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dpjosuns

J/29 Mainsail/Backstay issue

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We got a new mainsail for our 29 and we've run into a problem with the backstay.

 

The issue is that the leach sometimes gets stuck on the backstay. When there's air, its no problem, the thing just goes right through. However, when there's not, which is often, it gets hung up. Typically, we can just pop it over, but that's still a pain in the ass and in light air racing, kills speed.

 

My thought is to get a flicker like what are on the Melges 24 and 32's. Has anyone else ran into this problem? Any other solutions?

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We got a new mainsail for our 29 and we've run into a problem with the backstay.

 

The issue is that the leach sometimes gets stuck on the backstay. When there's air, its no problem, the thing just goes right through. However, when there's not, which is often, it gets hung up. Typically, we can just pop it over, but that's still a pain in the ass and in light air racing, kills speed.

 

My thought is to get a flicker like what are on the Melges 24 and 32's. Has anyone else ran into this problem? Any other solutions?

Get a legal sail made

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[Get a legal sail made

 

That's a pretty stupid reply to a request for help on a common problem. Just because the sail overlaps the backstay does not mean it has oversize girths. In fact, many boats would require dramatically undersized girths to not hit the backstay.

 

The answer to the problem isn't only hardware, it's technique. The flicker will do no good unless the backstay is very slack. Upwind that isn't likely to be the case except in light air on a fractional rig. Downwind the flicker will help but not perfectly. Full length top battens add to the problem, so be sure it has no more tension than absolutely needed to get the wrinkles out.

 

Upwind the technique in light air is a combination of a snappy roll tack and a monster ease on the sheet just before the leech hits the stay in mid tack. The roll will add some force to the sail to push it through and the ease will unload the leech and battens and allow it to flex through. The trick is timing and retrimming to the right twist to accelerate out of the tack. It takes practice.

 

Downwind is a bit easier as the sail can have more momentum helping it as it passes. In light air, I find stopping the boom by hand in mid gybe when the boom is still over the old leeward quarter will often pop the top batten and allow it to clear easier. Easy enough on boats up to about 40' but dodgy on bigger ones.

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[Get a legal sail made

 

That's a pretty stupid reply to a request for help on a common problem. Just because the sail overlaps the backstay does not mean it has oversize girths. In fact, many boats would require dramatically undersized girths to not hit the backstay.

 

The answer to the problem isn't only hardware, it's technique. The flicker will do no good unless the backstay is very slack. Upwind that isn't likely to be the case except in light air on a fractional rig. Downwind the flicker will help but not perfectly. Full length top battens add to the problem, so be sure it has no more tension than absolutely needed to get the wrinkles out.

 

Upwind the technique in light air is a combination of a snappy roll tack and a monster ease on the sheet just before the leech hits the stay in mid tack. The roll will add some force to the sail to push it through and the ease will unload the leech and battens and allow it to flex through. The trick is timing and retrimming to the right twist to accelerate out of the tack. It takes practice.

 

Downwind is a bit easier as the sail can have more momentum helping it as it passes. In light air, I find stopping the boom by hand in mid gybe when the boom is still over the old leeward quarter will often pop the top batten and allow it to clear easier. Easy enough on boats up to about 40' but dodgy on bigger ones.

My main doesn't get stuck.

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Thanks A3. I was wondering whether it could also be a technique issue, which it seems to be. We're newish to the boat, so that helps considerably.

 

The top battens are full length, so maybe that's another thing we'll get to toy around with. Figuring it out half the fun though, right?

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Thanks A3. I was wondering whether it could also be a technique issue, which it seems to be. We're newish to the boat, so that helps considerably.

 

The top battens are full length, so maybe that's another thing we'll get to toy around with. Figuring it out half the fun though, right?

What loft made the sail? Different sail makers will put their girths in different places. Do you race under PHRF Mid-Atlantic?

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It's a UK sail. I'm not sure, however, where it was made. I'll have to defer to the boss-man on that one. We race on the West side of Michigan on, of course, Lake Michigan.

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051.jpg

 

This J/29 has a slight penalty main (code 6 I think) but goes pretty darn quick. Look close and you can see the long backstay whip.

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It's a UK sail. I'm not sure, however, where it was made. I'll have to defer to the boss-man on that one. We race on the West side of Michigan on, of course, Lake Michigan.

Another question, MH or Frac? If you've got a MH you really should have that much trouble with the roach clearing through unless it's really light. If it hangs have some one pull straight down hard on the boom as far aft as they can and that should clear it.

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051.jpg

 

This J/29 has a slight penalty main (code 6 I think) but goes pretty darn quick. Look close and you can see the long backstay whip.

 

Having sailed on that particular J dozens of times, yes it is a code 6. In that particular photo, the whip was really getting old and sagging a lot more than when it was new. It should be replaced.

 

Technique also helps, as described above. If it's still fouled up after a tack or gybe is complete, your maintrimmer should grab the boom and do a quick L shaped manouver, pulling it 12inches to windward immediately followed by hanging on it for 1 second. It helps if he checks to make sure nobody had their head near the boom before he does this.

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051.jpg

 

This J/29 has a slight penalty main (code 6 I think) but goes pretty darn quick. Look close and you can see the long backstay whip.

 

Having sailed on that particular J dozens of times, yes it is a code 6. In that particular photo, the whip was really getting old and sagging a lot more than when it was new. It should be replaced.

 

Technique also helps, as described above. If it's still fouled up after a tack or gybe is complete, your maintrimmer should grab the boom and do a quick L shaped manouver, pulling it 12inches to windward immediately followed by hanging on it for 1 second. It helps if he checks to make sure nobody had their head near the boom before he does this.

Noticed that the spinnaker halyard exits a bit higher than the class exit point. How high is that above the "stock" exit point?

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I think Ballyhoo(frac) had a backstay whip as well, plus I've seen them on Pearson Flyers. Seemed to work well.

 

What "turbo" frac is that? How well did it do against the MH's? Looks good.

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We got a new mainsail for our 29 and we've run into a problem with the backstay.

 

The issue is that the leach sometimes gets stuck on the backstay. When there's air, its no problem, the thing just goes right through. However, when there's not, which is often, it gets hung up. Typically, we can just pop it over, but that's still a pain in the ass and in light air racing, kills speed.

 

My thought is to get a flicker like what are on the Melges 24 and 32's. Has anyone else ran into this problem? Any other solutions?

lucky you that you can test the sail in Michigan in January -

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I think Ballyhoo(frac) had a backstay whip as well, plus I've seen them on Pearson Flyers. Seemed to work well.

 

What "turbo" frac is that? How well did it do against the MH's? Looks good.

 

Ballyhoo (frac) does have a whip. It works pretty well, occasionally got stuck, but works most of the time. Only got stuck in really light wind.

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Ours is a MH rig. I'm certainly glad that we're not the only people who have had this 'problem'. We do do a ton of light air sailing. Was the whip that helpful?

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Noticed that the spinnaker halyard exits a bit higher than the class exit point. How high is that above the "stock" exit point?

 

It's about 10-12 inches, IIRC.

 

What "turbo" frac is that? How well did it do against the MH's? Looks good.

 

Rhumbline out of Vancouver, BC. It has code 6 main, code 5 headsail, and code 6 kite (hence the higher hoist). Rates level against the mastheads and does very well. Upwind it's the same boatspeed but just a tiny bit less point. Downwind it's a tiny bit faster. Works out equal in the wash.

 

Apparently, it keeps up with a Goman Express 20!!

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Ours is a MH rig. I'm certainly glad that we're not the only people who have had this 'problem'. We do do a ton of light air sailing. Was the whip that helpful?

The whip won't do much good if you pull your rig forward going downwind, your backstay will be tight. Another thing to consider as well is batten tension. Loosen it up in lighter air to allow the sail to pump through during gybes and tacks. If your sailmaker did not make it an adjustable pocket, he should have, the RBS System works pretty well and is good for repeatable settings.

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Ours is a MH rig. I'm certainly glad that we're not the only people who have had this 'problem'. We do do a ton of light air sailing. Was the whip that helpful?

 

Not really going to help much with a MH. As Will stated, a looser top batten/light air batten will help.

 

Also, teflon impregnated tape stuck on both sides of the top batten pocket will help.

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I just love it when someone gets clever and bumps up the roach and adds extra battens and ends up fighting with it so much that they slow down. Why do you need five battens for a J29 main other than to ensure it hooks up on the backstay? I've seen some boats extend the crane to give a bit of clearance and they end up twisting the mast. The flicker works ok on a frac where you can let the backstay off completely, but is nearly useless on a masthead.

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This happens on all of the J/30's I've raced on (5-6). Up to 8 knots it's a problem. Above that it goes away. In light air the helmsman just pumps the backstay as he goes by while tacking/gybing. The boats use Z and North Sails. Forgive my ignorance but do frac 29's and 30's use the same stick?

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Forgive my ignorance but do frac 29's and 30's use the same stick?

 

No. The frac stick is taller. RJ tried to make the two rigs as equal as possible. After years of data, turns out that the MH is a little faster in the light stuff, and they are nearly dead equal in the heavy stuff.

 

Edit: oops I misread your post. I thought you were asking about the MH vs Frac J29s. I'm not 100% certain but I believe the 29 has a taller stick than the 30.

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yeah we can definitely adjust the batten tension. we'll make sure to back that off even more.

 

This is a great place to start. Some of the more competitive boats I have sailed OD with have several upper battens of varying stiffness and would change them according to wind speed to help control twist in light air as well as the batten hanging issue.

Although the pulling down and to windward on the boom works, it is highly disruptive to your trim, and in light conditions, likely highly disruptive to the weighting of the boat as well.

Concentrating on the ease thru the tack, as well as the hard roll of the boat is another great place to focus effort on.

Remember that a keel boat like the 29 takes time to accelerate. Don't be afraid to get a little footy out of tacks and give the main the opportunity to clear. It may in the end be more of an acceleration benefit than holding onto that quarter of a lane.

 

A great way to practice the roll is to tie your tiller centered on a deep downwind. By getting your crew to roll together, you can, if done right, gybe the boat without the tiller.

This will give everyone an opportunity to figure out how to effectively transfer weight ( where hands and feet need to be, at what time. . . etc.). It's tough to do, but I promise it can be done. When it happens, you'll feel the acceleration.

 

This may be more than you need to hear, but I hope it helps.

 

-PKGB

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I was having the same problem with a new main also (not a J29). Top two battens are full length. We laid the new sail out on the loft floor and found a couple of possible culprits. The battens were 3/8" longer than they needed to be causing the batten and batten pocket tounge to stick out way past the leech of the main. We shortened the battens which allowed the batten pocket tounge to almost flush out against the leech. We also went wih a softer batten. Another thing we noticed was that the stiching on the back part of the batten pocket was being pulled back by hanging up on the backstay. Some teflon tape over the stitching fixed that. I was also advised to run the backstay a little looser than I had been (light air). By doing all of the above the problem has virtually gone away.

mm

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Forgive my ignorance but do frac 29's and 30's use the same stick?

 

No. The frac stick is taller. RJ tried to make the two rigs as equal as possible. After years of data, turns out that the MH is a little faster in the light stuff, and they are nearly dead equal in the heavy stuff.

 

Edit: oops I misread your post. I thought you were asking about the MH vs Frac J29s. I'm not 100% certain but I believe the 29 has a taller stick than the 30.

 

 

The J30 and J29 frac have the exact same lenght mast as well as section. The "P" dimension and I dimension on the J29 are slightly greater than the J30.

 

J29 frac P= 38.8'

j30 P = 38'

 

J29 frac I = 35'

J30 I = 34.9'

 

The frac J29 has a 4 foot taller mast than the MH J29.

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While on the topic of backstays, I want to ditch the "two blocks attached to the ring/triangle pincher arrangement". See photo.

 

post-6307-1265155472_thumb.jpg

 

What have others done?

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While on the topic of backstays, I want to ditch the "two blocks attached to the ring/triangle pincher arrangement". See photo.

 

post-6307-1265155472_thumb.jpg

 

What have others done?

 

I know on Lynx (Newport) we have a purchase system with an inverted cam cleat cam and a spectra backstay. If I'm not mistaken, its a strop coming off of a thru deck mount, a harken triple/triple purchase and then the spectra stay. I don't have any pics, but can look into it as the season comes around.

 

Then again we also have a sail drive and a few other cool little tricks. . .

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Sounds like the sailmaker bumped out the roach as square tops are king right now. Unsure of the language in the J29 rules but the J30 rules allow a shorter E to increase the roach.

 

 

It's a UK sail. I'm not sure, however, where it was made. I'll have to defer to the boss-man on that one. We race on the West side of Michigan on, of course, Lake Michigan.

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While on the topic of backstays, I want to ditch the "two blocks attached to the ring/triangle pincher arrangement". See photo.

 

post-6307-1265155472_thumb.jpg

 

What have others done?

 

 

I know the J29 racing in our area went to a hydraulic backstay with just a piece of spectra run up and thru a block then down to a hydraulic pump.

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Forget the hydraulics on the 29. Heavy, and they eventually leak. Plus, they're illegal by class rules. (don't know if you care about that or not)

 

Is it a frac or MH?

 

The fracs do not need much purchase on their backstays. The MH, you can go to a 48:1 (3 X cascade), with a vectran backstay. This can be lead to the helmsman or maintrimmer.

 

PM me if you need more details/photos/help.

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Actually hydraulics on the J29 are very good...it just oil cans the crap out of the boat and Ira is right, they eventually make a nice mess. Otherwise the boat goes upwind quite nicely.

 

I have attached a pic of our backstay purchase system. If the boat stays with me this year we plan on adding an extra purchase to make the whole system 72:1. IIRC, Hustler has this system and it is outstanding.

 

I have to agree with those folks who said softer batten or loosen it up. Should resolve the problem easily.

 

Good luck.

 

4thofJuly2003001.jpg

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Forget the hydraulics on the 29. Heavy, and they eventually leak. Plus, they're illegal by class rules. (don't know if you care about that or not)

 

Is it a frac or MH?

 

The fracs do not need much purchase on their backstays. The MH, you can go to a 48:1 (3 X cascade), with a vectran backstay. This can be lead to the helmsman or maintrimmer.

 

PM me if you need more details/photos/help.

 

Interesting about the class rule issue, I know this boat raced the west coast championships but he may have replaced the backstay for it. It is a masthead OB J29. All I know is it seems to be working for him very well.

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Yeah, its a MH, with a non-hydro backstay. We really dont have much trouble with the backstay on and off. I'll have to verify what the purchase is, but it looks like Divide in the photo above.

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Actually hydraulics on the J29 are very good...it just oil cans the crap out of the boat and Ira is right, they eventually make a nice mess. Otherwise the boat goes upwind quite nicely.

 

I have attached a pic of our backstay purchase system. If the boat stays with me this year we plan on adding an extra purchase to make the whole system 72:1. IIRC, Hustler has this system and it is outstanding.

 

I have to agree with those folks who said softer batten or loosen it up. Should resolve the problem easily.

 

Good luck.

 

4thofJuly2003001.jpg

 

This is exactly the set-up I was thinking with the addition of a double to allow adjustment of either side of the cockpit. Thanks Disbursed for the PM and phots of Mostly Harmless as well.

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Interesting about the class rule issue, I know this boat raced the west coast championships but he may have replaced the backstay for it. It is a masthead OB J29. All I know is it seems to be working for him very well.

class rules don't seem to apply on the west coast.

- required membership in the organization isn't met;

- old boats with too many modifications in the base stock;

- i've been asking on the J29 forums for even a conversation about keel offsets and am met with silence (if i'm going to make templates, i might as well know why the offsets have been suspended).

 

it's great just to get 4 boats on the line. class rules are a nice idea that just isn't practical out here.

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Interesting about the class rule issue, I know this boat raced the west coast championships but he may have replaced the backstay for it. It is a masthead OB J29. All I know is it seems to be working for him very well.

class rules don't seem to apply on the west coast.

- required membership in the organization isn't met;

- old boats with too many modifications in the base stock;

- i've been asking on the J29 forums for even a conversation about keel offsets and am met with silence (if i'm going to make templates, i might as well know why the offsets have been suspended).

 

it's great just to get 4 boats on the line. class rules are a nice idea that just isn't practical out here.

Keel and rudder offsets are suspended if you look in the class rules. Put an 8 foot bulb on there!

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Interesting about the class rule issue, I know this boat raced the west coast championships but he may have replaced the backstay for it. It is a masthead OB J29. All I know is it seems to be working for him very well.

class rules don't seem to apply on the west coast.

- required membership in the organization isn't met;

- old boats with too many modifications in the base stock;

- i've been asking on the J29 forums for even a conversation about keel offsets and am met with silence (if i'm going to make templates, i might as well know why the offsets have been suspended).

 

it's great just to get 4 boats on the line. class rules are a nice idea that just isn't practical out here.

Keel and rudder offsets are suspended if you look in the class rules. Put an 8 foot bulb on there!

 

yeah, i know ... but WHY were they suspended? is the math that hard?

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Interesting about the class rule issue, I know this boat raced the west coast championships but he may have replaced the backstay for it. It is a masthead OB J29. All I know is it seems to be working for him very well.

class rules don't seem to apply on the west coast.

- required membership in the organization isn't met;

- old boats with too many modifications in the base stock;

- i've been asking on the J29 forums for even a conversation about keel offsets and am met with silence (if i'm going to make templates, i might as well know why the offsets have been suspended).

 

it's great just to get 4 boats on the line. class rules are a nice idea that just isn't practical out here.

Keel and rudder offsets are suspended if you look in the class rules. Put an 8 foot bulb on there!

 

yeah, i know ... but WHY were they suspended? is the math that hard?

It boils down to JBoats but it should not be that complicated. The offsets are what Johnstone designed, the keel and rudder are not at those dimensions out of the factory. Not even close. So some people will grind and fair and build the blades to the "designed" dimensions but this can conflict with the rules concerning not changing the boat from stock. So the easy way out was to just suspend the offsets so there are no illegal keels and rudders.

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Interesting about the class rule issue, I know this boat raced the west coast championships but he may have replaced the backstay for it. It is a masthead OB J29. All I know is it seems to be working for him very well.

class rules don't seem to apply on the west coast.

- required membership in the organization isn't met;

- old boats with too many modifications in the base stock;

- i've been asking on the J29 forums for even a conversation about keel offsets and am met with silence (if i'm going to make templates, i might as well know why the offsets have been suspended).

 

it's great just to get 4 boats on the line. class rules are a nice idea that just isn't practical out here.

Keel and rudder offsets are suspended if you look in the class rules. Put an 8 foot bulb on there!

Exactly! Just pm Julian to get some tips on how to do this in one design without a hassle

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It boils down to JBoats but it should not be that complicated. The offsets are what Johnstone designed, the keel and rudder are not at those dimensions out of the factory. Not even close. So some people will grind and fair and build the blades to the "designed" dimensions but this can conflict with the rules concerning not changing the boat from stock. So the easy way out was to just suspend the offsets so there are no illegal keels and rudders.

 

thank you.

and i agree with condor.

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