifts can't be so near to the leech, and this is a contributory factor to the flapping of the leech when reefed that I've experienced. 

     Some questions to help educate me:  

    We have two size 46 two speed Andersen winches that seem to manage the current sails (390 sq ft) just fine using a 3 part sheet.  And it is the last couple of feet of trim that are the hardest/highest load, when the leach gets tensioned. Would the loads on the JR be different.  I know the sail area will be increasing 20-40%, but the leach is much more controlled using the multi-sheetlets, thus maybe less load. Somewhat mute since I have yet to figured out how to rig a 3 part sheet on the JR given our Dmin restrictions.  5 part works better in that regard.

    I have two 30:1 two speed ARCO self-tailers (very good). The greatest load is on the halyard, yet with 3:1 halyard, I use only the 14:1 speed to hoist the last two panels of my 630 sq ft sail. I use 30:1 if I am shaking out a reef with the sail full of wind. The halyard load is greater than the sheet load. On my 3:1 sheet, I use the 14:1 speed, and very rarely use the 30:1 speed, when it;'s blowing very hard and I'm working from the pramhood and have less purchase on the winch handle. Your 46:1 winches will cope easily with both halyard and sheet.

    Sail balance - I'm in the 10% range in order to keep the current CE moved slightly forward.  Is that sufficient to minimize issue with the yard ending up on the wrong side of the mast during reefing?  Mast interference with the sail shape/air flow.  What are some good guides.

    For beating to windward, less balance area is better. 10% will be fine for a schooner. 

    Yard lenght and angle  I'm around 70 degrees angle, but play with the length  - besides that a longer yard increase the sail area in the top panels, other considerations?  How about the leach angle of the top panel.

    A high peaked yard is more efficient, but risks getting behind the topping lifts when deeply reefed. Stay with 70 degrees for your first junk rig. A shorter yard risks getting behind both lifts as well. Some people add a light extension to one or both ends of it, beyond where the sail is attached, to make this less likely. I prefer to put two unsheeted battens into the top of a HM sail, to decrease the length of leech here - there is less loose cloth to drape down when the sail is furled.

    Boom angle - David, you did a table of theoretical boom angles to help cambered sails stack better.  Is you thinking still the same?  For the range of numbers I'm playing with, I'm at 11.5 to 12 degrees.  Cutting the boom short helps, too.

    Paul Fay made some sails using these angles, and told me that the principle worked out perfectly. I wouldn't shorten the boom.

    Luff round - the fantail design has luff round.  Would some on a HM sail plan help in avoiding the diagonal creases.  I would think that some luff round would "push" the battens aft if there is luff tension.

    I'm not sure about this. The luff round goes along with fanning the battens, and I haven't yet been able to design a schooner sail with fanned battens that works out.

    Grrrrr.... off to work.  Sorry if this isn't proof read too well.  Is there a way to save drafts or is composing in Word or some other editor the option?  Also, I seem to get blue background in some of my text - anybody know why?

    Use a very simple text editor to compose text. Word and other full-featured WP put in a lot of hidden formatting, which these fora don't like. The blue background can happen if you have some text highlighted.

    Erik
  • 31 Oct 2013 16:53
    Quote
    Reply # 1425482 on 1424184
    Anonymous member (Administrator)

    Erik,

    You hardly have space for luff round. My solution has been peak up the yard properly, as shown under my little wite-up "Peaking up the Junk Sail" found under "my" folder:

    http://www.junkrigassociation.org/arne

    With the position of the yard sorted out, the parallelogram-panel sail below it will behave quite well. Much the same as on Ti Gitu, I guess.

    Storing a draft: I often draft my postings here in Word first. To make the text edible to this page, I have to store it in rich text format, then copy and paste the converted text into this page.

    Cheers, Arne.

    Last modified: 26 Aug 2017 12:46 | Anonymous member (Administrator)
  • 31 Oct 2013 16:22
    Quote
    Reply # 1425464 on 1424184
    Deleted user
    David and Arne - thanks for your quick replies and input.  

    David - Thanks for the pointer to the two articles written by Paul.  There is a lot of relevance since the boat are similar sized.

    • Sail Area - he's at 1000 sq ft about the same as what I am shooting for.  
    • TG's hull may be stiffer, likely higher displacement.  
    • I'm not so sure about the ballast on the Freedom 40 - around 6000 lbs gets mentioned. Not clear how much of that is in the centerboard, which is not light and takes the draft from 4.5 to 9 ft. TG is suppose to be 8000lbs.  I'm going to say TG is stiffer.
    • Masts - He's about 4 ft shorter on the unsupported section. Diameters are the same, his are steel, ours are Al.  I'm guessing TG's is stiffer and likely heavier  
    • Boom, battens, and yards within the range of what I've come up with.
    • Diameter and wall thickness seem a bit larger than other I've read about, but for long distance cruising, possibly that makes sense.
    • Undercut Arne style boom
    • He's gone down the same road as others with HM cambered sails by eliminating or reducing the loads on the HKPs by "encouraging" the sail into the right position with a THP and YHP (hope I'm getting the acronyms all right).  In any case, I can see that sorting out the control lines may be an issue.
       Split sheets - I think that is a good option for a single-sail boat and definitely would increase twist control.  As it is  (and would be hard to change), our mizzen gets trimmed at the forward edge of the poop deck, right aft of the steering station.  The main sheet lead to the aft edge of the cabin top.  A walk from the wheel if one is single handing.  In any case, four lines instead of two, and far appart - and since we are Bay sailing for a bit, sail trim is more often.  

    Arne - The top of the mast is whippy and whereas I'm not super concerned about it breaking, it may affect the way the sails function.  I like your idea of a clamp-on halyard attachment.  I think there is enough taper that if it is designed properly, it should not slip downward.  At present we actually have a spectra noose about 1 ft below the mast crane to help guide the halyard and keep the head of the sail close to the mast when fully hoisted. Maybe even something like that would work - the top of the mast would still be loaded, but it would not see much of a horizontal force.  In any case, an easy experiment.

     Sheet angle - at 17 ft boom/battens I'm per the PJR midrange on the main and at a more shallow angle on the mizzen.  Is that reasonable?  16ft battens/booms start dropping the sail area below the 1000sq ft level, but "improve" the angles even more.

     Sheet tracks, aka traveler:  Would work on the main but not the mizzen if lead to the boomkin.  Seems reasonable to try if a central attachment point doesn't work.  I have sailed with travellers on BR and don't mind using them. Certainly help control leach loads.

    "tie the battens flush to the leach"  - I'm still trying to figure out how long the battens should be  :), never mind how to build the sail.  I do have two sewing machines - a Pfaff 138 to cover the zig-zag, and a Juki 563 (walking foot) for an serious straight stitching.

     Some questions to help educate me:  

    We have two size 46 two speed Andersen winches that seem to manage the current sails (390 sq ft) just fine using a 3 part sheet.  And it is the last couple of feet of trim that are the hardest/highest load, when the leach gets tensioned. Would the loads on the JR be different.  I know the sail area will be increasing 20-40%, but the leach is much more controlled using the multi-sheetlets, thus maybe less load. Somewhat mute since I have yet to figured out how to rig a 3 part sheet on the JR given our Dmin restrictions.  5 part works better in that regard.

    Sail balance - I'm in the 10% range in order to keep the current CE moved slightly forward.  Is that sufficient to minimize issue with the yard ending up on the wrong side of the mast during reefing?  Mast interference with the sail shape/air flow.  What are some good guides.

    Yard lenght and angle  I'm around 70 degrees angle, but play with the length  - besides that a longer yard increase the sail area in the top panels, other considerations?  How about the leach angle of the top panel.

    Boom angle - David, you did a table of theoretical boom angles to help cambered sails stack better.  Is you thinking still the same?  For the range of numbers I'm playing with, I'm at 11.5 to 12 degrees.  Cutting the boom short helps, too.

    Luff round - the fantail design has luff round.  Would some on a HM sail plan help in avoiding the diagonal creases.  I would think that some luff round would "push" the battens aft if there is luff tension.

    Grrrrr.... off to work.  Sorry if this isn't proof read too well.  Is there a way to save drafts or is composing in Word or some other editor the option?  Also, I seem to get blue background in some of my text - anybody know why?

    Erik
  • 30 Oct 2013 23:14
    Quote
    Reply # 1424980 on 1424184
    Anonymous member (Administrator)

    Stavanger Wednesday

    Hi Erik.

    Your suggested rig plan looks reasonable. There are two things I would have focused on, if that project belonged to me ( remember, this is a serious project):

     

     

    Halyard:

    It is most likely that you will not need as tall masts with JR as with the original rig. On the other hand, I would not “burn the bridges” and chop off the surplus top sections or drill any holes in them (yet). However, suspending the junksails from the original mast tops will put too much load on the flimsy top section. Instead, I would (on each mast) construct a mast clamp, which I would clamp lightly to the mast in the “JR mast position”, a bit below the top of the yard. This clamp would be fitted with the needed brackets to take the halyard, lazyjacks, mastlift and spare halyard. To keep it from sliding down the mast, one or two suspender lines would be tied between the mast top and this clamp. This will offload the top-section of the mast, compared to your sketch.

     

     

    Sheets

    Getting the sheets right on a JR schooner is not easy. We tend to use up the space between the masts. On your drawing it doesn’t look bad. After what I have experienced with my friend’s 49’ Samson. I am inclined to try an old Sunbird trick; using sheet tracks. I would fit serious sheet tracks (Strong steel tubes?), going from rail to rail, with powerful control of the sheet track runners, brought back to the cockpit (4 in all). I think these are the best way to avoid too steep sheets with resulting high forces, as seen on some schooners.

    To spell it slowly; when sailing close-hauled on sb tack, the runners would be hauled up to the sb rail. As I fall off, I would not touch the sheet, but just ease the runner control until, finally, the runner is all the way down at the lee rail. Then, and only then would I ease the sheet to square out the sail. I would do this to both sails.

    This makes for a bit more working lines when tacking. Still, if you have to do some short tacking, maybe you could try to keep the runners locked in the middle and keep the sheets a bit slack. This gives a bit lower pointing, but as soon as you are out in free water, you can start playing the runners again for best sail set and pointing angle.

     

     

    Whatever you do, tie the battens flush with the leech to avoid catching the sheets.

     

     

    Good luck!

    Arne

    Last modified: 30 Oct 2013 23:21 | Anonymous member (Administrator)
  • 30 Oct 2013 22:07
    Quote
    Reply # 1424925 on 1424184
    Anonymous member
    Hi Erik,
    and welcome to the JRA! Let's see what we can do to assist you.

    First, the Fantail sailplan only works on single masted rigs, so we can discount that. There isn't enough room to put it onto a two masted rig, unless the boat is very long and narrow. [but it would be perfect on a small Wylie :-)  ]

    Second, the example that springs immediately to mind of a 40ft boat with two equal sails of 500 sq ft each is Paul Fay's Ti Gitu, and there are articles in magazines issues 58 and 60. Those sails are maybe of higher aspect ratio than the ones that you've drawn, and since you have some excess mast length, it would be tempting to go for higher aspect ratio for Raven.

    I think you'll need 5:1 sheets to handle this much sail; though you may want to consider doing as I do, and splitting the sheets into an upper sheet of 3:1, with a self tailing winch to give enough power, and a lower sheet of 2:1 which can be hand-hauled. For a large, high aspect ratio sail, this would give much better control over twist when deeply reefed.
  • 30 Oct 2013 00:07
    Quote
    Message # 1424184
    Deleted user
    A warm hello there to all you friendly folks at JRA.  I've lurked for more than a year and we joined several months ago.  Got a warm welcome from Linda and Brian and have been exchanging private e-mail with several members.  All the different discussion threads have re-enforced what a great knowledgeable and supportive group this is, and we are happy to be part of it.  This posting is a bit length - my apologies in advance.

    Background and introduction:  I've been sailing since my early teens (more than 30 years ago), both in Germany and the US, and since moving to the San Francisco Bay area in 1988 have enjoyed sailing and racing on the Bay.  My better and much more charming partner Evi is learning to sail and work on boats with enthusiasm.  We currently own two boats - a small 24ft sliver of fiberglass called a Wylie Wabbit 24 that we've been racing for 10 years (wyliewabbit.org if you want to see that fun) and a new-to-us a whole-lot-more-fiberglass center cockpit Freedom 40 cat ketch Raven that we seem to work on a lot and sail less.  (hopefully I figured out how to link properly to the pictures... else maybe the webmaster can help)

    So Raven is the subject of this topic....  the aluminum masts and wooden wishbone booms are original, but the sails were changed back in '94 from wrap-around to a lace on design that is similar to a Chinese finger trap.  This set up  works, but is awkward to reef.  One has to lower the boom, drop the sail some, disconnect the lacing,  then raise the boom again, then haul in the aft end of the sail... and I am sure I am forgetting a step or two.  It definitely requires leaving the cockpit and working at the ends of the boat.  Plus the sails are 19 years old.  Dacron sails lasts forever, but that does not apply to them keeping their shape.  Planing for new sails is in order.

    A back of the envelope estimate of new wishbone style sails, sail track, full batten mains, possible new booms, comes in at $12 - $20k.  And some of the issues, such as  ease of reefing, change but do not go away.  I've sailed a lot on the Wylie Cat 30 design and my current thinking is that the wishbone rig is great for day-sailing, but less good for long distance cruising.

    So JR sails are a possible alternative.  A copy of PJR has been by my bedside and desk, I've read and re-read many of the threads and articles here and on the Yahoo group site, stared a pictures and drawing, with the gracious permission from Barry Stellrecht to use his Excel spreadsheets that he programmed to design his Freedom 33 Flutterby's JR sails,  I have at this point enough knowledge to be dangerous and thus I am reaching out for much needed help and advice!

    Some data on the Freedom 40:
    • LOD 40ft
    • LWL 35ft
    • Beam 12 ft on deck,
    • Displacement estimates range from 20,000 to 28,000 lbs the latter hopefully being fullyl oaded.
    • Sail area currently 390 sq. ft each sail, 780 total
    • Draft centerboard up/down 4.5ft/9ft
    Some general outline of what I think we want to do or have for a JR conversion, in some order of importance:
    1. Keep it simple
    2. Don't move or cut masts 
    3. Increase sail area
    4. Minimize number of control lines and fixed lines
    5. Single sheets
    6. Minimize Dmin
    7. Minimize sheet purchase (we have good winches)
    8. Move CE slightly forward
    9. Be asthetically pleasing
    Sails should be:
    • identical for and aft
    • with camber, method open
    • larger than the original 780 sq ft - above 1000  sq. ft preferred
    • HM style or fantail (the latter being a very pretty shape, but darn if I've been able to make it fit)
    Barry's Excel file is great in that it allows to easily change many features and see the effects.  In playing with the boom/batten/yard size, luff and leach length, boom angle, sail balance, etc,  it seem like the following picture  emerges...


    Seven pannels 
    Boom/batten/yard length from 16 to 17.5 ft
    Panel height from 3.5-4.5ft
    Aspect ratio around 2.10 to 2.4
    Yard angle 60-70 deg

    One of the largest issues has been trying to minimize Dmin and the amount of sheet purchase.  In the original thread on Flutterby, Kurt U. presented his solution, which elegantly changed the panel height from bottom to top.  It did create the need for a 5 part sheet.  Our sheet is 3 part and it seems long.  IN any case, I keep hitting my head on this.

    OK, sorry to be so long winded in my first post. Looking for any and all input and help, and there are plenty of additional questions on my end.

    Erik

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