Cascade Backstay - When & how much?
Moderators: sderby, Tim Bosma, Tom Elsen
Cascade Backstay - When & how much?
I'm in the process of doing the splicing for a new backstay with a Melges 24 kicker to replace the pinch type on #171. I know the advantage in light air - release the backstay to get it out of the way of the main, but how much should be on after the tack? I realize it depends on the wind, but assuming I don't need to flatten the main, can I leave it off? Are our spreaders swept back enough to support the mast without any backstay?How about going downwind, I've always released the backstay and it maxed itself out (no slack in the control lines); do I need to tighten it up or will "full-off" be ok with a kite up? I guess I'm old-school, it kind of scares me to replace SS wire with a tiny rope!
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Tom Elsen
- Site Admin
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- Location: Minneapolis, MN & Chicago, IL
Hey Gary -
Great question. I've been meaning to post on this topic for a while.
Just MHO, but with the new system I think it's important to have a little backstay on (downwind) starting in winds in ~ 7- 8kts. Generally, here's what we do:
- Under 7, no worries
- 7 - 10, slack out of the backstay (batten straight, but no tip bend)
- 10 - 12, backstay on 1/4
- 12 - 14, on 1/2
- 15 - 17, on 3/4
-18+, on full
Be sure to replace the line every two years or so, as you know.
AND, and, and DO NOT let any slack-brain gomers pull your backstay on like they did the old model. There's a LOT more power in the new system. So unless you've got a designated mast-catcher onboard, don't pull the hell out of the thing.
Great question. I've been meaning to post on this topic for a while.
Just MHO, but with the new system I think it's important to have a little backstay on (downwind) starting in winds in ~ 7- 8kts. Generally, here's what we do:
- Under 7, no worries
- 7 - 10, slack out of the backstay (batten straight, but no tip bend)
- 10 - 12, backstay on 1/4
- 12 - 14, on 1/2
- 15 - 17, on 3/4
-18+, on full
Be sure to replace the line every two years or so, as you know.
AND, and, and DO NOT let any slack-brain gomers pull your backstay on like they did the old model. There's a LOT more power in the new system. So unless you've got a designated mast-catcher onboard, don't pull the hell out of the thing.
Best wishes,
Tom
Tom
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grandillusion
- Posts: 172
- Joined: Tue Oct 31, 2006 12:42 am
- Location: South Havenish
All of this is just one more reason why the DRIVER is supposed to be pulling the thing to begin with! Only the person who's on the helm gets the instant feedback from backstay/mainsheet/traveler/vang, not necessarily in that order. The very counterbalanced rudder blade on the 7.9 already tones the feedback down way too much IMHO. Having someone else work the mainsail controls just adds fuel to the fire as far as the over/under trimming of the controls go. I realize that there are those out there who disagree bacause of strength and sailing skill but I have only one answer for that: If you always let someone else do these things you will NEVER build the skills that are REQUIRED to do them yourself. Just as in tacking the genoa on any boat at it's upper wind range [or not !], there's just as much technique involved to doing it quickly and correctly as there is brute strength............................... 
Installing the cascading backstay will bring you the same joy as going from a manual opening garage door to an automotic, remote lift. And there will be a lot less colorfull mephafors when you jibe in light air.
Upwind you need to adjust the backstay tension according to forestay sag but the best advise is to consult your sailmaker. We sail with the backstay comletely off downwind in all wind strengths with great results.
Upwind you need to adjust the backstay tension according to forestay sag but the best advise is to consult your sailmaker. We sail with the backstay comletely off downwind in all wind strengths with great results.
"Upwind you need to adjust the backstay tension according to forestay sag but the best advise is to consult your sailmaker. We sail with the backstay comletely off downwind in all wind strengths with great results."
I agree with this with a couple of caveats. I'm one of those who is always testing the rig and sails to see if the boat/wind/sea conditions can/will handle a higher gear [flatter sails]. Some long time very famous sailors like Dr. Stuart Walker say just the opposite. Apparently, he and those who think this way never sailed cats much! When ANY boat gets close to the maximum lift:drag ratio for it's current sail setting and wind and sea conditions, it's the same thing as winding an engine out in a certain gear. There comes a point that the only way to go any faster is to shift to a higher gear and in a sailboat that means going to flatter sail shapes. This doesn't make sense to some folks but Randy Smyth explained it very well back in the 80's. He said " when you have more lift than you can use, the only way to go any faster is to minimize drag". Randy was speaking mainly of trapezing conditions and up but this concept applies across the board and one will never realize it's truth and the resulting benefits to upwind speed unless they are willing to buck the tuning guide from time to time! Remember, there ain't no free lunch: anytime you increase lift you also increase drag and vice-verse. Full sails make lots of lift but at the expense of lots of drag!!!
On any boat that I sail, I set the rig up for the LIGHTEST expected conditions because without the needed low gears, accelerating away from the start, out of tacks and through boat wakes/bad waves is a loosing proposition and that frequently means that my rig is looser than the guide says or anyones elses rig is. Depending on the sailmaker, some tuning guides/classes say to NEVER touch the backstay until a certain wind speed is reached. This is CRAZY!!
You will never learn if your boat is capable of going any faster in ANY conditions unless you semi-continually experiment with the the flattening controls, and on a boat with a backstay adjuster, that is control numero uno!
I'm not suggesting that anyone ignore their tuning guide, just that they remember and take to heart the title: it's a GUIDE, not a set in stone book of rules that MUST be adhered to or else!
One last thing before anyone jumps on the " I'm not in a cat" bandwagon. Cats keep going faster to a point as long as they have enough righting arm [weight on the traps, racks, whatever]. Most keelboats are limited by hull speed and most smaller keelboats won't do hull speed upwind, and guess why: too much DRAG on the rig/sails/deck and hull for the total driving force that can be generated! But, and this is a big but, wouldn't you rather reach the maximum speed for "X" conditions FOR YOUR BOAT sooner than those around you AND be able to achieve a HIGHER maximum speed than those around you, even if it's only 10ths or 100ths of a knot more?
I agree with this with a couple of caveats. I'm one of those who is always testing the rig and sails to see if the boat/wind/sea conditions can/will handle a higher gear [flatter sails]. Some long time very famous sailors like Dr. Stuart Walker say just the opposite. Apparently, he and those who think this way never sailed cats much! When ANY boat gets close to the maximum lift:drag ratio for it's current sail setting and wind and sea conditions, it's the same thing as winding an engine out in a certain gear. There comes a point that the only way to go any faster is to shift to a higher gear and in a sailboat that means going to flatter sail shapes. This doesn't make sense to some folks but Randy Smyth explained it very well back in the 80's. He said " when you have more lift than you can use, the only way to go any faster is to minimize drag". Randy was speaking mainly of trapezing conditions and up but this concept applies across the board and one will never realize it's truth and the resulting benefits to upwind speed unless they are willing to buck the tuning guide from time to time! Remember, there ain't no free lunch: anytime you increase lift you also increase drag and vice-verse. Full sails make lots of lift but at the expense of lots of drag!!!
On any boat that I sail, I set the rig up for the LIGHTEST expected conditions because without the needed low gears, accelerating away from the start, out of tacks and through boat wakes/bad waves is a loosing proposition and that frequently means that my rig is looser than the guide says or anyones elses rig is. Depending on the sailmaker, some tuning guides/classes say to NEVER touch the backstay until a certain wind speed is reached. This is CRAZY!!
You will never learn if your boat is capable of going any faster in ANY conditions unless you semi-continually experiment with the the flattening controls, and on a boat with a backstay adjuster, that is control numero uno! I'm not suggesting that anyone ignore their tuning guide, just that they remember and take to heart the title: it's a GUIDE, not a set in stone book of rules that MUST be adhered to or else!
One last thing before anyone jumps on the " I'm not in a cat" bandwagon. Cats keep going faster to a point as long as they have enough righting arm [weight on the traps, racks, whatever]. Most keelboats are limited by hull speed and most smaller keelboats won't do hull speed upwind, and guess why: too much DRAG on the rig/sails/deck and hull for the total driving force that can be generated! But, and this is a big but, wouldn't you rather reach the maximum speed for "X" conditions FOR YOUR BOAT sooner than those around you AND be able to achieve a HIGHER maximum speed than those around you, even if it's only 10ths or 100ths of a knot more?
I didn't say but thought that it would be obvious: use your knot meter and/or GPS while making SMALL adjustments. I prefer the GPS. The time lag is only about 1-1.5 seconds and it's WAY more accurate. If your knot meter send unit isn't located exactly on centerline and facing exactly straight ahead it WON'T read the same on both tacks.