J/30 Class Association

Pinching or Backwinding the Main

Posted By: Fitjarald

Pinching or Backwinding the Main - 07/13/17 04:16 AM

Hi everyone!

I am completely new to sailing as of 2 summers ago, with this being my first summer racing, so my apologies if this is a very newby question.

I have been relying on more experienced crew to tune in the 150 genoa we race with, and we generally tighten the sheet until the main just starts to backwind. However, this leaves the jib a couple feet out from the shrouds, and if I go by the telltales, I don't point nearly as high into the wind as other boats in our local fleet - and we're the only J/30! And the only fractional rig! Shouldn't I be just destroying them all!?!? If I point at the same angle as them, I'm pinching and loosing speed.

In the hopes of destroying them all, I'm wondering how close to the shrouds I should bring the 150 in 12-15 knots of wind, and what I should do about back winding the main? We tried a bit more outhaul tonight, which worked a bit, but it hurts to finish side by side with a CS30, knowing with the handicap you should have finished miles ahead... frown

Thanks for any and all advice that may be offered!
Posted By: Rhapsody #348

Re: Pinching or Backwinding the Main - 07/13/17 11:51 AM

The jib should be sheeted in. If you don't have telltales on the luff, install them about 3" in from the head stay at 3 places equidistant along the leading edge on port and starboard sides. Additionally put telltales on the leech of the jib similarly spaced. When sheeting in the jib, make sure you adjust the jib car so you get good telltale flow along the leech top and bottom. Don't worry about the bubble in the main just yet.

The luff telltales you find work best in light air when both are streaming aft. In the 12-15 kt range the inner (winward) luff telltales should be streaming upward about 45 degrees. As the wind is up, you'll want to make sure the headstay is tensioned to move the draft forward and reduce headstay sag. It also helps to put on backstay.

For the main, make sure you hoist the halyard all the way and can use the cunningham to tighten the luff, moving the draft forward in heavier breeze. Outhaul will also be on more in heavier breeze. Ideally the main and jib leech profiles will be matched, but if you are overpowered, you may have a "speed bubble" in the luff of the main. You can tighten the main sheet and take the extra out of the vang and play the traveler in the puffs. Another method for big air is to vang sheet - pull, in main tight, put on vang hard, the set the traveller somewhere below centerline and play the mainsheet in the puffs. The vang should keep the leech tension when you ease the main in the puffs.

All this assumes you have set the mast base and rig using the tuning guides - available on the menu under Info, Articles of Interest, J/30 Rig Tuning. Good luck!
Posted By: Fitjarald

Re: Pinching or Backwinding the Main - 07/13/17 04:17 PM

Great! Thanks very much for this. So if I'm understanding, in lighter air, reduce jib halyard tension lightly to increase the sag in the headstay, coming on a bit harder as the wind builds to decrease sag and start to flatten the sail. Sheet in close to the shrouds, and don't worry too much about backwinding the main. Apply a bit of cunningham to tighten the luff of the main. At what point is the slot between main and jib too small, where we would be sacrificing too much speed for pointing ability? The main gets real weird looking with the 150 sheeted in as close as possible, which is why we were leaving it out further, but sacrificing quite a few degrees in pointing.

For the telltales on the leech of the jib, if they are not streaming up top, I would move the jib car forward, correct? Any tricks for moving the jib car under load? Our last race was lighter air, so I had a dedicated crew member take a seat on the sheet while we adjusted the car. Otherwise, would I just luff up while we adjust it quickly? We've been playing with the lazy side while on the other tack to try to get it positioned, but the more I read, the more I realize that this is a key point of continual adjustment throughout the race, especially as uphaul and backstay tensions change.

Our more successful races were sailed in 25+ knots of wind, with just the blade jib on, and I got a good feel for her under this sail plan and in the heavier air, but our usual is 12-15knots through the rest of the summer, and I've dropped from 3 or 4th in our class, to dead last the past two races.

EDIT: Yes, I set up the shroud tension and mast position based on the rig tuning guide at the start of the season.
Posted By: Rhapsody #348

Re: Pinching or Backwinding the Main - 07/13/17 07:26 PM

Originally Posted by Fitjarald
Great! Thanks very much for this. So if I'm understanding, in lighter air, reduce jib halyard tension lightly to increase the sag in the headstay, coming on a bit harder as the wind builds to decrease sag and start to flatten the sail.

That is correct

Originally Posted by Fitjarald
Sheet in close to the shrouds, and don't worry too much about backwinding the main. Apply a bit of cunningham to tighten the luff of the main.

That is correct - you'll need to start depowering the main (make it flatter and draft forward). Another strategy is to get twist on the main (traveler up, loose leech). Usually better when you need to power through chop.

Originally Posted by Fitjarald
At what point is the slot between main and jib too small, where we would be sacrificing too much speed for pointing ability? The main gets real weird looking with the 150 sheeted in as close as possible, which is why we were leaving it out further, but sacrificing quite a few degrees in pointing.
The best way to do this is get another boat to tune with you and try different settings to maximize your VMG. Even though the boat may be slower, you may actually be doing better closure rate to the windward mark.

Originally Posted by Fitjarald
For the telltales on the leech of the jib, if they are not streaming up top, I would move the jib car forward, correct?
Correct

Originally Posted by Fitjarald
Any tricks for moving the jib car under load? Our last race was lighter air, so I had a dedicated crew member take a seat on the sheet while we adjusted the car. Otherwise, would I just luff up while we adjust it quickly? We've been playing with the lazy side while on the other tack to try to get it positioned, but the more I read, the more I realize that this is a key point of continual adjustment throughout the race, especially as uphaul and backstay tensions change.

On a J/30 you really cant adjust real easy under load. You should mark the track with numbers the same on each side so you may reproduce the settings easily. I used a Brother label maker. Much better than counting screw holes.

Originally Posted by Fitjarald
Our more successful races were sailed in 25+ knots of wind, with just the blade jib on, and I got a good feel for her under this sail plan and in the heavier air, but our usual is 12-15knots through the rest of the summer, and I've dropped from 3 or 4th in our class, to dead last the past two races.
The blade is your friend when the wind is up and you will point significantly better using it in those conditions.

Posted By: Fitjarald

Re: Pinching or Backwinding the Main - 07/17/17 04:01 PM

Thanks for the help! Had our womans cup race on Saturday, which gave me time off from the helm to play with sail trim, and applied these new suggestions for an easy second place finish! Had another J30 owner out last night for trim and spinnaker training - I've had a 150 on for all the races, but may drop down to a smaller sail to reduce heel, as we're usually light on crew, and he noted we had excessive heel last night with only 15kts of breeze or so.

First time with the spinnaker up! Awesome - trying our first race this Wednesday.

We have a couple questions from Spinnaker set up - he has a downhaul attached right at the mast, where as we have a foreguy much closer to the bow. We were trying to decide pro's and con's of this. Should I put another loop closer to the mast, as it makes spinnaker trim easier (wouldn't have to adjust the downhaul everytime the guy is adjusted). Secondly, we use a roller furling, as it makes sailing with the 1 year old MUCH easier! Any suggestion on where to keep the spinnaker halyard, as it got twisted on the roller furling our first attempt.
Posted By: Rhapsody #348

Re: Pinching or Backwinding the Main - 07/17/17 04:13 PM

Glad to hear that the tips are working! Attaching the foreguy near the base of the mast means there is one less line to adjust when you need to rotate the pole fore and aft. I made that modification when I had Rhapsody and it was much better. Also consider mounting spinnaker twing padeyes about 3 inches behind and 1 inch outboard of the shrouds on port & stbd. In this position, unless the wind is really up, you don't need to use the foreguy. Read this old thread.
Posted By: Steve Buzbee

Re: Pinching or Backwinding the Main - 07/17/17 05:34 PM

To add some thoughts about upwind settings/rig tune:

-Rig tune is not a "set it and forget it" proposition. I use different settings for about every 3 knots of difference in breeze. Make sure in 12-15 you are at about 39/39 or slightly less on the Loos gauge-it will make a huge difference in your ability to flatten the main. If you are light on crew, go slightly tighter to keep the boat on its feet.

-Outhaul should be pretty tight in most conditions. I only ease it substantially in very light or very choppy conditions. If the outhaul is too loose, you will definitely bubble the main when the jib is properly trimmed.

-we carry the class 163 genoa and trim it to about 2" off the shrouds/spreaders and don't have any issues with backwinding the main. Make sure your traveler is on centerline and the mainsheet is very tight (especially above 12 knots of breeze)-your top leech telltale on the main should be stalled about half the time.

My basic advice is to trim the jib tightly to maximize point and then play with all the adjustments on on the main to get it driving properly. NEVER sail below your highest point as indicated by the jib luff telltales-you are sailing an enormous amount of extra distance if you sail too low. I usually try to get my windward jib telltales to "bounce" a bit (i.e. stall just slightly) once the boat is up to full speed.
Posted By: Fitjarald

Re: Pinching or Backwinding the Main - 07/17/17 06:04 PM

Originally Posted by Rhapsody #348
In this position, unless the wind is really up, you don't need to use the foreguy.


Forgive me if my terminology is a bit limited - yesterday was the first time I've ever been on a boat with a spinnaker, and it was quite a bit to take in - but we are hooked! My understanding that the "downhaul" is mounted close to the base of the mast, or "foreguy" in the more forward position. Am I to understand that with your twings mounted where they were, you didn't use downhaul or foreguy...? Or you always use downhaul, but not always the foreguy?
Posted By: Rhapsody #348

Re: Pinching or Backwinding the Main - 07/17/17 06:07 PM

We used the twings and did not use the foreguy (aka spin pole downhaul).
Posted By: last fling IV

Re: Pinching or Backwinding the Main - 07/17/17 11:35 PM

We always use a downhaul,nut not tight in light air. If you use a foreguy that is not near the base of the mast, you will have to adjust it every time you trim the pole fore or aft..
Posted By: Fitjarald

Re: Pinching or Backwinding the Main - 07/18/17 01:11 PM

Yes - we ran into the issue of constantly adjusting the downhaul for jibes, any time the guy is adjusted, etc, plus it's location means we have to disconnect it on every beat as it gets twisted around the jib sheets with the roller furling. However, I don't have any other deck hardware installed yet, so just trying to get a feel for the best methods others use, and then will make a decision once we are a bit more competent with the spinnaker.

The second set of blocks used near the stantion bases to keep the guy and sheet out of cockpit - do others jsut attach these to the rings on the stantion bases? Or would this apply too much pressure, and risk yanking the stantions out?
Posted By: Rhapsody #348

Re: Pinching or Backwinding the Main - 07/18/17 01:15 PM

I used to attach the twings to stanchion bases but the location isn't optimal and some have broken the welds on the stanchion bases. Anyone who has mounted padeyes on deck near the shrouds will tell you that is by far the best solution on twing placement. It eliminates the need for the foreguy. Make sure you drill and properly epoxy isolate the padeye holes and use a backing plate or large washers inside.
Posted By: Fitjarald

Re: Pinching or Backwinding the Main - 07/18/17 02:18 PM

Thanks! I also saw in the video in the thread you linked to previously the second set of blocks that the sheet and guy runs through after the running aft, to keep the guy and sheet from cutting diagonally across the cockpit. Would those be mounted to padeyes as well?
Posted By: Rhapsody #348

Re: Pinching or Backwinding the Main - 07/18/17 02:37 PM

Those are mounted on the stanchion base - the stanchion is located about even with the companionway entrance.
Posted By: NaturalHigh

Re: Pinching or Backwinding the Main - 08/17/17 05:20 PM

I have sailed both with downhaul at the base of the mast and forward at the middle of the foredeck. I honestly prefer the forward mounted downhaul as it gives much more stability to the pole as it creates a triangle of forces between the guy, uphaul and down haul. Yes, adjusting down haul for pole forward and back can suck, but so can constantly fighting with the pole moving back on the guy.

I agree that going for maximum point is the priority in everything except the very lightest of winds where you need to keep the boat moving. Sometimes that means the main is backwinded (we call it a speed bubble). Up at the top of #1 range we are seeing only the aft third of the main being backwinded, but we are still going close to 7 kts inside 25 degrees apparent. If you are light on crew, you will start back winding earlier as you are lowering the main to keep the heel appropriate. Start stepping down headsails if the main is starting to flog.

I agree with the trim approach of setting the headsail for maximum point and playing the main to find where the best speed is. If best speed is with main low enough that it is flogging even though it is as flat as plywood, it means it is time to reduce sail unless you like replacing windexes off the top.

Another secret weapon that doesn't get used is the reef. The J/30 is as fast as blazes with the #1 up and reef in the main. A reef is much faster to put in and shake out than a headsail peel and is especially effective where you are slightly overpowered at one end of the course. It is also really effective where you think you might be over powered with the kite up in high winds. Try it with a reef and the kite up, the stability improves and you might even be faster because you are fighting less with the rudder.

Another tip to save your stanchions: It is the only yacht I have been on that the spinnaker sheets like to be run inside the lifelines because it is so wide. It is better that the guy presses on the lifeline outwards when the pole is back vs the alternative where the force is exponentially higher when the pole is forward near the forestay.
Posted By: Conundrum

Re: Pinching or Backwinding the Main - 09/03/17 02:47 PM

On Conundrum, we have T Track with a Tweaker car located just aft of the beam. We run the tweaker from there to the shroud base then along the cabin to a cam cleat on the cabin side. Keeps the line flat and low. We always run spins INSIDE for reasons that Natural High gave. We no longer load the lifelines or stanchions with this setup..
Our Spinnaker pole lives in a sock on the Boom. When stowed the foretriangle is completely clear with the downhaul attached to the temporary spot at the base of the mast with a 5000# caribiner and swivel. When the pole is deployed we move this caribiner to the center deck padeye where it is most efficient. The uphaul and downhaul are always connected to the pole whether stowed or deployed.
Sail Fast, Sail Safe
BTW, Conundrum is for sale.
Posted By: Coastie

Re: Pinching or Backwinding the Main - 09/03/17 11:34 PM

Guys this part of the adventure is way beyond where I am now, but I really want to understand these deck setups better. While the written descriptions are very good, some images/video would really help. Don before you sell your boat please take some time and carefully detail for the rest of us how you have organized everything, kind of a posterity thing. Hopefully you will keep participating in this site when you move to the next boat. I for one really appreciate all the effort that you and BIll and many others have put into these boats and the boaters that like these boats.

I will even help with the effort. If you shoot the images and mail them to me, I will gladly resize them and do whatever is needed to get them up here. Then you can add descriptions and comments. This is an open offer, so anyone that has imagery that we should all be seeing, feel free to PM me or email at dmgraf55@centrurytel.net.

I really suspect that MaJic Carpet has many of the better deck features, but all I can see these days is balsa, more balsa, then epoxy...............
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