Removing the backstay on a 1990 B&R Rig

smokey73 · Apr 3, 2020

I know that the rig will stand when you remove the backstay because they used to have to do that when they hauled my boat for work because of the way the travel lift was configured. However, I don't know if the attachments for the shrouds on your boat were designed to take all of the load since they put on a backstay too. On mine, the shrouds connect to a solid rod that goes from the deck all the way to a point on the bottom of the hull. It looks pretty stout. It may also be that it was early in the process for Hunter using B&R rigs and they want'ed some insurance. I like the idea of a backstay. Why do you want to ditch it?

chuckwayne · Apr 3, 2020

Earlier B&R rigs used by Hunter had a backstay that was an integral part of the design. Later, I think starting around 2000, the rig was designed to be backstayless. This change included swept-back shrouds to carry the load and a beefier mast section. If your boat doesn't have these key features I wouldn't remove the backstay without consulting with an expert in B&R rigs.

kloudie1 · Apr 3, 2020

The later rigs without a back stay have longer, stronger spreaders i don’t think you can safely remove the back stay.

Ralph Johnstone · Apr 4, 2020

Any way to measure how far the shroud attachments to the deck are aft of the mast. It's difficult from the photos to see how much the spreaders are swept aft. Mine seem to be much further aft than yours.

Steverhnm said:
this boat was raced in So CA before I owned it. I am wondering if it has the backstay for that reason.

The other question would be "is the backstay factory installed" or just a slap-on by the previous owner ?

Either way, I would tend to err on the side of caution without an expert opinion from a rigger.

Ralph Johnstone · Apr 4, 2020

OUCH ! ! !

With the nice little pedestal for the backstay mount, it's definitely a factory installation.

Looks like you're stuck with it.

lemoiney · Apr 4, 2020

Agreed, it’s factory original. The base mount shows that. This is not a B&R rig as the spreaders are not swept back to 35 degrees each or long enough. Back stay is a must in this rig. The fact that it’s adjustable is something you can change by getting rid of the rope and tackle and pre-tension the back stay to your preference. That’s one less line on the stern if that’s what you are looking for. Lots of biminis are cut for back stays with a 5-6” sock sewn in around them as the back stay exits the top and are tied off with a short lanyard to limit water running down the wire and into the cockpit. You might need to shorten the split stays at the back to get the proper tension with the turnbuckles when you remove the adjustment tackle. Easy to do or measure and take them to your nearest chandlery and they can shorten them for you. Good luck.

Neffilicious · Apr 4, 2020

lemoiney said:
Agreed, it’s factory original. The base mount shows that. This is not a B&R rig as the spreaders are not swept back to 35 degrees each or long enough.

Actually, it IS a B&R rig and the back stay is factory as others have said. I had a ‘94 33.5 with the exact same rig and it stated in the owners manual to be B&R. My “90 Passage 42 is in the same config, and is also B&R. The rig was changed mid-90’s as you describe to eliminate the back stay.

shawanaga · Apr 11, 2020

I have the same year this is definitely not a B&R rig. It has swept back spreaders but not nearly as much as a B&R rig Also you would have the separate stays between the two upper spreaders
I wouldn’t take that back stay off it gives you support down wind

DrJudyB · Apr 11, 2020

Your rig is missing reverse diagonals intermediate shrouds, labeled 1 in the diagram below. Without the reverse diagonals it’s not a B&R rig designed to go without a backstay.

Calif. Ted · Apr 11, 2020

The Hunter docked next to me sans backstay also has 2 rigid "mast struts" (best guess) between cabin top and the mast at gooseneck level, don't know if that's common to all the stayless boats.

smokey73 · Apr 11, 2020

DrJudyB said:
Your rig is missing reverse diagonals intermediate shrouds. Not a B&R rig.

Interesting. As I understand it, there is a "Generation 1 B&R rig" that used a backstay. Later, improvements were made in supporting the mast, probably including the reverse diagonals and more sweptback spreaders that allowed them to remove the backstay, although I don't know what was specifically done to allow removal of the backstay. Perhaps what we have on the Hunters of the early and mid 90s with swept back spreaders, no reverse diagonals, and the backstay is a Gen 1 B&R. In that case, the backstay is an integral part of the design and not to be removed.

My 1994 Hunter 40.5 factory drawing shows the top spreader to be swept back by 22 degrees and the lower spreader to be swept back by 21 degrees. I'm not sure how that relates to a Gen 2 or Gen 3 B&R rig. Does anyone know what the sweep back angle of the spreaders is for a B&R rig. My mast will stand without the backstay but I wouldn't want to sail without it. My original 40.5 brochure says "sweptback spreaders" but does not specifically say it is a B&R rig.

smokey73 · Apr 11, 2020

Doing a little more research, it looks like the spreaders on a B&R rig is more like 30 degrees rather than the 22 degrees on my 40.5.

Interestingly, the early Passage 42 brochure shows a backstay but says its a B&R rig. Looking at yachtworld pictures of a Passage 42 it shows the reverse diagonals but still has a backstay so just surmising it is a Generation 1 B&R. Spreaders look like they are swept back more than my Hunter 40.5

B&R rig - Wikipedia

en.wikipedia.org

The B&R Rig - boats.com

Swept-back spreaders prebend the mast and eliminate the need for backstays

www.boats.com

Cruising World

books.google.com

Ed Caldwell · Apr 11, 2020

Calif. Ted said:
The Hunter docked next to me sans backstay also has 2 rigid "mast struts" (best guess) between cabin top and the mast at gooseneck level, don't know if that's common to all the stayless boats.
View attachment 177404

No, those are not "required" due to lack of a backstay. Those struts are to stabilize the lower 1/3 of the mast cross section on Hunters of certain size and years without in-mast furling. For instance my H340, 1999 model, B&R without a back stay and standard rig has them. The same year boat with in-mast furling has a larger mast cross section and does not need the struts.

sailor832 · Apr 14, 2020

courtesy of Wikipedia
B&R rig
From Wikipedia, the free encyclopedia

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A variant of the Bermuda sailboat rig

Characteristics of the B&R rig include swept spreaders (2) and reverse-diagonal shrouds (1).
The B&R rig is a variant of the Bermuda sailboat rig, designed and patented by Swedish aeronautical engineers Lars Bergström and Sven Ridder.[1] It employs swept spreaders that are usually angled aft, together with "stays" running diagonally downward from the tip of the spreaders to the attachment of the next pair of spreaders to the mast or to the intersection of the mast with the deck (so-called reverse-diagonal shrouds) that facilitates a pre-bend of the mast (curving aft) that is sometimes tuned into the rig before it is stepped onto the boat. Conventional shrouds thereby contribute to both lateral and longitudinal stability, unlike rigs with unswept spreaders.[2] A B&R rig can be a masthead or fractional rig depending on how stays are configured;[3] a backstay is optional.[4] Such rigs are employed in many of the models of at least one U.S. manufacture and in many thousands of boats, worldwide.[4][5]
Contents

History[edit]
The earliest B&R rig was the result of wind tunnel tests and research by Lars Bergstrom and Sven Ridder at Sweden's Royal Institute of Technology.[6] The first generation, built around 1970, included a backstay and was used on many production boats. A patent application for the B&R rig was submitted in 1973 and was granted in 1975.[1] A second generation eliminated the backstay but used solid, deck-mounted struts to brace the lower mast section. In 1982 a second generation B&R rig with 2 forestays was incorporated into the 60 ft (18.3 m) "breakthrough" racing yacht Thursday's Child. On February 13, 1989 Thursday's Child beat the 135 year old clipper ship record sailing 15,000 mi (24,140 km) from New York to San Francisco.[7] A third generation B&R rig mounted the mast on a tripod of struts, had a single forestay and no backstay. In 1993 the third generation was incorporated into the all carbon/kevlar 68 ft (20.7 m) yacht Route 66.[6][8][9][10] The 60 ft (18.3 m) yacht Hunter's Child finished 2nd in the 1994-95 BOC Challenge using a 2nd Generation B&R rig. By 1997 more than 10,000 production sailboats were using the B&R rig.[4][11]
Tuning[edit]
Part of the design of the B&R rig involves inducing a "pre-bend" in the mast which provides some of the side-to-side and fore-and-aft stability of the rig.[2][3][4] The pre-bend is achieved by tensioning the reverse diagonals and certain other so called intermediate shrouds. Because the spreaders are swept back at approximately a 25° to 30° angle, this tensioning bows the mast. Balanced and proper tensioning keeps the bow in the mast in the fore-aft direction and eliminates any curvature in the sideways direction. The pre-bend is generally set up on the ground before the mast is stepped (placed onto the boat). The mast is then stepped and all other standing rigging is attached to the boat and properly tensioned.[4][6][12]
Boat and yacht models incorporating B&R rigs[edit]
The majority of Hunter Marine's fleet incorporated the B&R rig. However, manufacturers on both sides of the Atlantic Ocean have employed B&R rigs in their boat designs.

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Models with 1st Generation B&R rigs

Boatbuilder	Model	1st Year Produced	Last Year Produced	Ref
Hunter Marine	31	1983	1987
Hunter Marine	34	late 1982	1987	[4][13]
Hunter Marine	Passage 42	1989	1998	[14][15]
AB Radab	Windex 92	1981	1991	[16]

hide
Models with 2nd Generation B&R rigs

Boatbuilder	Model	1st Year Produced	Last Year Produced	Ref
Hunter Marine	420	1998	2004	[17][18]
Hunter Marine	Passage 450	1996		[4]
Hurley Marine Ltd. (UK)	Tailwind 38	1973	1974	[19]
Torkel Batar (Sweden)	B&R 23	1993	-	[20]

hide
Models with 3rd Generation B&R rigs

Boatbuilder	Model	1st Year Produced	Last Year Produced	Ref
Goetz Custom Sailboats	Route 66	1993		[4]

Removing the backstay on a 1990 B&R Rig

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