Okay here’s my question. Does it help to have the jib twist be adjustable on a CR-914? what I mean by that is if I could move the jib boom fore and aft a tiny bit, or make adjustments to the jib booms position fore and aft, would I gain any advantage? There would be more twist I think if the boom went aft etc, know what I mean? I’ve found that the back stay tension has no effect on jib twist. It’s a separate issue from jib slot which I can already adjust. I’ve noticed big changes in boat speed with small changes in jib slot but I was wondering if jib twist is a factor as well in how the main and jib inter-act aerodynamically?
Yes true but if put loop at head of the jib so it hold the topping lift line away from the spreaders (line follows the leech) should minimise it getting caught in the spreaders.
However, when you get big gust the jib boom will still lift and the topping line could still catch the spreaders, to stop completely this put rubber line from end of the Jib boom and attached to the topping lift about 5-6 cms up with tension on it, and as the boom lifts (loosening the topping lift line) the rubber line takes up the slack and you will never have topping lift line caught in the spreaders again.
Most of the top boats I see around Europe use this …
Yeah, the US and Canada’s largest AMYA sanctioned class, is pretty funny…
I guess a fairly simple build, and simple rig, simple rules and cheap price is a hard combo to beat.
in a one design class, like the soling, addition of a jib topping lift is just an arms races type of thing. if allowed, everyone does it, and all boats are the same again, so no real benefit for any one boat. Plus, from a beginners standpoint, one less thing to worry about adjusting…With a soling, if you get beat, you are getting beat by a better skipper, not someone who has the latest and greatest go fast stuff…
daves a great skipper and great guy lots of good info…
The Soling 1meter, and the CR-914 are probably the two strictest one-design classes in AMYA.
So, theoretically in both of these classes the only thing that makes someone win is the skipper.
The only real differences between the two classes are:
Class population (S1M is higher) and sailing properties (make your own decisions)
Personally, I don’t sail in either class.
Not as an elitist thing. But rather, I just don’t have any interest in the S1M or the CR-914.
I’ve never sailed the 914, but I can imagine that it sails a lot like the Victoria. nice thing about a large class, is more regatta options for traveling,. which is why I like the Ec12 and Victoria as well…tons of activity and since they aren’t developmental, you aren’t chasing the latest and greatest. it all comes down to thumb time…
I’d put the seawind and laser also near the “top rung” of the strict one design fleet. which is good an bad. good in that, its a level playing field, bad in that, if the manufacturer ever goes under, the class is dead…
Yeah the soling is a bathtub with a keel…but if you are all sailing the same bathtub its all good.
But yeah if they allowed a topping lift on the soling…I’d have one…if they allowed panels sails, spars other than wood… I’d have them as well…But thats another topic…
Agree it depends on your perspective, everyone’s different but To me the Soling is the best there is hands down in terms of performance in a range of conditions, while not really excellent in any particular condition. Its also a pretty boat, looks like a yacht, I digress…
My original question had more to do with the inter-action between main and jib and if there is a proven advantage to controlling jib twist in a purely aerodynamic sense? factoring in jib slot and all the other variables? anyway, I sort-of suspect there isn’t much advantage, but I’m not really a scientist I’m just curious.
it is an advantage, provided you keep the topping lift from fouling on the spreaders. One fouled topping lift and cost you a race…
the fact that you can tune your jib(wing) shape and not have to play with the rig tension, or mast bend, ect is HUGE…
with the soling, you have to play with your forestay/backstay tension to get the jib to twist off. if you have a topping lift, you can snug everything up and then dial in your topping lift. much easier to tune, IMO and it gives you a more precise setting
To get back to the question
Jib twist AND main sail twist has everything to do with how the boat moves or doesn’t move on any given day’s conditions.
Generally light air days the sails are fuller, rounder and more open.
Heavy air you want to pull the outhauls vang on and everything else to flatten the sails.
You can trim harder and point higher when the wind is up.
Light air days pointing is pretty much out the window, sail low and fast.
This is where the topping lift comes in as most useful to add shape to the Jib.
When it’s blowing the wind will shape the jib and the topping lift is not really used. (If everything else is right)
You ask about moving the jib boom fore and aft. I don’t see this changing the twist at all.
It would have more affect on the helm because it would change the center of effort more than anything.
This year I’m wanting to learn more about fine tuning sails.
Have read Bob Sterne “How to sail Faster” which is [u]full of good detail [/u] and he talks lot about using tell-tales as major element in fine tuning sails.
My question is: What is the best location for tell-tales on sails, right on luff/leech/center of each panel or other ?
It never ceases to amaze me how few r/c yachts I see fitted with tell tales when they are such a fundamental part of good sail trim. I can’t imagine their placement would or should be any different to those placed on full size yachts, thus;
For a headsail, somewhere between the luff and point of maximum draft, usually a set of 3 parallel with the luff at 25%, 50% & 75% of height on both sides.
For a mainsail, they’re attached to the leach usually around the end of the batten pockets.
Although only on full size yachts, in the past I’ve sailed with some incredibly talented skippers & trimmers etc, both amateur and professional, and without exception they’ve all used tell tales as an indicator of finer sail trim.
Best of luck with the learning curve - it’ll certainly pay dividends. I assume this is all about lifting the silverware in Italy this September…?!!
Happy new year,
Regards,
Row
Edit: A fairly basic article but well worth reading for an introduction is -
while sailing you should need a FPV-equipment to watch the tell-tales;
from the shore it looks like this.
(you’ll have to zoom in with 200% to see the tell-tales at the spots at the sail’s luff and leech of main and jib).
You’ll need some material, which is flexible enough to fall and rise and which won’t start to drill behind the leech or won’t be sticking at the sails luff all the time.
To be honest I haven’t found the right stuff yet. :x
The leech tell-tales helped me a bit for the setup at the shore before the run.
I should have chosen thicker tell-tales, but this would have disturbed the scale look.
But now I don’t need them anymore.
It’s now more to intimidate the newbies
Thanks Wolfgang, nice looking sails …make them yourself ? Claudio tool ? you’re fox intimidating newbies excuse my ignorance here but what is FPV equipment !?
Hi Row, I’ve tried tell-tales on RC boat before and was frustrated with the constant changing of wind direction on the small lake I was sailing on, long ago (lot of trees at lakes edge) & came to conclusion unlike independent sail trimming “hands on” with big boats … is not the same as on RC boats using only one servo for both sails, need to come to shore-line to adjust settings.
Will take on board your advice placing tell-tales…thanks
Now I have larger lake with more constant wind direction, I’m hoping to learn fine trimming of Jib/Main to find ideal settings, once found, I figured on taking notes of settings and then doing away with tell-tales.
My quest for lifting Italian Silverware is always my goal, may need to consider spending more time sailing with my adversaries, rather than alone :rolleyes:
Hi Alan,
these sails I made with some kind of one-half-claudio’s-gadget better known as austrian ‘gurkenzange’.
This tool might be better for ‘fast sails’ (flat sails) but I always had trouble to set the draft position.
FPV - first person view - sometimes I’m thinking about tearing apart those new drones with video equipment…
you would have a better look at the tell tales
Hi Wolfgang, interesting gadget, I’ll will give it try …thanks.
FPV hmmm …you’re right, one of the many challenges of trying to see tell-tales on RC sailing boat, I try (but rarely successful) taking lots of high res photo’s.
Now thinking of using tell-tales with boat set-up on swiveling stand (on shore) as first step, then take it from there on the water for finer tuning.
I did miss the wind shift and was way to deep. Waving upward and forward the tell-tales at the shrouds show the turbulences as if they where attached at the sails. Couldn’t believe it!
Yes, with the tell-tales at the shrouds it’s kind of a raw or basic information. But it would be an overkill to watch two sets of tell-tales at jib and main while trying to control this little
beast in the next gusts and windshifts.
Initially I took the tell-tales on my cat to show the apparent wind at a reaching (on my cat I try to have them parallel to the main boom after a gybe).
My original question had more to do with the inter-action between main and jib and if there is a proven advantage to controlling jib twist in a purely aerodynamic sense?
I learned the topping lift line is the easiest way to control the jib twist. And most needed in drifting conditions!
I tune the jib twist with the topping lift to the wind conditions and after that on the water I set the jib slot as needed (with the third servo).
Depending on the back stay tension the jib’s outhaul may rise in gusts and will allow more jib twist, but back in light winds you will have the desired jib twist.
And as seen in Alan’s picture with the rubber line attached to the topping lift line you don’t mess with the spreaders.
Some months ago on my older long keeler I moved the jib pivot from 14 to 25%. With the 14% jib pivot I needed way too much backstay tension to keep the jib outhaul down in gusts.
The high backstay tension gave you a nice forestay tension esp. while beating, but I ran into structural problems with the hull (jib attachement to the bow and hull bending).
With the 25% pivot you need much less backstay tension and you get less stress in the bow section of the hull.
But the other point is you have less forestay tension an therefore more sag in the jib’s luff (so I already made flatter jibs).
Jib twist control without a topping lift is really tricky, but not impossible.
Infinity 54 class sectretary Jim Hensel is always at the head of the fleet:
Still sailing without topping lift: #80: Jim Hensel’s Infinity 54 at SFMYC’s regattas at SPRECKELS LAKE
