safety rail stanchion failure Catalina 28

[jansan]

Thought it might be of interest to Catalina owners to describe recent events.

Boat is on the hard during winter months in a sheltered boatyard, with a clear tarpaulin cover to let what sunshine there might be IN, and to keep the rain and snow (of which there is plenty )OUT.

Last week after a particularly strong gale I was at the yard just to check things over.

The two portside safety rail stanchions ( along from the pushpit) were bent over touching the cabin roof. These two stanchions had previously given trouble as being prone to leak under certain weather conditions.

Having eventually found a way to get them off ( !! ) it was found that the two main 1/2 inch bolts ( which give the stanchions their strength) had sheared/detached from the base plates. The shank of the bolt appears to have been simply butt welded to the plates ( not having the head beyond the plate and then welded )

Up until this event it was not obvious that these stanchions had failed.

My guess is that these bolts must have failed prior to the recent gale. in which case I`m rather glad I didn`t have occasion to test them for real when out at sea.

Replacements now ordered and I am comforted by the fact that the new stanchions are now claimed to be stronger than those which they are replacing.

However I am left wondering about the inherent strength of the design.

 

[Stu Jackson]

However I am left wondering about the inherent strength of the design.

I'm never quite sure why they call them "lifelines" because after replacing a few of them, I wouldn't trust their strength to save me from going over the side if I hit a "lifeline." Three or four 1/4 inch bolts with a lever arm of from 24" to 36" just isn't gonna do it.

Was your tarp hanging over the "lifelines?" Strong winds and snow have been reported to bend stanchions.

 

[jansan]

stanchion strength issue

However I am left wondering about the inherent strength of the design.

I'm never quite sure why they call them "lifelines" because after replacing a few of them, I wouldn't trust their strength to save me from going over the side if I hit a "lifeline." Three or four 1/4 inch bolts with a lever arm of from 24" to 36" just isn't gonna do it.

Was your tarp hanging over the "lifelines?" Strong winds and snow have been reported to bend stanchions.

Yes the tarp overlapped the lifeline/stanchions and I understand that the wind was broadside on that particular day. There was no damage to the tarp however ! The next stanchion along towards the pulpit (which is a single stanchion) was OK. This particular stanchion had never shown evidence of leaking.

I`m now wondering if there has been corrosion occuring between the mounting plates and the large retaining bolts of these two stanchions due to water ingress over the last few years. The point of fracture however is fairly clean on both bolts so I`m not too sure why they failed if that wasn`t the case.

Stu ------- did you replace your stachions because of damage or for other reasons ?

 

[mortyd]

how old is your boat? stainless means it STAINS LESS, not that it's impervious to corrosion. it's a good idea to test your stanchions and lifelines occasionally, and stu the lifelines sure beat nothing there, especially for making way around the boat; shock loading can be another story.

 

[Stu Jackson]

morty, I wasn't commenting on the usefulness of lifelines, only that they are incorrectly named. I like ours!

jansan - I replaced two of them because some bozo hit us between races one fine afternoon. You have to understand stainless and corrosion, too long to get into here, but they do fail, the bolts that is.

 

[FastOlson]

Adding back the missing Safety

While the boat is on the hard you now have a decent opportunity to upgrade the stanchion scheme to something actually usable. Note that the builder did the same minimal setup that everyone else in the production boat industry does, so no slam on Catalina.

Several years ago I dealt with several bent stanchions down both sides of our boat and also the gate stanchion on each side. After straightening, I double-braced the gate(s) and also added 90 degree braces to all of the center stanchions. I was removing and rebedding all of them anyway, so it was the right time to upgrade them.

It has made a world of difference in safety and usefulness.
I have some photos in a thread over at the Ericson site. Link: http://www.ericsonyachts.org/infoexchange/showthread.php?3371-Stanchion-Bracing&referrerid=28

All these years you have probably been cautioning crew and visitors not to grab or pull hard on those posts and wires on both sides of your boat... and cringing/sighing when they later ask you why you refer to them as "Lifelines."
It doesn't have to be that way.

LB

ps: each of our bases has five bolts.

 

[mortyd]

Re: Adding back the missing Safety

as an engineer i will say if you strengthen the stanchions enough and they are subject to loads great enough, they will just pull out of the fiberglass - perfectly intact.

 

[jrowan]

While the boat is on the hard you now have a decent opportunity to upgrade the stanchion scheme to something actually usable. Note that the builder did the same minimal setup that everyone else in the production boat industry does, so no slam on Catalina.

Several years ago I dealt with several bent stanchions down both sides of our boat and also the gate stanchion on each side. After straightening, I double-braced the gate(s) and also added 90 degree braces to all of the center stanchions. I was removing and rebedding all of them anyway, so it was the right time to upgrade them.

It has made a world of difference in safety and usefulness.
I have some photos in a thread over at the Ericson site. Link: http://www.ericsonyachts.org/infoexchange/showthread.php?3371-Stanchion-Bracing&referrerid=28

All these years you have probably been cautioning crew and visitors not to grab or pull hard on those posts and wires on both sides of your boat... and cringing/sighing when they later ask you why you refer to them as "Lifelines."
It doesn't have to be that way.

LB

ps: each of our bases has five bolts.

Say, I was wondering what method U used to "straighten" your stanchions. I also have a couple of stanchions that have been slightly bent by a P.O. that I would like to strengthen without damaging or weakening further. Thanks.

 

[FastOlson]

Say, I was wondering what method U used to "straighten" your stanchions. I also have a couple of stanchions that have been slightly bent by a P.O. that I would like to strengthen without damaging or weakening further. Thanks.

Not wanting to chance a kink, I took them to a local marine ss fabricator. He had a hydraulic press with the proper size mandrels. Ours had not stretched the metal so far that it wrinkled when straightened, either.
Then he mirror-polished all the stanchions and pulpits. Visually awesome!
The real and lasting change, tho, was the bracing for all the midship stanchions and the two-way brace for the gate stanchions.

Worth noting is that a talented fabricator can cut out any badly-bent section and put back a straight piece. Once polished out, the repair is invisible! He did this to fix one bent section of our bow pulpit, courtesy of the prior owner.

Since that upgrade, you can grab that braced gate and lever yourself aboard. No harm to the boat or to you. Much much safer.

L

 

[mortyd]

the repair may be invisible, but once metal has yielded(bent) it has probably lost signicant strength.