Measuring junk sailing performance

  • 05 Jul 2017 19:15
    Reply # 4934208 on 4913961

    For boat on boat tests there is one design that stands out for a number of reasons.

    1. Small enough for the rigs to be fairly easily made at a reasonable cost.

    2. High enough ballast ratio not to be overly effected by crew weight and placement.

    3. Sea kindly enough to accept the full range of weather conditions.

    4. Less effected than most by short nasty sea states.

    5. Reasonable sized rudder for good control.

    The only problem is that it is a popular racing boat so fleets tend to be fairly highly tuned so not ideal for comparison with a cruising junk rig.

    Oh, I forgot to mention the name of the design. The humble FolkBoat. Perhaps it could called something like Jester?

    Just a thought, Slieve.


  • 05 Jul 2017 18:02
    Reply # 4934038 on 4933908
    Webmaster JRA wrote:

    Nothing to disagree with there.

    If we want a boat that is common among members as a target test boat how the Schooner-rigged Benford 34 Dory might be a good bet.

    Chris


    1) expense and labour. A suit of sails this big is not to be undertaken lightly.

    2) unsuitable for testing all the different types - low AR, high AR, split, etc.

    3) it seems as though there are many Benford Dories, but I venture a guess that there are many more Kingfishers and New bridge Boats.

  • 05 Jul 2017 16:56
    Reply # 4933910 on 4913961

    No Alan, it is not aimed specifically at you, but it is on record that JRA funds have been paid on a couple of occasions for commercial work done in the past without the elected officers being informed, and that there was no return for the membership. I am now also aware that during the period I was working as R & D Secretary at my own expense, even to the extent to buying a new computer to enable me to do the work, that significant regular payments were being paid out of the Association's funds to a commercially interested member for the work I was doing without members or elected committee members like myself being informed.

    I do not want to see the funds donated to the JRA being used other than as intended by the donors. I accept that the members need someone to provide services they are not able or prepared to do themselves, but I am not happy to be asked for help, which I freely give only to discover later that it is due to the inability of those making profit from my work to understand what they are doing, and without them informing me.

    There should be clear proof that that the membership would gain before funds are handed out, and having seen some experienced junk rig sailors needing help to get the best out of the split rig on Poppy I wonder who could or would perform the necessarily lengthy and boring repetitive tests required to achieve a meaning-full result. As said, only boat on boat tests in reasonable sized boats will remove the uncertainty of wind/ sea state variations as demonstrated by the Americas Cup contestants, and that requires a huge commitment.

    Cheers, Slieve.


  • 05 Jul 2017 16:54
    Reply # 4933908 on 4913961
    Anonymous

    Nothing to disagree with there.

    If we want a boat that is common among members as a target test boat how the Schooner-rigged Benford 34 Dory might be a good bet.

    Chris


    Last modified: 05 Jul 2017 16:54 | Anonymous
  • 05 Jul 2017 16:01
    Reply # 4933840 on 4913961
    Anonymous

    Let me share my experience of two boat testing with you. When we were developing the SwingWing rig, we used Lasers as our test boats because Robin and I both had one already. Our objective was to see if the SwingWing was better to windward than the standard junk, and to see if there were any problems with the SwingWing that needed t be ironed out before we committed to a full size rig.

    As we both raced our Lasers at Hamble River SC we had a fairly good idea of our relative helming performance, and so we swapped boats frequently to cancel that variable out. We proved to our satisfaction that the windward performance was better, regardless of helmsman, and learned that if there was any gap in the front of the SwingWing sail the whole thing would blow up like a balloon, which was only fast backwards. We also learned about sticky hinges (we were using varnished wood battens in a varnished ply socket). I think we lined them with formica.

    They did the job for us, at the cost of only making the miniature SwingWing, but we still have no objective data about the performance of either rig.

    I would advocate Lasers as test boats because they are to be found all over the world, are all pretty much the same, and have an unstayed mast so all you have to make is the experimental sail. However, they are quite tippy, so you need to be willing to get wet.

    Nowadays, being older and wiser, but less fit and less keen to get wet, I would prefer to use a displacement boat as David suggests, but the problem then is finding a matched pair in several locations around the world where junkies might want to try out new rig variations. I think it is logistically impractical. What is the most widespread keelboat? HUnter Sonata, perhaps? Folkboat? I don't know.

    If we go the instrument route the logistics become much easier, and we get some hard data at the end as well. 'Nuff said?

  • 05 Jul 2017 15:31
    Reply # 4933606 on 4930176
    Slieve McGalliard wrote:

    Well done Amiina! Well done Edward and Steve!

    I've posted this on the 'Measuring Junk Sailing Performance' thread (and perhaps it should be copied into the racing thread), simply because it shows what some members are doing, and have been doing without sponsorship or help from the Association. All the useful development work and rig improvements have been done by members who give so freely of their time and effort, and at their own expense. I believe it would be wrong for the Association to sponsor test equipment to assist those who have made financial gain from their involvement with the JRA when the average member stands to gain very little if anything for the expenditure.

    If anyone wants test equipment then they can either make it cheaply or buy it out of their own pockets, as the rig developers have done.

    Cheers, Slieve.

    Setting aside the ill-advised and unwarranted comment on potential financial gain, there is still this point to be made.

    I'm a rig developer. Like Arne, anyone who wants to make use of anything I develop is welcome to do so (whether or not a commercial product is planned). Unlike Slieve and Edward, it is completely immaterial to me whether I can beat another boat by 37 seconds after a 10 hour race, as I'm not developing with a view to racing success, but with the aim of achieving rigs which are good in all departments, of which speed to windward is just one. Of equal importance to a cruiser are such items as perfect control when sailing through a tight, winding, rock-infested passage, as I did this morning; and absence of flogging, chafe, fatigue and the like, during a long passage.

    I don't need instruments for the kind of sailing that I'm doing. Should I, then, have to go and buy them, so that I can pass on to other interested parties performance data for my rigs (and any other rigs which would fit on my boat)? I don't think so. If the JRA will fund an agreed package of instruments, and a protocol can be agreed on how the testing is to be done (by me and by others), then I will attempt to make some useful data available.

    There are now 700+ members in the JRA. Can we not find the resources to advance on two fronts: data logging on a suitable boat, and match racing in two or more suitable boats? 

    I say yes to the former, and also yes to the latter, but is 12ft big enough? 

    Half a century ago, I raced a National 12ft dinghy, with a measured sail area of 90sq ft (I think it was). This was a handful, although admittedly, the rig was tall.

    I would say that the boat should sail in displacement mode, not planing mode, to reduce the influence of the weight and skill of the sailor, and further, that it should be under-canvassed. If a "good" rig and a "bad" rig will both power the boat at hull speed, then nothing will be learned.

    Yet 10 sq m is a good size for the sail. Smaller, and more demands for accuracy of cutting and sewing are placed on the sail maker; larger, and costs start to rise

    So how about a boat design at about 15ft, to fit within the length of two sheets of plywood, and with water ballast and a non-planing design? And I might just throw in at this point the possibility of a "Siblimette" at that size. If we're making junk rigs, why wouldn't we put them on junks???

    Last modified: 05 Jul 2017 16:19 | Anonymous member
  • 05 Jul 2017 10:45
    Reply # 4933363 on 4933021
    Anonymous member (Administrator)
    Graham Cox wrote:
    Alan, I am sure that, like myself, the majority of the members of the JRA do not believe you have a mercenary interest in promoting junk rig.  Both you and Robin Blain have made significant contributions both to the JRA and to the development of junk rig design, and you have freely shared your knowledge with other members.  The fact that you also offer your services commercially to those who do not have the means or desire to build their own rigs is perfectly acceptable.  You have to make a living!  And for those who need assistance, your services are invaluable.  Thank you for your contributions to the JRA, and I hope you are not discouraged by misguided attitudes from continuing to do so.  I can assure you that this unfortunate attitude is not that of most members.

    Graham, thanks for your well-considered words.

    Although I very often share view with my friend Slieve, I feel little reason for blaming the JR pros in England. In this case, I just happen to think that match racing on identical hulls is a better way to find the best speed performance of rigs.

    When I started telling about my new rigs and findings in the early nineties (‘cutting and trying’), Robin Blain made me feel very welcome in JRA, and I never felt that he or others of the pros were ‘stealing’ my stuff. Quite the contrary; I would have liked them to do that as I felt that the JR development was slow in Britain. Being strictly an amateur, I regard all I write to JRA about my rigs to be free and public stuff, which anyone can discard or make use of (small elements of it or the whole package), either as amateurs or commercially. Be my guest.

    Btw, off the record; when I looked up that Item 10d from the AGM, I also spotted the next item, 10E:

    e) Linda Crew-Gee asked if the JRA could approach Arne Kverneland with a view of assisting him financially or otherwise to complete his book on the Cambered Panel Junk Rig.  Annie Hill said that this had already been done and that Arne is happy with the incomplete book on the JRA website along with his other resources so that he can continually update the material as developments occur.  All members at the meeting agreed that a huge vote of thanks should be paid to Arne for all the help he provides to members.

    Annie is right. I hope to add a bit here and there, and even write up a Chapter 7 one day. Don’t worry about me, folks. I feel I have received bags of cred for my write-ups during all these years.

    Arne



    Last modified: 05 Jul 2017 15:33 | Anonymous member (Administrator)
  • 05 Jul 2017 02:56
    Reply # 4933021 on 4932491
    Alan Boswell wrote:
    Slieve McGalliard wrote:

    I believe it would be wrong for the Association to sponsor test equipment to assist those who have made financial gain from their involvement with the JRA when the average member stands to gain very little if anything for the expenditure.


    Oh dear! I do believe this must be aimed at me. What a shame that Slieve seems to think I am making this proposal for some commercial gain.

    Commercially, I do not care a jot if the JRA pursues this project or not. It will make absolutely no difference to me commercially and will not assist me in any way that I can currently anticipate in my (rather tiny) business designing junk rigs for customers converting bermudan rigged boats. It might well help my customers in the choices they make, but that is a benefit to them, not to me, and incidentally nearly all of them are members of the JRA, and if they are not I encourage them to join.

    Equally, I do not have a boat or a radical rig to test, so the Association having some test equipment will be of no assistance to me in that direction.

    As a founder member of the JRA and past Chairman I take exception to the implication that my only interest in it is commercial. I have done my share of carrying the load for no reward and paid my subs for 37 years.

    I have passed a proposal, as openly discussed on this forum, to the Chairman and Hon Sec and it is up to them and the committee to decide whether "the average member stands to gain very little if anything for the expenditure".

    My interest in this project is purely the pursuit of knowledge that it seems to me would be useful to the members, and that is currently unavailable. It is curiosity not profit that is driving the proposal.

    While I am at it, I want to loudly praise all those who have come up with ideas for developing and improving the junk rig, and have spent time, money, and effort working on them, and shared their experiences and results. I salute and admire them all. I have done my share of that too! I just wish we had more solid and comparable performance data for them.

    In my humble opinion, the JRA should have an interest in developing the rig, but it should be as an impartial observer, a recorder of facts, and a depository of knowledge for the benefit of its members who can all access it. By and large, it is doing this. Whether or not the members choose to access the knowledge is entirely up to them.


    Alan, I am sure that, like myself, the majority of the members of the JRA do not believe you have a mercenary interest in promoting junk rig.  Both you and Robin Blain have made significant contributions both to the JRA and to the development of junk rig design, and you have freely shared your knowledge with other members.  The fact that you also offer your services commercially to those who do not have the means or desire to build their own rigs is perfectly acceptable.  You have to make a living!  And for those who need assistance, your services are invaluable.  Thank you for your contributions to the JRA, and I hope you are not discouraged by misguided attitudes from continuing to do so.  I can assure you that this unfortunate attitude is not that of most members.
  • 04 Jul 2017 23:38
    Reply # 4932940 on 4913961
    Anonymous member (Administrator)

    (... all criticism should be constructive  -  so I suggest...)

     

    I decided to go back to Alan Boswell’s initial posting here. He refers to Minutes of the AGM 2017, Item 10d.

    Only now did I look it up. It says:

    “ Pete Hill would like the Committee to set up a technical sub-committee to investigate the performance of all the various rigs that are being developed.  The Chairmen asked if Pete would volunteer to head the group and he replied that he would be happy to do so.  He said it might be necessary to have models or a small boat fleet of identical boats to test the rigs under all conditions.  Pete thought that there would be a high degree of interest in the study results.!

    Pete’s idea clearly goes along the match-racing line. There is no mentioning of fitting an instrument package. I am more with Pete in his way of thinking, here.

    Challenge number one is to find the right test boat, big enough to carry a real sail, big enough to be easily-handled by people over 60years or over 90kg. (Laser and Topper is too small). My dinghy Broremann had a sail area of 10sqm. This sail handled like any junk sail. I therefore suggest that 10sqm should be the standard area (profile sail area, not counting any slots or splits). I have found a boat type which I think would suit the task: The PD Goose. This is a stretched version of the 8 x 4’ Puddle Duck Racer, PDR, being 12 x 4’. There are some good clips of it on YouTube. These boats would be quite quick and easy to build, and even ‘mass-produce’ in 2-4 numbers.

    The other challenge is to find a little dedicated group of people who would build, keep and maintain 2-4 such boats and do the testing (before taking over the boats). It seems to me that the NZ junkies are the most likely to take such a challenge, but anyone could do it anywhere. I might be able to produce a Johanna-style sail of 10sqm for one of the test boats.

    Arne

    PS: A goose site worth checking.

     


    Last modified: 05 Jul 2017 09:24 | Anonymous member (Administrator)
  • 04 Jul 2017 15:21
    Reply # 4932491 on 4930176
    Anonymous
    Slieve McGalliard wrote:

    I believe it would be wrong for the Association to sponsor test equipment to assist those who have made financial gain from their involvement with the JRA when the average member stands to gain very little if anything for the expenditure.


    Oh dear! I do believe this must be aimed at me. What a shame that Slieve seems to think I am making this proposal for some commercial gain.

    Commercially, I do not care a jot if the JRA pursues this project or not. It will make absolutely no difference to me commercially and will not assist me in any way that I can currently anticipate in my (rather tiny) business designing junk rigs for customers converting bermudan rigged boats. It might well help my customers in the choices they make, but that is a benefit to them, not to me, and incidentally nearly all of them are members of the JRA, and if they are not I encourage them to join.

    Equally, I do not have a boat or a radical rig to test, so the Association having some test equipment will be of no assistance to me in that direction.

    As a founder member of the JRA and past Chairman I take exception to the implication that my only interest in it is commercial. I have done my share of carrying the load for no reward and paid my subs for 37 years.

    I have passed a proposal, as openly discussed on this forum, to the Chairman and Hon Sec and it is up to them and the committee to decide whether "the average member stands to gain very little if anything for the expenditure".

    My interest in this project is purely the pursuit of knowledge that it seems to me would be useful to the members, and that is currently unavailable. It is curiosity not profit that is driving the proposal.

    While I am at it, I want to loudly praise all those who have come up with ideas for developing and improving the junk rig, and have spent time, money, and effort working on them, and shared their experiences and results. I salute and admire them all. I have done my share of that too! I just wish we had more solid and comparable performance data for them.

    In my humble opinion, the JRA should have an interest in developing the rig, but it should be as an impartial observer, a recorder of facts, and a depository of knowledge for the benefit of its members who can all access it. By and large, it is doing this. Whether or not the members choose to access the knowledge is entirely up to them.

       " ...there is nothing - absolutely nothing - half so much worth doing as simply messing about in junk-rigged boats" 
                                                               - the Chinese Water Rat

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