Marlow-Hunter Rigging.

[Paul L]

Originally Posted by skipmac

Isn't that more or less what he said?

"unless you fly a spinnaker or sail a planing boat."

I generally think that a modern underbody implies a planning or semi planing hull.

I don't know what you consider planing. I don't consider my old J37 a planning boat, but it sure could surf for a long period. It definately did better heading up higjherntjan DDW. I have a much heavy boat now. We still typically put in a few long jibes when going to DDW destination. Obviously you need enough sail area to make it work, weather that's a Genoa or an asym.

[malbert73]

Originally Posted by sailorboy1

I can, are you really interested?

Larger main with a longer boom, shorter mast with less weight up high. Center of movement further aft, less weather helm (for me if I have 5 degrees of rudder it means I don't have the boat balanced). The only real time get any weather helm is at 8 knots if a gust heels the boat.

Boat is easy to balance and normally sails along with little rudder and a light wheel. And I make this comparison to my last boat of a Cal-39 that always had weather helm. Heck I run around with the autopilot set on a response of 2 or 10 because don't need that much to steer straight.

Unlike a lot of boats I see sailing around with only their head sail out, I never sail without the main, because that would be a waste on a B&R. I rarely roll up the head sail and will reef the main at 15 knots without any lost of boat speed.

Aft sheeting on the main using the Hunter cockpit bridge; a lot less effort needed to crank it in and it even uses a smaller winch.

Just a great rig that is easy to balance and easy to sail. I just fail to understand what more people want of their rig. The rig does all Hunter says it will do, but keep in the end that they didn't come up with it and don't build it as it is a Selden rig. Hunter just had the guts to use it!

Some of the "negatives" people talk about:

1- No back stay - so what! The rigs aren't falling down and by not having the backstay in the way is how you get the big shorter main. And even more room in the cockpit.

2 - can not let the sail out down wind - just plain wrong and BS! The main has wear patches on the main to allow you to do that if you what to. I sail mine downwind and even wing-on-wing regularly (people say it is not possible, must be them). I don't have an issue putting the main on the spreaders if needed to allow this and yet still have the original 13 year sail with the original wear patches that haven't been replaced. But I don't make it a habit of sailing deep downwind as I know for a fact that the boat is faster sailing off the wind. And yes I have a spinnaker and fly it!

3. loose backstay - that's by design and if you don't believe me look it up yourself in the tuning instructions from Selden. Bothered me originally that the forestay was loose, but in the end I decided the designers of the rig knew more than me. There isn't a need to crank down on a backstay to keep the foresail shape because the sail is cut for a loose forestay and the mast already has a lot of rake.

The only real difference between the B&R rig and lots of other rigs with swept back spreaders is that it has the tripod design where the mast and side stays are doing the support of the rig so you don't need a backstay or a tight forestay. Some rake is lost for those with furling masts, but if someone has a furling mast they are making that trade-off.

The real issue is that people don't learn to sail the boat the way it is designed. It isn't the rigs fault if you try to sail it as a conventional rig and it doesn't perform. Just as it isn't a modern boat's fault if you try to sail it like a boat of yester year that had a lot of fore/aft hull overhang as you still think you need to put the rail in the water.

I don't consider myself a great sail trimmer. But I just sail my B&R rig the way it and the boat as a whole likes to be sailed. If others can not do the same it isn't the rigs fault, it's their fault!

So in the end, if you have experience on a B&R rig and couldn't get it to sail good then it was you! Or at the least you can not sail as well as Fat Don!

great info and opinion. Thanks! I think the one thing you reference which is truly better is the ability to have a fuller, even square topped mainsail for better performance, and a smaller jib. Too bad most seem to use in mast furlers which negates this.

Two questions:
I assume you must be the minority with a conventional battened main?
You reference a loose backstay above in #3 which I assume must be due to "backstay envy"??

[sailorboy1]

Originally Posted by malbert73

Two questions:
I assume you must be the minority with a conventional battened main?
You reference a loose backstay above in #3 which I assume must be due to "backstay envy"??

I do have a no furler "conventional" mainsail. But I would trade some of that performance for the convenience of a furler rig if the price was right (I don't think all that highly of my Dutchman system).

In #3 I met a loose forestay, was able to still edit it. I don't know what backstay envy is, is it something like a foreskin?

[CarlF]

The Discovery 55 (and 58 and 67) all have B&R rigs (with backstays). By any measure, these are Water boats">blue water boats and not cheaply constructed.

There are many other B&R rigs out there - just not many on inexpensive production boats.

The B&R was designed in 1972 by Lars Bergstrom and Sven Ridder. Bergstrom also invented the winged keel (first seen on his America's cup 12 meter Australia II) as well as inventing the Windex on top of your mast.

The primary advantage of the B&R rig has nothing to do with the backstay. The swept spreaders and diagonal stays between the spreaders allow a smaller mast section. This reduces weight aloft with the attendant stability and pitching improvements. A properly designed B&R rig is also very strong with the mast staying in column better than standard rigs. Finally, you don't need an inner forestay or forward lowers to control mast pumping. This makes tacking considerably easier.

The swept back spreaders do limit how far you can push out the boom, but a high aspect mainsail pushed way out just blankets the more efficient head sails.

[skipmac]

Originally Posted by Paul L

I don't know what you consider planing. I don't consider my old J37 a planning boat, but it sure could surf for a long period. .

Planing, surfing, whatever terminology you like to indicate a condition where a sailboat significantly exceeds hull speed.

[Paul L]

Originally Posted by skipmac

Planing, surfing, whatever terminology you like to indicate a condition where a sailboat significantly exceeds hull speed.

There's a lot of distance between an ultra-light planing machine and a modern, fast cruising design.

[skipmac]

Originally Posted by Paul L

There's a lot of distance between an ultra-light planing machine and a modern, fast cruising design.

Well of course there is.

Look, I'm not trying to write a treatise on all the variations of hull design and the effects of form on performance. I simply tried to point out that the post you referred to had already stated that what malbert called a planing hull could achieve better VMG by tacking down wind.

Whatever terminology you want to use, exceeding hull speed requires some mechanism to overcome the limitations from the bow and stern waves which by my understanding will mean the boat to some degree will be going over the water as opposed to through the water. So call it planing, surfing, modern hull design or whatever.

[Paul L]

Back to the B&R rig issues, for a decently performing cruising boat there will be many cases where DDW is not the best performance.

[malbert73]

Originally Posted by Paul L

Back to the B&R rig issues, for a decently performing cruising boat there will be many cases where DDW is not the best performance.

I guess we can agree to disagree.

I just haven't ever seen evidence other than "we do better" for not sailing DDW if speed to destination is prime objective. Yes, it feels faster, but at the expense of too much extra distance.

Now for hard evidence using math:

Using trigonometry (law of cosines) you can calculate the following by sketching triangles of angles:

DDW speed angle up from DDW sailed break even speed at angle
6 10 degrees 6.1
6 20 6.4
6 30 7
6 40 7.8
6 50 9.3

assuming DDW speed wing on wing is 6 knots-

if you head up by 10 degrees, you need 6.1 knots to break even
if you head up by 20 degrees, you need 6.4 knots
if you head up by 30 degrees, you need 7 knots
if you head up by 40 degrees, you need 7.8 knots
if you head up by 50 degrees, you need 9.3 knots



The first 2 angles (10-20 degrees) are really not possible without poled or asymmetric downwind sails like spinnakers or code zeroes. The genoa will just be blanketed and unless it's a tiny jib and a huge main, the loss of sail area will preclude speed gains.
In many boats, heading up 30 degrees from DDW is the minimum needed to fill the genoa meaningfully, and up to 40 degrees is needed to derive significant speed gains. I am not sure many cruising boats will gain that much more speed sailing an angle.

This is not counting current which may add to difference.

Subjective proof is also in my observations and racing in 2 local fleets in and near Annapolis, where folks know what they are doing in non-spinnaker classes.

Every single boat races downwind wing on wing with poled out genoa on a DDW course, rather than sailing jibing angles. Occasionally someone will try to sail out on a deep reach and they always lose out. Again I believe this is because of lost effective sail area of genoa blanketed behind main. You just have to head up too much to get the genoa pulling, vs wing on wing where both sails are full.

The only boats I have ever seen race with downwind jibing angles, are spinnaker boats.


Of course, choices when cruising come down to comfort. For some boats, DDW will be more comfortable to avoid quartering waves and corkscrew motion. For others, especially in high wind condition, the risk of jibing or stuffing into a wave sailing DDW makes sailing a deep reach preferable.

I just don't think you can get there faster sailing angles unless you have an unconventional rig (huge mainsail tiny jib) or a specialized downwind sail.

[malbert73]

Also forgot to mention- if you arent using a pole on your genoa (ie it's blanketed, or flopping in and out wing on wing- then everything I have said is off the table- then any angle you sail will be faster because you're not taking advantage of the reason to sail DDW (which is having both sails draw fully)

And I assume with swept spreaders, you won't get your mainsail squared off, so you may be better sailing angles (but not as fast as if you could sail DDW efficiently).

[Paul L]

It does require that you have up enough functioning sail. You may need to pole out, but that is true going DDW also. I don' t sail DDW with the main as I don' t want to risk a jibe in seas.

[sailorboy1]

seems I can do the impossible

[Hudson Force]

Originally Posted by Paul L

.............. I don' t sail DDW with the main as I don' t want to risk a jibe in seas.

Certainly this can't be a fulltime risk. We seem to find enough light wind days when an uncontrolled gybe of the main is a refreshing sign of activity ending with a gentle surge.

[FranklinGray]

Sorry to bring a dead thread back to life but I thought I would add to the 'advantages' list by expanding on what another poster said about not worrying about pumping.

The number 1 reason the B&R rig was made was to make a lighter rig that was very sturdy. In fact, I'd go so far as to say it is the most reliable rig there is for the simple fact that it will not pump and that is what breaks masts (besides rigging failures).

Why? How? Ever hear that you aren't supposed to sail with headsail alone? That is because a traditional mast head rig genoa will cause the mast to pump due to the big loads being applied to the top of the mast but not much to stabilize the middle of the mast. This leads to metal fatigue and then breaking of mast.

The B&R rig distributes the load from the small jib (much less load normally) to the stays. The stays then push the spreaders in, but the diagonals are pulling backwards, so you end up with a push pull that stabilizes the middle of the mast where it is needed the most.

Those that put a backstay on the B&R rig are only doing it so people will not freak out about it. Fact is, if that backstay is tight, then it will actually hinder the stabilization of the middle of the mast by taking load away from the spreaders.

The pre-bend also adds to the stabilization too, preventing the mast to buckle the wrong way.

The B&R rig has a lot of problems when sailing and it's not just down wind, but strength and reliably is not one of them. I've been sailing my Hunter 376 all over the Caribbean, Gulf of Mexico and Bahamas for the past 10 years. Don't know if I would by another boat with a B&R rig but if I didn't, I would be worried about mast pumping on the standard rig.

And yes, this pumping is real. Aluminum is very susceptible to pumping. I first noticed is on a aluminum pole I had a wind generator on and it was a big strong pole. Had to change it to SS.

[Adelie]

Oh, that's nothing, I've seen 8 year old threads revived.

As far as the B&R rigs go the jury is still out on them. Yes they are in production. After several decades only the one manufacturer that I know of is producing them. Perhaps that is a patent issue, perhaps not.

As an an engineer I can say the this rig adds a lot of complexity without redundancy as far as I can tell.

Failure of a normal rig under jib alone is not a fatigue issue but one of very high loads in a minimally supported plane probably coupled with harmonic pumping. Double lowers and a "cutter" rig will deal with this at least as effectively as the B&R rig and it provide substantial redundancy.


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