Stanchion Work

[MKirk51]

I'm looking for opinions, experiences, tall tales, whatever you're kind enough to provide, about some stanchion work. My main haulout project for this year is rebedding, so I removed all the stanchions and pulpits this past fall, and will reinstall this spring. As you can see in a photo from a couple years ago, there are lots of openings in the cover for them, and they always seem to allow snow and water to get in. After sealing all those openings in the cover before installing it this year, I realized how great it would be if I could remove the stanchions and pulpits EVERY year, and eliminate those openings.
As you can see in the other photo, the bases are all welded on. I'm thinking I can cut the existing bases off and replace them with the separate bases that use either set screws or a bolt and nut to hold the stanchion on. That way I can remove the stanchions, pad the bases somehow and let the cover go right over the top of them. No leaky openings.
Whaddya think? Am I gonna lose a lot of strength by going this route? Also, I see the bases go for anywhere from about $20 (ebay) to $50 or more. I'm fresh water so I'm thinking the cheaper versions would be OK as long as they have the reinforcement rod on them. Any comments on going with the cheaper version? I've heard bad things about the metallurgy coming out of China.
Thanks for any and all comments and advice, and I hope you all enjoy the holidays and have lots of boat goodies coming your way.

 

[Ross]

If you can find some tubing with an inside diameter that will allow you to slide it over the existing tubes then all you will need is to cut the pieces to length, drill and tap four holes in each and cut your stanchions at a convenient height and telescope the pieces together. Crutch tips will serve as padding.

 

[Rich (P303)]

Take a look at Mainesails "how too"... re-bed hardware before you do ANYTHING. Basically... he enlarges the hole... takes out some core material between the glass... countersinks top surface... epoxies hole and re-drills... using butyl tape (I think) as a gasket.

I have a 1984 Pearson and I have a 2 piece set-up... the stanchion base... and the upright. Upright fits into base. I can take uprights off If need be. I have a little wobble. As long as it is attached thru... no need to worry. I would not want a captive screw that threads thru the base and bites on the upright... rather threads into the upright with just a hole in the base.

Ross's idea seems like a plan... you will have "beefy" stanchions,

My set-up seems feasible...however I haven't fallen over the side on a tether either.

 

[Roger Long]

Re: Ross' idea

Uh, don't do that. A tube slipped over another like that may not be as strong as a continuous tube of the same diameter. After the first load, like the helpful people on the dock who always try to stop your boat with the tops of the stanchions, you'll probably find that you can't get the stanchions off again either.

Stanchions are pretty important and you've got nice solid ones. I wouldn't mess just to cover the boat more convieniently in the winter.

 

[RAD]

As someone said look at Mainesail's web site on this and as a 32 ODay owner who has done this project I can say for one thing I'm pretty sure the stanchion's are unique to ODay's because of the angle so replacing with a different base might create problems and getting to the nuts can be a challenge if your headliner is fiberglass like mine and what I did was take a hole saw and find the exact location of the stanchion nuts and thats where I made a 2" hole and with a flex box wrench I was able to get the nuts, also ODay used small washers above the nuts and no backing plates so I made backing plates that slipped into the 2" openings.
Another trick I did when putting the nuts back on was to use standard nuts first cause I could use my finger to spin them on then tighten with the wrench followed by an aircraft locking type nut.

 

[Prime Time]

Stress Riser

Uh, don't do that. A tube slipped over another like that may not be as strong as a continuous tube of the same diameter. After the first load, like the helpful people on the dock who always try to stop your boat with the tops of the stanchions, you'll probably find that you can't get the stanchions off again either.

Stanchions are pretty important and you've got nice solid ones. I wouldn't mess just to cover the boat more convieniently in the winter.

It is called a "stress riser". Same reason a mast repaired with a sleeve is not as strong.

 

[kloudie1]

OK, I am completely unfamiliar with covering a boat, but it seems that it would be much easier to raise the mast mount of the tarp higher and have a skirt sewn that would cover the stanchions? Not trying to be a schmart ash but that seems like a LOT less work.. ??

 

[Maine Sail]

Re: Ross' idea

After the first load, like the helpful people on the dock who always try to stop your boat with the tops of the stanchions,

Roger you hit on one of my biggest pet peeves!! Why on earth to people feel the need to grab the absolute top of a stanchion. Launch drivers are famous for this and it's usually a stretch to reach the tops?? Grabbing lower means LESS wear and tear...

P.S. Leave your stanchions the way they are unless you can find replacement bases with the same exact hole pattern and the correct deck angle, of which there could be a couple different ones. Re-driling, filling, the cost etc. etc. are all not worth it IMHO.. Re-bed them and be done with it but don't worry you'll find plenty of other projects to suck money...

 

[Steve Dion]

If you want to have removable stanchions you may want to contact Garhauer Marine. They make semi custom part all the time. I am sure that they will custom drill the bases to match your pattern.

http://garhauermarine.com/catalog_process.cfm?cid=54

Call them and see what they can do for you. New stanchion & bases would be under $60 each. If you catch them at a boat show, the prices are even less.

 

[Ross]

My stanchion bases are short sockets ( two diameters deep) into which one inch tubing is inserted to creat a stanchion.
Someone needs to explain to me how this is substantially different from applying an external sleeve to an existing one piece stanchion that has been cut 3 inches above the base and a six inch external sleeve installed. I have been messing about machinery all of my life and I can't for the life of me see how this ; A . is weaker . or B. Creats a stress riser.

 

[Pops]

Maine Sail, one of my pet peeves is; people who pull on the life lines. I explain to people that they are very strong, well maintained, clean, and convenient. Then I try to explain, that the reason they are like that is, because they are there to save their lives (and no other purpose). I can't even imagine what I would do if someone pulled or pushed on one of my stanchions. (Drinking beer and wrapping presents, Merry Holidays! Thanx for your Presence on this site.)

 

[higgs]

Maine Sail, one of my pet peeves is; people who pull on the life lines. I explain to people that they are very strong, well maintained, clean, and convenient. Then I try to explain, that the reason they are like that is, because they are there to save their lives (and no other purpose). I can't even imagine what I would do if someone pulled or pushed on one of my stanchions. (Drinking beer and wrapping presents, Merry Holidays! Thanx for your Presence on this site.)

Maybe I am misunderstanding this post, but if life lines and stanchions cannot survive being pulled on while one is going forward, what good will they be when a real test comes along?

 

[Roger Long]

Maybe I am misunderstanding this post, but if life lines and stanchions cannot survive being pulled on while one is going forward, what good will they be when a real test comes along?

In an ideal world, they would be. However, the fact is that they are not strong enough on most production and even most custom boats. If a lifeline saves your life but bends and/or cracks the deck in the process, it has still done it's job. The repeated stresses on the highly leveraged bases and supporting structure can weaken them through fatigue and breaking of the water seal. These are safety equipment. They should be exposed to as little wear and tear as possible until needed. You might not notice any weakening or damage until you fall against them in a situation where you need them to stay on board.

Using the lifelines as handholds when on board is one thing. Standing on a dock and stopping the full weight and inertia of a moving boat by bracing yourself against the top or the wire is another. Lifelines strong enough to be used that way could be built but they would be quite noticably heavy and expensive. It's a tough engineering problem with so much leverage on such a small base and typical deck structure underneath.

 

[Rich (P303)]

I think it makes no difference Ross... I have the same set-up. MKirk probably has 1'" tubing... so if he leaves a 2" tall stub... his stanchions will have to be thicker to slide over the existing... and maybe stronger? He might want to rethink the backing plate too while its all apart. Getting the caps and middle hardware for the life lines could be interesting.

 

[sailingdog]

When you try stopping a 12,000 lb boat by grabbing a 1" diameter stainless steel stanchion that is 24" high and has a base of about 2-3" wide... you're putting a lot of torque on the base, and the chances of ripping the base out or weakening it very badly is pretty high. They're not designed for it, nor can most handle it. One acquaintance's boat is a steel one and the stanchions are 2" diameter pipe welded to the deck and connected by more steel pipe... this can take that kind of abuse... the ones on most fiberglass boats can not.

Maybe I am misunderstanding this post, but if life lines and stanchions cannot survive being pulled on while one is going forward, what good will they be when a real test comes along?

 

[Roger Long]

I think it makes no difference Ross...

Please, don't encourage him to make an expensive screw up. The larger diameter tubing will be stiffer so more than designed stress will be concentrated at the bottom. Ideally, and in most cases, the stanchion will bend and still be something to keep you connected to the boat even bent 30 - 40 degrees. In this case, it will probably break off the bottom stub. The slight slack necessary to be able to get the stanchions on and off or, due to manufacturing tolerances, will concentrate the stresses at the corner contact edges in a way that will tend to turn the tubes into ovals. Then, the kludgy looking things won't come apart.

A heavy stanchion base with a socket designed for the tubing to go into is a different proposition but most of the ones I've seen either rely on small set screws or have objectionable play. It would probably cost more to replace all the bases with those than to modify the cover.

I don't think you will find tubing that telescopes to the exact tolerances needed anyway without some expensive and weakening machining. If he does, the first time one is strained, it's probably going to oval enough that he won't be able to get it apart.

 

[Roger Long]

Someone needs to explain to me how this is substantially different from applying an external sleeve to an existing one piece stanchion that has been cut 3 inches above the base and a six inch external sleeve installed.

Those sockets are substantially stronger than the the tubing. The tubing can flex evenly along it's full length instead of suddenly meeting a point close to the maximum stress where it's strength and stiffness drop off dramatically in an almost infinitely small distance. Ask me how I know. The rudder fell off the first boat I designed.

Your stanchions are not quite as strong as they would be with welded bases anyway due to local stresses at the corner of the socket on the compression side. The strength of a structure like this comes from the opposing tension and compression on the surfaces in the up and down direction (in the case of a stanchon). The socket base turns the stresses 90 degrees in a short distance. That is always accompanied by different strains. Think of the tube just dimpling at the corner of the socket.

A socketed stanchion can be perfectly strong enough if it is planned for. The slip over tube idea may even be strong enough for the use it actually encounters. It is not going to be as strong however and stanchions are never strong enough for every eventuality. Why weaken them just to put a winter cover on?

 

[BobM]

What about just sistering the tubing to the stanchions so that the stress is more at the base? You could even use slightly angled fittings at the top of the stanchions. By the way, a really cheap source of a lot of tubing is to contact your local well service company. They pulled 200 feet of 1" pvc out of my well that had been installed in 20 or so foot sections and replaced it with a single length. They said they do it all the time and now leave it with the well's owner to discard. I gave it to a friend who has greenhouses.

 

[Pops]

Roger, I am going to print this thread and frame it on my boat. For years I have been exposed to ridicule by my crew when I attempt to explain the principles of leverage and the forces acting on the stanchion bases. I've tried to explain that every time a lifeline is used for something other than saving their life it takes some of the strength out of the system. I try to explain that the lifeline/stanchion system is like a team, each member needs to contribute to achieve the goal and the weakest member can bring the whole group to its level. I tell them that if, in an emergency, they were stopping a fall overboard, they could very well rip several stanchions off the deck and that the destruction will be absorbing their energy (energy moving in the wrong direction), slowing and then stopping them. I explain that the stronger each component is, the more energy it will absorb. By now, they are all laughing hysterically. In the future, I'll be able to smack them with this thread in a frame.

 

[Ron20324]

Beneteau uses a deck mount that has a 2 or 3-inch stub sticking up with a one-inch stanchion that slips over it. A hole in the stanchion allows a bolt to be threaded into that stub. Not the best arrangement, but I figure, hey, if they built it that way...

Like the storm that passed over Cuba and did 50 million dollars of improvements, somehow a beam stanchion got bent outwards- maybe at the dock. The stanchions are perpendicular to the angled deck, which means the stanchion top is outboard of the toe rail and bangs the pilings and other boats in a raftup. Not good. On a whim, I moved the outward-bent starboard stanchion over to the port side where it now bends inward, inside of the toe rail. So, I now have a new stanchion in hand and will take all four to the shop and have them bent half as far (one inch) as the damaged one. With this move, the lifeline will run inboard of the shroud which should provide some extra support if the lifeline goes outward when someone is on it. Yes, it's nice to be able to easily remove the stanchions for my cover, but, Matt, that's alot of work for you.