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Topic: Iso Development |
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graham_737 |
Posted: 17-Apr-06 18:13 |
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I know it's been discussed time and time again which changes can be made to the iso and that i'm opening up an old can of worms here but having sailed a 400 for the past four days i just couldn't resist raising a few issues about the ISO.
As Topper seems to have completely lost any association with the class and we are making changes that topper don't know about already (Carbon Booms) why don't we start to make changes which are not necessary in order to stay competetive but which do improve the boat;
1. I think the jib on the iso is a big problem as it simply doesn't last long enough! I can't think of one other boat which has a mylar jib which is not self tacking?? (even most of the inernational 14's have dacron jibs!) So why not get a company to make a dacron jib for the iso? If this was battened like the 4000 and 400 then it would have a longer life span and also be cheaper perhaps?
2. The rudder stock could be made a lot lighter and more user friendly, i understand that mike lyons already has a design and supplier if the change was to be accepted?
3. I know it sounds petty and it's been raised before but please... the ISO bubble writing?? again i can't think of any other boat that has the name of the class of boat written in big letters on the side of it?! Any offers?
Anyway, i know these ideas have all been raised before but is there any way that they can be seriously discussed at the nationals and some more changes made as i think it would attract a lot of new people to the class.
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Rob_Heath |
Posted: 17-Apr-06 18:39 |
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Hi Graham,
I agree with you about the jib, we finished one off very shortly after we bought 806 last March, and the 'Best' jib expired at the end of last season. We did manage to buy a very new, second hand jib in the autumn, and it will be interesting to see how the latest Sobstadt offering performs. One of the members of Yorkshire Dales SC runs a sail making and repair business out of his double garage, and has done some good repair work on the genekers for 806 and our Topaz Race X. I asked him if he could replicate the ISO jib in dacron, and he felt that it wouldn't be a problem, and would cost between £120 and £150 - if we manage to destroy the new jib I might pursue this avenue. I don't know how easy it would be to set up a self tacking jib, but if it is feasible, I think it would be a good move - does anyone have any thoughts about this, like how to implement it ?
We don't have any problems with the rudder stock, it might be a bit heavy, but it does seem pretty strong ( and simple - we like simple ! ). People do seem to make a habit of breaking rudder blades though - maybe we aren't trying hard enough !!
On the last point, I like the bubble writing ISO on the side, but there isn't anything stopping you removing it if you don't - or would the class rules forbid the weight reduction !!!
Looking forward to the feedback now the blue touch paper has been re-lit.
Cheers
Rob |
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Ian Moss |
Posted: 17-Apr-06 22:16 |
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Dacron jibs for ISO's, Buzz's and even Bosses have been around for a while. Most sail makers will take a sail and make one based on it. I have seen a few used for club racing and have been know to use one myself (Well Jim's anyway) and can say I havn't really noticed any performance improvement or gain.
Developing a class legal alternative jib would require alot of hard work but is certainly worth looking at it. We would have to be sure people wanted it though as there is no point doing the work only to have members vote against it!
Rudder stocks are unrestricted and if there is an alternative it can be used. Mike has created a rudder stock for the Blaze for which a similar design would work on the ISO but unless he had some firm requests I believe it is not worth his while developing it further, especially as he doesn't sail an ISO at the moment.
As for the logo I don't have a problem with it but I do prefer the purple version to the old pink one which still appears on the Y&Y website.
Ian Moss
ISO 1207
Wet & Windy |
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rob |
Posted: 18-Apr-06 22:53 |
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To all who dont like what they see/sail.
the class association is volentary!
If anybody has ideas they should bring them up at the agm. and offer their time to take the idea further. this would help the class no end.
Ian and the rest of the tech commity have worked long and hard just to make the carbon booms avalible and should be thanked for it.
i think that ian is right about the rudder stocks so if you want a different one go get one.
my apologies for the agression but it's late and i'm fed up of people moaning but not offering to help change things. but hay what do i know.
rob 650 |
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Bob Ladell |
Posted: 19-Apr-06 10:50 |
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Sails - makes me chuckle somewhat. For club racing we've been using an original mylar jib ( 10+ years old pink tabs ) for at least the last 2 years in all weathers, given it all sorts of abuse - including letting it flog ( a real jib killer !! ) - repaired it numerous times and still reckon we get almost as much power out of it as the brand new one. Oh yes and we win / do well regularly leaving L4ks behind pretty easily so it isn't knackered yet.
Dacron has been muttered about several times in the last 4 / 5 years being cheaper to buy but varying opinions as to how long they last. Most views I've seen reckon they last a season, perhaps two and need replacing due to stretch. But alledgedly they are "better" as they are cheaper to replace ...........? Not seen a convincing argument for Dacron - nor heard of anyone doing a comparative 1:1 sail test. Any offers ??
If you happen to have a Sobstad Platinum jib - blue / green tinged rubbery feel to the material of about 4 years ago - they do stretch like crazy and are pretty much a waste of space. Pensioned mine off ages ago. Sobstad have fixed that in the new jibs of the last 2 / 3 years and I haven't found a problem nor heard of anyone complaining about the latest generations. The new ones apparently have a thin Dacron layer on alternate sides to help life.
Rudder stocks - as Ian M says - it's been your choice for the last 2 years+. Read the rules time and you'll see. Your call on what you use. Rudder blades and the odd stock have been broken but as far as Committee enquiries can tell it's been through trying to recover from too much heel by using the rudder - and not crew weight - putting huge loads on both - or hitting the bottom hard.
ISO bubble writing on the side of the hull was an optional extra on new ISOs and cost silly money at the time - £200 I believe. No obligation to keep it. As Rob says - people have whinged about it here several times and then done damn all about designing anything different. Personally I don't have a problem with it and wouldn't pour my money into putting a new design on the boat if one did get accepted - prefer to spend it on event attendance.
I look forward to hearing - and seeing - your proposals at the Nats |
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Rob_Heath |
Posted: 19-Apr-06 13:31 |
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Hi all,
Would anybody be interested in looking at a self tacking jib ?
I am quite tempted to look at this for general club racing / holiday blasting, and would very happy to share experiences via the forum.
In terms of class rules, obviously the track would need to be secured, but if the track was fixed to the space frame I wouldn't be drilling holes in the hull - I might be able to clamp the track rather than bolt it on anyway, but I would have to investigate it further.
Any comments appreciated
Regards
Rob ( 806 )
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Diederik Schuuring |
Posted: 19-Apr-06 15:57 |
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Don't think you could make the current jib self tacking since the foot is too long. So if you would like to try it you would need an other jib with a shorter foot as well. This means losing sail area and speed. Spending a lot of money at an other jib and the hardware to make it self tacking does not make it worthwile for me to look into it. But if you would like to make it work: I'm interested in the results.
Diederik |
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Barry Newport |
Posted: 19-Apr-06 20:58 |
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Self Tacking Jib, what am I going to do up wind! 
Barry 650 (crew) |
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Diederik Schuuring |
Posted: 20-Apr-06 07:43 |
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Enjoy the view, or play with the mainsheet  |
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tasarhans |
Posted: 20-Apr-06 08:31 |
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The tasarclass converted this year from dacron to Mylar.
http://www.tasar.org/index.html
Reasons were costs: Dacron getting more expensive every year (Mylar sails now already being cheaper than the dacron one's) and longevity: Dacron last for one season and after that it loses its shape.
the main difference everybody was talking about was the look: Mylar looks more modern, and provides better sight when racing... One could see boats at leeward.
Against: full battened jib prevents a furler where every one was very fond of (including me)
Speeddifferences where minimal (or due to the larger mylar sails)
It was argued that for real improvement of speef of the tasar one need a complete new rig/ carbon mast preferably with gennaker) All proposals by Frank/Julian Bethwaite (designer of the tasar and the 9ers) on that front where all declined by the class...
What rested was te new sails (like the 29er, but without the cuff)
So I guess Darcron Jib wouldn't help.
I put a furler on the jib to prevent flapping, maybe at the cost of losing the two small battens over time). At the moment we have one jib whiche is rather a virtual one, and a jib which is delaminated at several places. A new one for racing probably without a furler I dont know yet.
Hans |
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tasarhans |
Posted: 20-Apr-06 08:53 |
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Is it a good idea to collect suggested improvements the the ISO or marketing and discuss/ show them in la rochelle?? May be at the bar or a bit more formal I don't know.
For me I have still a lot to learn on the boat but it should be fun to have more of them on the water in Holland or elswhere
Hans |
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John Haslam |
Posted: 20-Apr-06 21:10 |
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Mylar sail's problems have been around for ages i sailed for a good few years on sigma 33's which had sobstad mylars sail's or dacron we had a lot of problem's with the first generation mylar and the same when the platinums sail emerged this was sorted out ion time, the main thing is nobody that raced in the class used dacron sails they were just not quick enough. also what is the advantage of having a self tacking jib on a boat that is not overley difficult to sail.
cheers
John iso911 |
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Bob Ladell |
Posted: 20-Apr-06 23:54 |
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H'mm interesting to see self tacking jib appear. Been thinking about how one might put one on the ISO - without drilling holes or spending a load of money on expensive weight adding tracks.
Reckon it could be done by making off a rope, perhaps a loop, to each shroud bolt then with a couple of rings / knots / bobbles end up with a single jib sheet in the centre of the boat. Jib clew just running from bobble to bobble on each tack. Needs some thought on how you deal with barbers and not at all sure it ends up being satisfactory without relocating cleats .....
Think this is probably a dream on item but ...........
Bob |
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tasarhans |
Posted: 23-Apr-06 20:12 |
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I think a kind of self tacking jib is easy to make when it is allowed to change the jibsheet...
I think when trying to make a laser kind of traveller using the the barberhaulers as the wind and leeward blocks.. just add a block on the jib clew... and ready you are..??
Alternative is a jib sheet just running from barber to barber (both ends in the normal blocks... extra is a a block on the jib clew (running over the new style jibsheet... alle cleats are positioned right and ready...
Not sure about the ability to point... closehauling the jib might be a problem...
Question: is it allowed to add blocks (i think yes, and change sheeting arrangement I don't know)??
Self tacking jib within the rules of non drilling holes.. might be judged as added function?? Though iso is in a bit more liberal regime comparing to the tasar... (all purchase are defined, so are the shrout length etc. ) might be fun to have such a thing as a self tacking jib
[Edited by tasarhans on 23-Apr-06 20:28] |
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Rob_Heath |
Posted: 24-Apr-06 16:16 |
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Hi Hans,
Don't quite follow what you are describing here, is there any chance that you could draw a sketch, scan it and e_mail it to me at
rob@rshservices.plus.com
Many Thanks
Rob Heath
ISO806 |
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tasarhans |
Posted: 24-Apr-06 17:10 |
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I'll try to make it on ISO 788 and take smoe pictures (and tell you how it worked out) I have no scanner up here...
But I'll try to explain a bit more...
My latter idea was as follows:
sheet a line through the jib cleat, through the barberhauler the a new block (Fixed on the jib clew), lead it around the mast, sheet it in the other barberhauler, through the other jib cleat.
The jib (hopefully)may run from one barberhauler to the other when you tack.
Easing the the jib is the same as normal...
I haven't tried it but might work, Main problem might be that it is difficult to sheet it tight to poiint higher..
A tweak might a round going jibsheet (splicing the ends together)
There will be some problems (probably prohibitive) but I'll try it these days...
For my first idea one should take a look at the Laser traveller (at the stern) There is only one line at the centre one should use to ease the jib.
(sorry, unfortunatly I made a new topic, might be deleted..) |
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Rob_Heath |
Posted: 24-Apr-06 19:08 |
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Thanks Hans,
I will have a think about what you describe ( I think I understand now ! )
Cheers
Rob |
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tasarhans |
Posted: 29-Apr-06 17:36 |
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Hi Guys,
I did some experiments with my idea's with the selftacking jib.
I think they failed.
http://members.home.nl/h.smorenburg/iso%20jib/ISO%20ST%20Jib%20hans2.
JPG
http://members.home.nl/h.smorenburg/iso%20jib/ISO%20ST%20Jib%20hans1.
JPG
Main problem (al;ready mentioned bij Diederik) the foot legth is to long for selftacking.
some arguments for this:
I thought about the barberhaulers as an alternative for a regular jibfairlead but it is not. A jib faitlead is the "point of attack" on the boat. In an Iso that point is nearly halfway aft the boat (the jib block and cleat). For good jib sheeting one need a jibfairlead at least in the line of the jibclew and the jibsheetblock halfway aft the boat.
When I made a rope traveller that point of attack is even in front a the space frame... resulting in a very loose foot. To change this one should reshape the jib (kind of high aspect jib like the 29er, tasar etc.) Alternative could be to move the ofrestay more to the front (as with the boss conversion.)Not impossible but too much hassle for now I guess) and we lose the easy hoist on both tacks..
Second problem is the shape of the space frame: near the mast much higher than at the sides.... The rope travelller (nor any other fixed traveller) can't be made flat, resulting in a loose foot of the jib with a huge curve (not tight), not a problem for broad reaching but beating... no go. Playing with the tension of the rope traveller nor the mounted barberhaulers... they worked quite opposite. In my sketches, it lacks of a method of pulling the jibsheet backward, to get it tight enough. one should use a rail or something ...
All other idea's with a traveller mounted on the space frame... I think must be discarded.
I like the idea, thinking it over it seemed easy but in practise... I am affraid it won't work.
Unless the class comes with an updated rig, sailplan, I think it is difficult to implement, but still eager to sea better idea's than mine..
I just found an article on the internet:
http://na.northsails.com/Cruising_Sails/SolutionsSelfTackingJib.htm
Hans
[Edited by tasarhans on 30-Apr-06 20:10]
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