Any suggestions for a flag halyard on the wishboom of my 22? I have a sheeve 41 near the top of my mask, but that’s a lot of line to be just hanging around rarely used. Looking for ideas on how I could rig something from my wish book when needed.
John Gialanella
Tourmaline, NS22
Bolles Harbor, Michigan
On my 26 I have a small block attached by a pad eye to the starboard side of the boom near the mast. I have a continuous loop run through the block that I tie off on the pulpit. I have about 6’ of bungee in the loop to allow for stretching as the boom swings from one tack to the other.
I also have the cheek block on the port side at the top of the mast. I have a light messenger line running through that block so I can run an emergency halyard if necessary. The messenger line is always in place so I can use it for burgees if I want.
Mark Powers
Thanks Mark.
I have that cheek block at the top of my mast as well. It seems too small to use as a spare halyard however. Your take?
Johnny,
The Nonsuch 26 manual says the working load for its burgee halyard block should be 500 lbs. min.
[Update: I typed this in error – the actual specification is 1000 lbs.]
That’s [still close to] the bare minimum I’d personally consider safe to use for taking someone up the mast, and would use it only in an emergency where there was no alternative. I don’t think it would serve as the block to use for a replacement or backup halyard for sailing purposes, both because of its limited strength and poor positioning for that use. [Correction: strength might be ok, but positioning on the side of the mast is problematic.]
I just did a quick scan of the N22 manual, and could not find a list of specifications for blocks.
I happen to know that the INA suggests N22 owners follow the recommendations for N26s when replacing blocks. (The reason I know is that I was the one who wrote that recommendation.)
That advice is based only on the reasoning that this will at worst lead to slightly oversizing any block replacements on an N22. This might add unnecessary cost, but is oversizing is safer than undersizing. It’s the best the INA could suggest given the lack of any N22-specific information.
This does not mean that your N22 has a 500 lb [or any other] working load burgee halyard block. It simply means that [1000 lbs.] is the recommended replacement. There doesn’t appear to be any available information about the specifications for the blocks that were original equipment for the N22s.
– Bob
When I look at the manual for the 26C it states the max working load for the burgee halyard is 1000 lbs. Am I misreading? It also indicates the working load for the blooper is 1150 lbs. I can’t find the reference but I recall reading in the last few days that the burgee cheek block could be used for an emergency halyard. I suspect the emphasis is on emergency. I use it as a safety back up when going up the mast. Interesting point is that the block is rated at 1000 lbs but according to my calculations the four machine screws holding it in place only have about 800 lbs of sheer load. I came across a question and response from the December 1994 Update article, page 5, on the use of the block on a 22 for taking a person up the mast. The response from the “Access” group said it was designed to be sized for that purpose but they did not believe the mast cheek block was built to the specs.
Mark,
You’re right about the specified 1000 lb. working load for the burgee block. I don’t know where or how I came up with 500 lbs as the number. I seem to be making more and more mistakes like that lately.
– Bob
Bob, if I don’t make at least two mistakes in a response I figure I am having a good day.
Mark
Shear strength of the fasteners is critical and usually overlooked. If the block fails it may still hold up the line, depending upon exactly how it fails. (Bearings, sheave, etc.) It may not operate, but what’s left of it might still prevent you from falling to your death. But if a fastener fails, the remaining ones are suddenly under much greater stress and are also likely to fail, resulting in the block coming down. And the next size up on the fasteners will bring a big increase in shear as long as the holes in the block are large enough to accept them.
And it looks like I used the wrong “sheer” I ought to have use “shear”.
Mark
As have I, even after who knows how many thousands of times I’ve typed it correctly. My excuse: this is more conversational than technical. 
I type really fast and my most worn out key is the backspace. Everyone here has already seen the error, and probably many others that I’ve missed. The beauty of Discourse is that we can go back and correct it, which I’ll probably do just so it reads correctly for posterity. Don’t want people thinking we are talking about semi-transparent screws.
I suppose if the bolts are sheer the shear strength would be low and it would not be safe to rely on them for mast climbing.
One of the things I really like about Discourse is the ability to go back and edit posts. Over time, it’ll make these threads more useful for people going back later. We can cut down on the amount of misinformation that gets circulated.
For example, I just went back and edited my post about the working load for the block that started this discussion. Under other circumstances, I would’ve just rewritten it to eliminate my mistake, but since the discussion following wouldn’t make sense, I edited to ‘fess up to it.
My search engine’s AI summarizer claimed that the shear strength of a #10 316 stainless machine bolt was a number I have trouble believing, but I have trouble thinking that the weight of a person could shear four of them.
– Bob
I can’t imagine the static weight of a person shearing four #10 screws. If the burgee halyard is used as a safety line when the person is up the mast, then maybe the shock load from a fall could be enough to shear them. Depends in part on how far you fall before the line catches you and on what the safety line is made of. So keeping the safety line tight - and making it from nice, stretchy nylon - will significantly reduce the shock load on the block and the screws.