Association Forum - adjustable backstay

Assn Members Area · Join

Home.

Association Forum

Ships Store

Cruising

Racing

Technical Tips

Photo Gallery - New

Boat Search - Updated

Manuals & Brochures

Swap Meet

Links

Officer Flag Line & Staff

Bylaws & Constitution

Members Area

Join the Association

Notice:
The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.

Association Forum

Username:	Password:
Save Password
Forgot your Password?

All Forums

Catalina/Capri 25/250 Sailor's Forums

Catalina 25 Specific Forum

adjustable backstay

New Topic

Topic Locked

Printer Friendly

Author

Topic

MiNO
1st Mate

Member Avatar

USA
32 Posts

Initially Posted - 02/24/2010 : 12:42:35

I am currently about to replace my backstay, which is not adjustable, and was wondering if it is worth the money to upgrade to the adjustable one that they sell on Catalina Direct. They sell entire adjustable backstay package for $370 for the standard rig, while the regular backstay is $115.

I understand what the adjustable backstay does, but I'm not sure if it is worth it. Does anyone have any thoughts? I would like to try one out because I have never used one before. I don't race, but I am interested in having better performance while cruising. For those that have it, do you find yourself using it much? How much of an effect does it have on the Catalina 25 in a stiff breeze?

Thanks!
-Kurt

Edited by - on

windsong
Captain

Members Avatar

USA
318 Posts

Response Posted - 02/24/2010 : 16:15:49

I installed one on my C250 last weekend. I'm trying it out Sunday. I'll let you know. My feeling is that it will be MORE effective on our tender boats than it is on bigger boats, but that's only a guess. I'll let you know, though.

Edited by - windsong on 02/24/2010 16:16:12

Dave5041
Former Mainsheet Editor

Members Avatar

USA
3758 Posts

Response Posted - 02/24/2010 : 17:07:39

I don't think it adds a lot. It might be more significant with new sails, but I don't know. There isn't enough bend to flatten the sail much, but I do use it. My Harken roller rides over the forestay, so rig tension doesn't affect my jib luff. I generally loosen it to unload the rig at the dock. Different equipment may mean that ymmv.

Edited by - on

Steve Milby
Past Commodore

Members Avatar

USA
5902 Posts

Response Posted - 02/24/2010 : 18:05:10

If you think the C25 mast can't be bent very much, lay it down with each end on a sawhorse, and no support in the middle. It'll sag in the middle, and, if you lean on it in the middle, it'll sag much more.

The reason why the adjustable backstay doesn't seem to work very well on a masthead rig is because most people don't tune it correctly. They tune the adjustable backstay rig the same way that you tune the rig without an adjustable backstay, with roughly equal tension on all the stays. When you do that, the mast is held rigidly erect and straight, and, when you apply more backstay tension, the mast can't bend. All that does is to put more stress on the attachment points, without altering the shape of the sails

The stays have to be adjusted with different tensions, so that each stay either prevents the mast from bending in an undesirable direction, or allows the mast to bend in a desired direction.

When the rig is tuned correctly, the mast can be adjusted from very loose to very taut with only one adjustment. When you're sailing downwind, or, when sailing to windward in a lull, you can ease the backstay tension, and the sails will have a full, powerful shape. When you're sailimg to windward, or in a puff, you can increase backstay tension, and flatten (depower) the sails.

In the "Racing" section of this website, I posted a long article on racing tips, and explained how to tune the rig for an adjustable backstay. As I recall, that explanation is at the end of the article, on the last, or next to last page.

Edited by - on

Dave5041
Former Mainsheet Editor

Members Avatar

USA
3758 Posts

Response Posted - 02/24/2010 : 20:47:09

I am tuned fairly well and can certainly create visible bend and new sails would probably flatten more, as I suggested, but in my experience with my equipment I don't see a lot of improvement. I do not suggest that the mast doesn't bend, just that the results will vary with different states of equipment. Besides, adjustable backstays just look so cool

Edited by - on

DaveR
Master Marine Consultant

Members Avatar

USA
2015 Posts

Response Posted - 02/25/2010 : 06:38:51

I suppose this has as much to do with tuning my rig as the presence of the adjustable backstay, but I seem to point quite a bit better with my WK since I tuned the rig and tightened the adjustable backstay. I think it was Brooke Willson that warned me to keep the backstay loose at the dock so as not to over stress the rigging. Might not pay three times the price for one though .........

Edited by - on

MiNO
1st Mate

Members Avatar

USA
32 Posts

Response Posted - 02/25/2010 : 19:40:55

Thanks everyone! Steve, I've checked out your article on tuning and Racing... very useful!

Still haven't decided whether or not to get one.

Edited by - on

Steve Milby
Past Commodore

Members Avatar

USA
5902 Posts

Response Posted - 02/26/2010 : 07:24:25

[

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by MiNO
 Thanks everyone! Steve, I've checked out your article on tuning and Racing... very useful!

Still haven't decided whether or not to get one.<hr height="1" noshade id="quote"></blockquote id="quote">

I am an enthusiastic racer and used my adjustable backstay all the time. Racers often re-tune their rig before a race, so that it is perfectly tuned for the specific windspeeds that they will be sailing in. In effect, an adjustable backstay enables you to re-tune your rig on the fly. If the race starts in light air, and your rig is tuned loosely for light air, you can tighten up your rig with only one tug on a line to do it, without getting out your wrenches. I almost always eased the backstay every time I rounded a windward mark and bore off downwind. That's a really big deal for a racer, but it's usually not so much for a cruiser. I love to tweak sails, and do it constantly. Most cruisers aren't into tweaking that much. Whether an adjustable backstay would be worth the cost to you probably depends more on your personality than anything else. I'm definitely Type A, and can't sit still, knowing that there are lines to be tweaked. I don't begrudge an expense if it increases my enjoyment of the boat proportionately.

Edited by - Steve Milby on 02/26/2010 07:26:33

pastmember
Master Marine Consultant

Members Avatar

2402 Posts

Response Posted - 02/26/2010 : 08:48:35

Frank's Mantra:
Virtually all sail controls are used to depower a rig, therefore what most consider "racing" equipment is really safety equipment. A soft rig is a powered up sail plan, when your first mate wishes you would stand the boat up it is the very "racing" hardware she thought was boy toys that allows you to get the boat under control.
Just make sure you understand what it takes to add the second tang to your transom on this whole backstay thing.

Edited by - on

JimB517
Past Commodore

Members Avatar

USA
3285 Posts

Response Posted - 02/26/2010 : 18:37:19

Mine is totally tuned to the Milby/Crawford method. I usually sail with the backstay at half tension. In light air, a full ease on the backstay upwind will put about a 1/2 knot increase in boat speed on the knotmeter. I'm talking winds 3 to 4 knots and boat speed around 2. (Cruisers would be motoring).

As the wind pipes up, increasing tension increases pointing while flattening sails.

I do a full ease then harden up 1 or 2 inches downwind under spin.

Would I advocate spending $350 on this on a cruising boat? No. If you don't have outhaul, cunningham lines led aft do this first. If you don't adjust jib cars and traveler, get used to that it makes a huge difference. If your sails are old and baggy, its really not worth it. If your rig is not carefully tuned using a Loos gauge you won't see much benefit of the adjustable backstay.

Edited by - on

Peregrine
Admiral

Members Avatar

830 Posts

Response Posted - 02/26/2010 : 23:13:36

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by pastmember
 Frank's Mantra:
Virtually all sail controls are used to depower a rig, therefore what most consider "racing" equipment is really safety equipment.<hr height="1" noshade id="quote"></blockquote id="quote">
Sorry I disagree.
An adjustable backstay can add power and lift.
This is not a safety device it is an on fly tuning devise.
In light air you want to see 3-6 inches of sag in the forestay as the wind picks up you want to reduce that sag to 1-2 inches. You do that by easing the back stay in light air and cranking it in heavy air.
In light air ease the back stay to create shape in the headsail, in heavy air pull the mast back to point higher.
Racing, day-sailing or cruising an adjustable backstay can enhance your sailing experience.

Edited by - Peregrine on 02/27/2010 10:50:38

Steve Milby
Past Commodore

Members Avatar

USA
5902 Posts

Response Posted - 02/27/2010 : 06:29:59

I agree with Frank's general point that, anything that enables the boat to point higher enhances the boat's safety, because it means the boat will be better able to claw off a lee shore in a blow, but I'm not sure an adjustable backstay does that.

Before I learned how to tune the rig for the adjustable backstay, I sailed my C25 for many years with the rig well-tuned as if it was a fixed backstay. I haven't seen any reason to believe that a masthead-rigged boat with an adjustable backstay can point significantly higher than a well-tuned boat with a fixed backstay. I think it is a wide misconception that an adjustable backstay improves the boat's ability to point by depowering the sails when you're driving the boat to windward in stronger winds. What it does is to enable you to power up the sails when in light air and off the wind. In other words, it doesn't make the boat point higher than any boat with a well-tuned rig - it enables you to change the tuning of the rig so that it is always optimized, regardless of whether you're sailing to windward or off the wind.

IMHO, an adjustable backstay won't significantly improve your boat's windward ability. It will make it sail better off the wind and in light air.

Edited by - Steve Milby on 02/27/2010 06:32:47

Even Chance
Captain

Members Avatar

USA
393 Posts

Response Posted - 02/27/2010 : 07:39:14

Steve, I beg to differ (I think): Hardening the forestay improves pointing. If you have a non-adjustable backstay and the forestay and backstay are tuned tight, then you're right: an adjustable backstay won't improve pointing. On the other hand, if you have some sag for the sake of powering up, then hardening the system does improve pointing. At least it does on my boat.

Edited by - on

Steve Milby
Past Commodore

Members Avatar

USA
5902 Posts

Response Posted - 02/27/2010 : 08:42:38

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Even Chance
 Steve, I beg to differ (I think): Hardening the forestay improves pointing. If you have a non-adjustable backstay and the forestay and backstay are tuned tight, then you're right: an adjustable backstay won't improve pointing. On the other hand, if you have some sag for the sake of powering up, then hardening the system does improve pointing. At least it does on my boat.
<hr height="1" noshade id="quote"></blockquote id="quote">We agree, Brooke. You're correct in saying that hardening the forestay improves pointing, but a C25 can't point any higher than it's design permits, no matter how much tension you add to the forestay. As tension is added to the wire forestay, it becomes more rigid, with less sag, up to a point. If you continue to increase tension on the forestay after you have taken all the sag out of it, you won't change the shape of the sails anymore. All you'll be doing is overstressing the attachment points.

What I'm saying is that, by adjusting the turnbuckles on a boat with a fixed backstay, you can take just as much sag out of the forestay as you can with a backstay adjuster. Thus, both boats can point equally close to the wind.

The question is, what can an adjustable backstay do for you that a fixed backstay can't? The adjustable backstay can be used to instantly release all that forestay tension, creating sag in the forestay and increasing the power of the jib when you want to sail downwind, or in lighter winds. A boat with a fixed backstay can't do that without getting out some tools and adjusting the turnbuckles.

That's why I say, contrary to popular opinion, an adjustable backstay doesn't let the boat point higher than it could if the fixed backstay was well-tuned. It lets you instantly change the tuning of the rig, to optimize it for any changes in your course or windspeed.

Edited by - on

Peregrine
Admiral

Members Avatar

830 Posts

Response Posted - 02/27/2010 : 10:54:34

There are backstay adjusters that do not require a split backstay.

I cannot vouch for the forces that would be put on the C-25's fitting but it would make adding an adjuster much easier.

Edited by - on

Steve Milby
Past Commodore

Members Avatar

USA
5902 Posts

Response Posted - 02/27/2010 : 11:26:39

Harken makes a system for small cruising boats with a single backstay that looks pretty good, and it appears to be moderately priced. http://www.mauriprosailing.com/Merchant2/merchant.mvc?Screen=CTGY& Store_Code=MPS& Category_Code=HARBACKSYS1

I have no experience with that particular system, but the Harken brand is a good one.

Edited by - on

Even Chance
Captain

Members Avatar

USA
393 Posts

Response Posted - 02/27/2010 : 12:20:36

<blockquote id="quote">quote:<hr height="1" noshade id="quote">We agree, Brooke. You're correct in saying that hardening the forestay improves pointing, but a C25 can't point any higher than it's design permits, no matter how much tension you add to the forestay. As tension is added to the wire forestay, it becomes more rigid, with less sag, up to a point. If you continue to increase tension on the forestay after you have taken all the sag out of it, you won't change the shape of the sails anymore. All you'll be doing is overstressing the attachment points.
<hr height="1" noshade id="quote"></blockquote id="quote">

Of course you can't point higher than the boat can point. The other thing the adjustable backstay does is bend the mast, flattening the main in big wind. That's Frank's de-power axiom.

Edited by - Even Chance on 02/27/2010 12:20:55

Peregrine
Admiral

Members Avatar

830 Posts

Response Posted - 02/27/2010 : 14:51:12

Thanks for this thread it has made me go back and review the concepts of draft control.
For a clearer idea of luff tension which can be controlled with an adjustable backstay read pages 107>109 in Wallace Ross' "Sail Power"
Sorry, tried to leave a click-able link but the code does not seem to be working.

Quote from fig. 87 page 108;

"Luff sag increases as wind velocity increases and creates two problems.
First, the luff moving aft creates more draft in the sail just when a flatter sail is needed.
Second, the luff moving aft allows the entire central section of the sail to swing aft and, at the same time, move to the side of the boat. As a result the forces on the sail are less forward and more to the side. The sail has therefore, more draft at an increased sideways angle." 

A long winded way to say less sag in heavier air will help you point but...
IMO he is saying creating less sag will keep the forces moving you forward instead of sideways, it does not indicate it does this by depowering the sail.

Edited by - on

dmpilc
Master Marine Consultant

Members Avatar

USA
4593 Posts

Response Posted - 02/28/2010 : 07:08:10

I can vouch for the 6:1 block set-up on a non-split backstay. I have that on our C-22 and it works well. All that is required is shortening the backstay about 2-3 ft. DO NOT try a 4:1 set-up, you'll need the 6:1 power.

Edited by - on

Topic

New Topic

Topic Locked

Printer Friendly

Jump To:

Association Forum

Notice: The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.