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Discussion Starter · #1 ·
Hey everyone.
I have a Catalina 25 with a roller furling, with a 150 genoa.

I also have the "sliding blocks"? Which is a pulley on a rail on both sides of the boat.

I had light winds today and figured what the heck.
I moved the blocks up alot further than normal ( probably 3 feet closer to the front of the boat and it created a pocket instead of a taunt front sail.

So here is a noobie question....
Where should my "blocks" actually go? Does it depend on the wind?
Should it be closer to the mast? Or closer to the winches near the back of the boat?

Thanks for the clarification.
 

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Hmm. I don't think the video answered my question...
The jib car position:

Rough guidelines:

  • the leech and foot of the foresail should be about the same shape.
  • the sheet should point to the mid point of the luff of the sail.

As you bear away from a close -hauled point of sail the car should be moved forward.

Fine tuning using tell-tales

Jib leads can be located by observing which portion of the sail begins to luff first.
  • Luffing in the upper portion means that the lead should be moved forward. Too much twist.
  • Luffing in the lower portion requires the lead point to be moved aft. Too little twist.

Does this help?

Jack
 

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Hi

Check the headsail basics video it has genoa traveler location. traveler forward reduces twist by moving clew forward, traveler back increases twist (neutral is determined by drawing a line from half way up sail luff to the track).

Generally you want to flatten your foresail at the front of the sail when the wind builds with backstay tension. You also want to increase twist on the foresail when the wind builds therefore traveller back in higher wind! (this is the basic rule for traveler location.)

There is a lot more in the video about headsail control. Check that one and if you still have questions fire away!
 

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As a very simple guideline, when going close hauled and you sheet in the jib so it is 1" from the chain plate the sail should be 2" from the spreader tip.

Moving the car forward will cause the top of the sail to come in towards the centerline of the boat and the spreader tip. Moving the car aft will cause the top of the sail to fall away from the centerline of the boat and the spreader tip.

So, when sailing close hauled with the jib sheeted in so it is 1" from the chain plate look up to see how far the sail is from the spreader tip. If it's more than 2" from the spreader tip move the car forward. If it's touching or less than 2" from the spreader tip move the car aft.
 

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First, a little common terminology: Your "sliding blocks" are known as "fair leads" or "jib cars" (west coast and east coast folks tend to use different nomenclature). The track is either a "fair lead track" or a "jib track". Whereas the general principals apply to all boats, what specifically works on my boat may not work exactly the same on yours, so you will have to work it out on your boat. We call this "dialing in" the boat and once we get the optimum setting, we either mark it down on the track or make note of it somewhere.

<O:p</O:pI'm assuming that your C25 only has one fairlead track on each side of the boat? Your initial setting will be when sighting up the jib sheet, your LOS will be exactly halfway up the luff of the sail. Move your fairlead up or down until this imaginary line is halfway up the sail's luff. Your 150 will have a different position on the track than say, your 110 lapper jib. Now for the fine tuning: while sailing, move the fair lead up or down the track so all tell tails are streaming aft. Then, slowly luff your boat into the wind and watch your genoa tell tails. If the upper one breaks first, move the fair lead forward. If the bottom breaks first, move the lead aft. You want all the tell tails to break at the same time. This "fine tuning" adjusts for wind speeds.

<O:p</O:pOther adjustments: Moving the fair lead forward closes the leach and moving it back opens it up. If the winds are building, you can move the fair lead way back (opens the leech) and this will help in controlling heel. Moving the fair lead forward will "power up" the boat and give you better acceleration (but the downside is you will experience greater heel). If you have two tracks on each side, use the inner one in lighter winds. Move to the outboard track if the winds are building and you see compression on the mainsail (a "bubble" depressing the luff area). If you are using the outboard track, you will not point as high into the wind. We tend to go to the outboard track only in very windy conditions and when we are on a reaching leg.

<O:p</O:pUlta light air sailing is an art form and it is easier to show you on the water than writing about it. Generally, you will not be able to point as high and you will need to move your mainsheet traveler up to compensate. Both jib and mainsheets will be fairly taught as is your halyards and outhaul. Think of slow moving air molecules as being lazy and you need a smooth sail with a flat camber to keep them attached as they slide along the sail.<O:p</O:p
 

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Discussion Starter · #11 ·
First off.. WOW.
Thanks for the indepth explanation.

I do have 2 'blocks' on each side. One is very large and one is very small.
I have only used the larger ones. I have contemplating using the small ones to backfeed my boom when running downwind ( which I havent tried yet ).

So I need to move my 'blocks' up to be in the middle of the front sail?
I did this on Saturday in very light winds, and had my front sail with a big 'pocket'. it was so far out, my girlfriend ( who knows less than me said.. is that a spinnker sail? ). I said no, but it was so far out, I could see how she thought it was.

I am going to look online for some diagrams to "dialing' it in.

I do agree it is much easier to be "showed" instead of "telling".

Thanks for the help.

I am just tired of being on the boat, feeling the wind, and boats are blowing by me, and me not knowing what I can adjust to 'maximize' the given wind.
( this happened all day saturday ).
 

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I'm assuming that both blocks are on the same track and the larger one is in the front? That one is called the fairlead and that is the one you move around to make all of your adjustments. The smaller one to the rear of the track is to provide a fair lead into the winch on the cockpit coaming. And you position this one so you don't get sheet overrides on the winch. It never moves after that and plays no role in sail trim.

Are you able to trim your genoa so that all tell tails are streaming straight back? I suspect that you might have moved the fairlead so far forward that it wasn't doing its job at all and you didn't have enough tension in the genoa sheet to trim the sail. You can move the fairlead too far forward or too far aft. If you are new to sailing, move the fairlead so the sheet evenly bisects the luff and use your sheet to get the tell tails streaming (you are actually changing the sail's angle of attack). Master this, and you will be equal to half the sailors out there. Then move on to the fine tuning aspects trim.

<O:p</O:pA 150 genoa overlaps the main by a considerable amount and if you are not trimming just right, it will also disrupt the airflow over the mainsail as well. Your 110 lapper jib is a much easier sail to trim and learn on. You may want to practice on that one even though it is slower in low winds than being frustrated with the 150 (because it is much more sensitive to trim). A lot of trimming is done in inches or fractions of inches. And remember, it takes lots and lots of practice to master the nuances of trimming so go out there and sail!<O:p</O:p
 
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