Lets start a new topic…and see what you all think about it[;)]
I am preparing my new baby…
So, I have a channel for the rudder and one for the sails…IF a third channel would be used…where and why would you most likely use it? jib, backstay…anything?any comments?
Personaly, I am thinking to control the jib…but is it really helpful???
Waiting for the pros [:)]
Wis
_/ if it isn’t broken, don’t fix it! _
My vote is for Jib Trim. I installed it this year on my EC12, and really like it. Allows for fine tuning the slot without bringing her to shore, and very helpful in pinching marks.
Hi Wis -
If a multihull, I would use to handle jib - allowing the jib to be held to windward during a tack and backwinding the jib would help push bows over (especially on a cat configuration). For a monohull, many use the third channel for backstay and mainsail power/depower.
You might want to include what class boat… a jib trim is not only a good idea on an EC-12, but also the only one allowable by class rule. Depending on the boat… it makes a difference, but just my two cents worth I would go for backstay. It help downwind performance a great deal… and it is one of the easier to install (Which always helps)
First; well as I mostly sail alone; I dont really bother about “classes”.
Second; the boat is called MicroMagic; and its a fast growing class in the Netherlands and Germany…
some urls for you guys:
http://www.micromagic.nl/foto.htm (check the vids…53cm and pure power)…site in Dutch
http://www.micromagic-rc-segeln.de/ (in German…check the gallery…VERY intersting
Thx
Wis
_/ if it isn’t broken, don’t fix it! _
Backstay, which really controls jib shape, is the most useful single function third channel. On the German Skapel, one channel changes backstay, jibtrim and main and jib outhauls.
Hi Roy,
How are all four items done? Can you explain or send a sketch?
Carl Bihlmeyer
J120mm
Wis,
Have you sailed any full size boats? What control function do you use most on full size boats?
My experience is that you use some sort of mainsheet fine tune or main traveller the most. Why? As a boat heels the balance changes which causes it to develop helm. Fighting helm with rudder is slow! So, on most full size boats that I have sailed, the main trimmer spends a lot of his time playing either the mainsheet or the traveler to keep the helm under control.
Now, you can do this with jib fine tune as well. Essentially, you ease both sails and then trim the jib back in with the fine tune. But, why not cut out the middle man of having to move both sticks and just have the 3rd channel be either a main fine tune or main traveller? That would be my first choice for a 3rd channel.
I have managed to accomplish this with only 2 channels as I have discussed at length in the past. so maybe you do not need to waste a 3rd channel to do this.
So, my second choice for the 3rd channel would be a jib twitcher. I really hate having to do those annoying “S” turns to get my jib to wing out. Especially if I am on a broad reach instead of dead down wind. So a jib twitcher would really be a bonus in getting the jib to wing out and get that extra speed that comes from extra sail area down wind.
Will Gorgen
Hi Will,
Any new, up to date ideas on setting up a jib twitcher?
Carl Bihlmeyer
J120mm
Hey Carl,
I worked with Phil Sarelis on his latest design. What we came up with was to put a long double arm on the servo and a short double arm on the jib club at (or near) the pivot. Then you attach a line from each end of the servo arm to the matching end of the jib boom arm. The two lines would have enough slack in them to allow the jib to wing out to either side when the servo was in the neutral position. The long arm on the servo would allow you to pull in all that slack and then pull the jib into a wing position when the servo was turned to full travel on one side or the other. You could even hold the jib in the wing position by holding the servo at full travel.
It is a pretty simple concept, but if you’d like me to put some diagrams together, let me know…
Will Gorgen
Will,
That would be great. Sounds simple enough and fool proof. E-mail is: cbihlmey@comcast.net.
E-mail me for phone number.
THANKS.
Carl Bihlmeyer
J120mm
My vote would be jib trim because you can run a tail off the backstay and control that. The back stay can be tightened by running a tail off the mainsheet to the backstay so that you can have it set at a light or median position for normal sailing then if you crank the main with the trim you can get anywhere from a quarter to a half inch extra on the backstay. The major backstay tension is controlled with a bowsie. Run a piece of line off the main sheet through a block to the main backstay system which will tighten only when trimmed really hard. I would use a strong hitec or rmg winch the futaba 5801 will probably blow if you use it to do this. The backstay will also properly control the jib twist if you go without a jackline and use the pivot jib offset to control jib twist. It sounds a lot more complicated than it really is but it works well on my US1M and am thinking about it for my M. You essentially get it all without adding an additional servo. Jib slot remains the same but set it up with a fair amount of twist which is essentially the same as an open slot then when you crank the the main the backstay tightens from the tail_flattening the main and pulling on the headstay which will force the aft of the jib boom down . The jib leach can be controlled by putting a small jib rack at the pivot point on the boom. moving the jib pivot fore and aft on the boom will allow you to control the initial jib twist. There is a pretty good sailor on my home pond who uses a system like this very successfully. Sounds worse to do than it really is. I would use the third channel on a motor to win those light air races.
I would retract my hydrofoils or raise my spinaker with the extra channel
“Expertice is gained trough mistakes. However repeating
same mistake is not learning but stupidity.”
I might have not enough space to put a spinaker [:)] and for foils…that would be even harder.
Lets be serious…backstay or jib…hmmm I might try the jib.
Wis
_/ if it isn’t broken, don’t fix it! _
Looking at the pics alot of them are painted up VOR 60 or Open 60 style. How about water ballast?!
Luff 'em & leave 'em.
Wis
I think - from reading these posts- that I would use an arm winch and Will’s jib trim method (which I am going to do on my next boat) and use the 3rd channel for backstay. Why waste a channel on something you can accomplish with the two you already have. Oh, Roy, I would like to hear more about the multiple use of one channel as per the Skapel. Do you have a link that might show it? If there is a good way of doing multiple tasks you could use the 3rd channel to open beer.
Thanks
Don
Vancouver Island
Hey Wis,
I took a look at the boat on the links you provided and here are my impressions…
The aspect ratio on the sail plan seems fairly low and the boat seems pretty beamy. This will give it more docile helm characteristics. The lower rig CE and higher prismatic will mean the boat will be less prone to heel. And it will also mean that the boat will have less of a tendancy to develop adverse helm when it heels.
So, you probably will not have a lot of balance shift issues with the boat (compared to some of the tall rig boats out there). I would try sailing it first to see what you like and what you don’t like about the boat.
The other thing is that the boat is pretty small - about the size of a Victoria or a little smaller. This will make it difficult to add a lot of tricky bits to the boat. There is just not a lot of room available. The boat will likely seem a bit jumpy and twitchy given its smaller size so you may find that it is nearly impossible to assess when to make a tuning change like adding backstay tension or adjusting the jib slot. Anyway, I doubt you will get a lot of satisfaction out of a jib slot or backstay adjustment channel on a boat this small.
So if you want a 3rd channel, I think you will be happiest with a jib twitcher.
But you may want to think a little more about whether you want the 3rd channel at all…
Take a look at how cramped this boat is inside: http://home.arcor.de/kat.dreyer/boot/grpklar01g.jpg
I don’t like how this rigged the sail servo at all. I think that is the standard arrangement. He will have very little chance of fine tuning the sails when the arm is in the close hauled position. The arm is at its maximum gain position at close hauled so a small amount of Tx stick movement is going to result in a large change in the sheeting. This is exactly the opposite of what you want. At close hauled you want good fine tune control. Secondly, you will need a vang better than what this guy has done.
Here’s a guy with the right idea: http://home.arcor.de/kat.dreyer/boot/no_secret_g.jpg . Note the nice compression vang. I would have lowered the sail a little more, but that’s a good start. He also has a little better sail servo arrangement but still not great. If he put the sail servo in front of the rudder servo (so that both were in line on the boat centerline) then he would have enough room to have the sail servo pointed more directly away from the sheet turning blocks so that he could get good fine tune control at close hauled. You would need the sail servo to be higher than the rudder servo so that the arm would pass over the rudder linkage. Notice how he moved his Rx and batteries forward to compensate for moving the servo weight aft? That is a good idea…
It looks like the keel strut is going to be in the way for any good sheeting arrangements from the standard servo position. You might do well if you mount the sail servo just in front of the mast (with the arm poiinted straight forward at close hauled. If you want to use the standard position, then maybe a drum would be better…
But no matter what you do with the sail servo there is not a lot of room in there for another servo. Maybe you could put the twitcher right in front of the mast…
Good luck with this one… you may want to look at some of the newer smaller micro servos out there for the rudder and your 3rd channel. It will save some room and weight.
Will Gorgen
Will,
First, thanks for taking time to check the urls.
I am willing to use some micro mini servos or whatever, to save some weight (place). But after thinking more than usual (lol)…maybe its not really worth the troubles. Its a really small boat 53cm…but one thing is sure…it does sail VERY good for its size!
Again thanks for the ideas…time to rethink the whole thing…i like the idea of the rudder servo…
Wis
_/ if it isn’t broken, don’t fix it! _
