No backstay on the 26M??

[NiceAft]

A I A

[Oskar 26M]

The PO of my 2007 was a blue-water buff, and said felt "unsafe" in the relatively strong-wind sailing conditions here in the west of Oz with the standard rigging. So he beefed it up a lot, with stronger rigging generally and also added a backstay. He didn't like the rotating mast idea either, so he welded the mast to a fixed position. Then he (or perhaps his admiral) decided he that the 's tender behaviour was not what was wanted. They sold their boat to me so they could go and build a 45ft cat.

As a result Oskar has a proper running backstay, tougher overall rigging and no rotating mast. Since I've never experienced the original rigging, it a bit hard to comment on benefits or otherwise of modified versus original rigging, but I must admit that I quite like the security of a true backstay in our sailing conditions and also like the sail trim improvements a backstay offers in a fractional rig. But I suppose I dont know what I'm missing by not having a rotating mast...

[ronacarme]

I understand the M mast is fixed against falling forward by locating the shroud bases aft of the mast base, and using swept back spreaders for the uppers. Such a backstay-less, "tripod " arrangement of forestay and shrouds, as the mast support, is common in many sailboats, ranging from small sailing dinghies up. See also one or more of the big Hunters (wherein ommision of a backstay allows enlarging the area of the mainsail by adding a large roach, as on many racing and cruising catamarans). See also the lack of a backstay on most trailerable cruising sailboats, including most if not all Ventures and Macs from their beginnings in the late '60's up to and including my old 26D and present 26X. The X's backstay is not needed for mast support (the backstay on mine is usually slack), but can be tightened to bend the upper part of the mast aft, to flatten the mainsail and thus depower it for sailing to windward in higher winds, thereby reducing heeling and delaying somewhat the need to reef the main. Ron

[Kelly Hanson East]

So he beefed it up a lot

Ive seen quite a few posts about this lately and I hope people/POs/ are thinking adn executing this through carefully.

You cant just make rigging 'stronger' by going up in size. When standing rigging wire size (diameter) goes up, so does the tension needed to remove the stretch in the rigging. Even going from 1/4 inch to the next size of 5/32 will mean you will have to tension increase from about 300# to 500# (refer to Loos gauge tension table) to properly tension the new wire....Roger's boats are engineered fine for intended use, but there is not tons of margin in the hull design and I doubt I would want to tension my forestay to 500# without strengthening the forestay plate.

You cant just run the thicker rigging at the lower tension, since then you will be shock loading it, and all bets of safety are off.

I think Moe has pointed this out before, to give due credit, but it is worth repeating.

[Paul L]

engineering isnt a touchy feely science - its crunching numbers and understanding materials strengths and strains

I agree 100%. Thanks for all the feedback and comments. I bow to the wealth of knowledge and experience here.

When I cranked up the mast for the first time a few days ago, of course I'm on the foredeck, and not in a position to appreciate the aftward sweep of the spreaders.

However, as I said in my first post, I've done a lot of guyed radio tower work in my career (building and climbing) and I would be hesitant to climb a tower with guy wires so close to the base.

I am sure that you are absolutely right: Roger and his enginners know what they are doing. The fact that this subject is a non-issue, is testament to that.

[baldbaby2000]

See also the lack of a backstay on most trailerable cruising sailboats, including most if not all Ventures and Macs from their beginnings in the late '60's up to and including my old 26D and present 26X.

Actually all the old Ventures and Macs I've seen before the 26 had backstays; my Mac 25 did.

[baldbaby2000]

However, as I said in my first post, I've done a lot of guyed radio tower work in my career (building and climbing) and I would be hesitant to climb a tower with guy wires so close to the base.

I used to climb towers too and never did get over my fear of heights. The worst ones were the 60 foot non-guyed towers; they'd sway back and forth while I was working on an antenna! They were scarier than the 350 foot guyed tower I climbed.

[Kelly Hanson East]

A I A

AATF = Apologies After the Fact

AIA = Apologies In Advance



(there is a great website of txt abbreviations at www.netlingo.com if you want to try and keep up with your teenager)

[Terry]

So he beefed it up a lot

Ive seen quite a few posts about this lately and I hope people/POs/ are thinking adn executing this through carefully.

You cant just make rigging 'stronger' by going up in size. When standing rigging wire size (diameter) goes up, so does the tension needed to remove the stretch in the rigging. Even going from 1/4 inch to the next size of 5/32 will mean you will have to tension increase from about 300# to 500# (refer to Loos gauge tension table) to properly tension the new wire....Roger's boats are engineered fine for intended use, but there is not tons of margin in the hull design and I doubt I would want to tension my forestay to 500# without strengthening the forestay plate.
You cant just run the thicker rigging at the lower tension, since then you will be shock loading it, and all bets of safety are off.

I think Moe has pointed this out before, to give due credit, but it is worth repeating.

Stephen,
The shrouds on the M are 5/32, only the forestay is smaller. I had to increase my forestay to 5/32 to accommodate a Schaefer Snapfurler. When I went to a rig shop to have it done the rigger asked me if I'd rather just buy a whole new forestay than just change the wire. He then showed me the next size up turnbuckle which was 5/16. One look convinced me to replace the whole forestay so now I have the oem for a spare. I really only needed to upgrade the wire but for a few more $ I felt it was worth it to have a more substantial turnbuckle as well. You'd have to see them side by side to appreciate the difference. Certainly it takes a bit more load but it is highly unlikely you need to strengthen the foretang or forestay plate as it is quite substantial already. Keep in mind you have four big 5/32 bullies fighting with that scrawnny little 1/4 turnbuckle and 1/8 wire (not 1/4 wire), not a fair fight in my opinion.
The problems Leon (delevi) experienced come to mind readily! The oem forestay is marginal at best, and I would not trust it with the added load of a rollerfurler. It did work fine for 5 seasons with hank-on sails though and I only bent the lower thread bolt on the turnbuckle once through overtightening.
The rest of the rig is fine for the boat it is on but I think if I were in Oskars boat I'd replace my mast plate with an oem that turns and deep six that welded one.

[bscott]

Terry X 2, also add that the mast is 2' longer and heavier.

Bob

[delevi]

My oem forestay didn't fail. It was the turbuckle that failed. The casue may have been my tensioning it under full load. 5/32" wire has a breaking strength of 3300 lbs. Static loads should be 15% per most rigers' recommendations and can go up to 20% on a swept spreader, backstayless mast such as the rig. Mine are set at 17% on the uppers and about 10% on the lowers. So what are we talking about here? I don't have a single recollection of a post on this board about rig failure that didn't involve an accident, operator error, or other extreneous circumastances.

Leon

[Kelly Hanson East]

Terry - thanks for catching my bad.

Forestay 1/8 of course, not 1/4

The forestay plate is pretty decent and, more importantly, is easier to inspect for 'looseness' than then X

If I calculate this right, you would need 500 pounds of tension in your forestay minimum, which of course raises your shroud tension by some amount (although you can adjust it with your turnbuckle unlike the stock )

Where are your shroud tensions running with the forestay at 500#??

I know what you mean when you pick up a good piece of hardware and know that it is better suited for a job..

[Terry]

My oem forestay didn't fail. It was the turbuckle that failed. The casue may have been my tensioning it under full load. 5/32" wire has a breaking strength of 3300 lbs. Static loads should be 15% per most rigers' recommendations and can go up to 20% on a swept spreader, backstayless mast such as the rig. Mine are set at 17% on the uppers and about 10% on the lowers. So what are we talking about here? I don't have a single recollection of a post on this board about rig failure that didn't involve an accident, operator error, or other extreneous circumastances.

Leon

Justification for rigging upgrades
"That's what I'm Talkin about"

Stephen'
The upgraded forestay does indeed put more strain on the shrouds, not to mention the difficulty it adds to pinning the forestay with the added tension. It took me a bit more work getting the rig tuned with adequate tension on the shrouds but I eventually got it done. Now it is set but I will confess pinning the forestay takes abit tighter winding with the mast raise crank but also the roller furler makes it difficult to get my fingers around the end of that turnbuckle, not a lot of room to work with. I slip for the season so I do not have to do it often.

[Hardcrab]

There was a forestay failure that I have personally seen at MDR.
There was discussion here at the time.
The forestay broke at the "loop" at the upper (of the two) NicoPress fittings up on the mast hound.
All strands of the loop itself broke open and the thimble remained on the mast hound.
The winds were somewhat heavy (for MDR) at 15-18 kts.
I don't remember if it was a hank-on or a roller furler.
The mast came down aft and to the starboard side, as they were sailing on a port tack.
No one was injured, although a spreader came into the cockpit in a place that could have speared someone if present, and damage was minor.
I did not see any obvious reason as to what caused the wire to break.

As a result and because I keep my boat in the mast-up lot, (mast raised 24/7/365) I now lower the mast and inspect all shrouds every six months.

[Hamin' X]

There was a forestay failure that I have personally seen at MDR.
There was discussion here at the time.

The discussion of this incident can be found here:

Dismasted Under Sail! Hate it when that happens . . . .

~Rich