C27 Replacement Spreader Bracket

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Ajay73

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Jun 11, 2011
253
Catalina 1980 C27 Meinke Marina on Lake Erie
Wondering how many out there replace the stock C27 spreader bracket with the stainless steel one available from Catalina Direct? The claim is that the stock, cast aluminum bracket may fail suddenly. To me the pressure on the bracket is primarily inward and the bracket just holds the spreader in place. There wouldn't seem to be much lever arm on the bracket itself. Any opinions out there?
 
May 6, 2012
303
Hunter 28.5 Jordan, ON
It doesn't take much lever arm to crack the base of the spreader receiver, and, what about the tangs that the lowers are attached to?

I'd make the upgrade.
 

mortyd

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Dec 11, 2004
952
Catalina 30 easy living
get the proper one from catalina yachts; if your'e particularly afraid of aluminum avoid commercial airplanes.
 
May 6, 2012
303
Hunter 28.5 Jordan, ON
mortyd said:
get the proper one from catalina yachts; if your'e particularly afraid of aluminum avoid commercial airplanes.
If commercial airplanes were cast in like fashion I'd avoid them too.

Fortunately they aren't.
 

mortyd

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Dec 11, 2004
952
Catalina 30 easy living
are you referring to hunter parts or the many catalina spreaders you've seen that failed?
 
May 6, 2012
303
Hunter 28.5 Jordan, ON
mortyd said:
are you referring to hunter parts or the many catalina spreaders you've seen that failed?
The subject of the thread. Please do try to keep up.
 

mortyd

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Dec 11, 2004
952
Catalina 30 easy living
the question was comparing two specific parts; how does your answer stick to the topic? exactly which of the two do you prefer, why, and where is this in your reply.
 
Dec 11, 2008
1,338
catalina C27 stillwater
Wow.

Someone is cranky this morning....

Ajay, I haved replaced the stock cast aluminum with the newer stainless spreader brackets. In discussions with several sources including the Catalina plant the recommendation is to do the update. The replacement part that Catalina Direct sells is the Catalina part, FYI.

When I removed my aluminum spreader brackets I did find some hairline cracks. They may have been there since casting or introduced later, who knows. I also see the same cast aluminum bracket on another mast I have spare from a different boat builder who obviously used the same spar manufacturer. The mast extrusion is identical to that on my C27 and the spreader bracket of identical design is definitely broken. The issue is not Catalina-specific due to the nature of the boat building business. The spar manufacturer no doubt sells or sold to several different builders, and parts like spreader brackets are not boat-specific.

It is easy to look at the force vectors and assume that the bracket is always in simple compression, but as I look at my old spreaders, (soon to be replaced) there is evidence that they also had side-loading, i.e more of a bending as evidenced by the wear right at the old spreader bracket, no doubt from using shrouds as hand holds.

If you have the stick down for maintenance, this would be an obvious thing to consider as part of your maintenance. Just be aware that there is likely to be a lot of white powder corrosion from the galvanic action between the stainless bolts and the aluminum. My old parts were kinda tough to get off, but just be patient and know they will come apart no matter how "welded" together they appear. Be sure to use the Tef-Gel when re-assembling to prevent this in the future.

Nom-
I followed your posts quite clearly and easily... FYI
 

mortyd

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Dec 11, 2004
952
Catalina 30 easy living
look, i certainly don't want to make this a spitting contest but i'm and aeronautical engineer with years of flight test experience and know something about structures and metals. when you guys use terms like force vectors and moment arm where are they coming from? i own a catalina 30 so really don't know how much of a problem soreader failure on catalina 27's but when i see advice coming from left field spoken in stenorian terms it bothers me because people are looking for informed anwers and i do not consider reccomending a part a middleman buys from catalina yachts and marks up that. i'm not particularly cranky this rainy morning but do try to help people on this forum and try keep quiet when i can't.

again, my advice is to buy the original part from catalina yachts.
 
Dec 11, 2008
1,338
catalina C27 stillwater
Morty-
My communication comes from a degreed Mechanical Design Engineer. I ended up in the audio profession as a designer but I almost became a doctor and prosthetics engineer, my first offer out of school. I might have stayed at a Holiday Express last night also, but that is not relevant to the question above. I have engineered concert sound for Garth Brooks, Herman's Hermits, Gary Pucket, Brandford Marsalis, Bobby Rush, The All American Rejects, The Jacob Fred Jazz Odyssey, to name a few but that is not relevant either is it? Kind of like your comment about being afraid of commercial airplanes? Now you know my professional credentials...


As a semi-professional boat restorer, (side job / hobby ) and the owner of a Catalina 27 I have seen the bracket in question in at least two different instances as being compromised. I feel I am qualified to respond to his query as to who has replaced the aluminum casting. I recommmend Ajay replace the cast aluminum one with the stainless replacement. Where he gets it is his call; it is the same part either way.

By your admission of not knowing much about the Catalina 27 spreader bracket, I wonder if you only jumped in to give Nom a hard time? thats fine, it is good to jab with ya.
 

mortyd

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Dec 11, 2004
952
Catalina 30 easy living
that my friend is a perfecltly valid and cogent anwer, and i 'jumped in.' as is my wont whenever anybody talks about speding extra money for unkown parts from catalina direct as opposed to from catalina yachts; no more, no less. ok? and as an engineer i'm sure you agree to use the terms 'aluminum' or 'stainless steel' is just about meaningless since there are so many alloys, tempers and finishes.
 
May 6, 2012
303
Hunter 28.5 Jordan, ON
look, i certainly don't want to make this a spitting contest

...clearly you do...

but i'm and aeronautical engineer with years of flight test experience and know something about structures and metals.

This is irrelevant if you aren't considering the specific application. This specific application (and the spreader brackets on the C22 for that matter) is known to be problematic.

when you guys use terms like force vectors and moment arm where are they coming from?

The dictionary rather than some abstract or esoteric use.


i own a catalina 30 so really don't know how much of a problem soreader failure on catalina 27's

...this makes your commentary all the more astounding...


but when i see advice coming from left field spoken in stenorian terms

...you are projecting here...


it bothers me because people are looking for informed anwers and i do not consider reccomending a part a middleman buys from catalina yachts and marks up that.

This last thought is incomplete or poorly worded at best, or based on an unrelated agenda at worst. I said make the upgrade. I didn't say where to buy the upgraded part from.


i'm not particularly cranky this rainy morning but do try to help people on this forum and try keep quiet when i can't.

This is great - stick to the plan.


again, my advice is to buy the original part from catalina yachts.

The original part is under-engineered and has been proven ineffective. Buy the upgraded part from wherever you like (CY or CD are two sources that have been mentioned).
I generally prefer to avoid debating with somebody who appears to have an axe to grind, as it usually degenerates into a thread-hijack. I believe my opinion was stated as was requested. I'd be happy to continue this tangential debate offline in PM.

Use the Google machine if you'd like to gain a better understanding of how widespread (ha) the problem is. I don't intend to line up my credentials in every post other than in this particular instance to say that I've owned and replaced this spreader-bracket type on a C22, have an understanding of the physics, problem and materials, and have read and discussed reports of the problem elsewhere.

philwsailz - appreciate the validation.
 
Dec 11, 2008
1,338
catalina C27 stillwater
that my friend is a perfecltly valid and cogent anwer, and i 'jumped in.' as is my wont whenever anybody talks about speding extra money for unkown parts from catalina direct as opposed to from catalina yachts; no more, no less. ok? and as an engineer i'm sure you agree to use the terms 'aluminum' or 'stainless steel' is just about meaningless since there are so many alloys, tempers and finishes.
Your comment regards to metals is true EXCEPT in instances like those in this thread. The reason is that the makeup and treatment of the aluminum part and the stainless part in question are pre-defined. The aluminum part is the stock part of old and the stainless part is the stock part of new. To know if the stainless part is 304, 316, 316L, whether it is passivated etc. is irrelevant for Ajay's sake as we are buying these instead of fabricating them.

We trust that the designer of the new part has done their work, and in this instance it will have been Gerry or Frank as I know for fact that the part is the same regardless where it is purchased....

We at least agree that Ajay should make the replacement move if he has the stick down, right? :D
 
Dec 11, 2008
1,338
catalina C27 stillwater
Sorry Ajay, we are bickering, (bench racing?) and its not your issue! :D

I say do the uprade to the stainless part. I don't care where you buy it, but know the replacement is the same from both of the two sources mentioned....

Any questions on how do to it, give me a shout. There is a trick to pushing the compression tubes up into the mast...
 

mortyd

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Dec 11, 2004
952
Catalina 30 easy living
phil, we could not agree more and that is why i am a catalina fan. but who knows what kind of pot metal people other than frank and gerry are using? surely you know what junk metal has invaded us. just read 'practical sailor.' and lots of sailors stil think catalina direct is catalina yachts.
 

mortyd

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Dec 11, 2004
952
Catalina 30 easy living
and, yes, i can't imagine taking the mast down and putting it back up with a spreader you don't trust.
 

mortyd

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Dec 11, 2004
952
Catalina 30 easy living
and, phil, for those who haven't followed practical sailor's recent stories about 'stainless steel,' the kind of 'stainless steel' in the real sailing world is very much relevant.
 

Faris

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Apr 20, 2011
232
Catalina 27 San Juan Islands
When people start stating credentials, you know the thread is heading nowhere good, though this one seems to have recovered. I just want to point out, parenthetically, that in an anonymous forum, saying "I prefer X", is not substantively different than saying, "As a Nobel Prize winning engineer with 100 years of experience working with X and Y, I prefer X." The credentials clause is just about ego or trying to establish credibility. The problem with credibility is that, the reader needs to believe you in the first place or the credentials argument is voided. That just leaves ego, and I say this as a person with a PhD in psychology and having spent the last 100 years studying this phenomenon ... and I invented the internet.

My response to Ajay's original post:

Most people (obviously at this point) agree that replacing the bracket is a good idea. The practical part of this advice is that, at least anecdotally, the SS bracket is less prone to failure, or at least failure without warning. I don't personally have any experience with anyone who has had this happen, so I don't know how much of this risk is theoretical and how much is statistical. (I recently had a bunch of people swearing that I would spontaneously lose my keel if I didn't sister the old keel bolts, though no one could produce an example of this having ever happened.)

But, I do know this:
Sailors do a lot of worrying about theoretical risks. That is, they tend to err on the side of caution and devote quite a bit of time and money addressing things that are, in actuality, only theoretically a risk, even when there is no evidence that the problem has ever occurred. There are good reasons for that caution, but it must be tempered with reason.

Now, spreaders and spreader brackets DO fail, and the risk of demasting at that point is not simply theoretical. Do THESE brackets fail? Well, according to a few sources (those who sell the upgrades), they do. I would ask the forum at this point, "Who here has any knowledge, direct or otherwise, of anyone who has had this happen?"

I honestly don't know. It could be that it happens all the time. I've just never heard of it ACTUALLY happening.

With that said, to me, it's not worth the risk. The new brackets are, what, $100 - $150? I personally wouldn't bring the mast down just to make this change, but if the mast was down for any reason, I would replace them. This is just a peace-of-mind issue for me, having some knowledge of how aluminum fails vs steel.

And with that said, as has been mentioned, you can't really say much summarily about either aluminum or SS. There is so much variation, in particular because many materials are called "aluminum" which are actually alloys. I don't know enough about either material, or the actual quantified forces involved at the spreader bracket, to make an informed decision about which grades of either aluminum or SS are suitable.

Unfortunately, neither does anyone here, despite stated credentials to the contrary. In terms of engineering, the problem is VERY complex and cannot be summed up with knowledge of the specs of the relevant materials.

A good friend of mine is a pipe engineer (yes, there really is such a thing). We were discussing bike frames (actually the relative merits of aluminum vs steel). He explained to me that the problem was so complex that you could do a dissertation on just one joint in the bike, and still get it wrong when it comes to what actually happens. Early aluminum bike frames DID crack and fail without warning. This is not because the engineers were inept, but because they lacked empirical data about what would actually happen in the real world. Aluminum frames have been around a while now, and they no longer have this problem, demonstrating that it is not the material, it is the knowledge of applying the material appropriately, informed by the actual stresses involved and the material's responses to those stresses.

This brings me back to my earlier point that, before saying that the "upgrade" is better, I'd like to know empirically that the aluminum one fails more frequently (under comparable conditions) than the SS one. I don't think anyone can make the claim to have reliable data for this. So, it just leaves us with the peace-of-mind factor.

But, I will say this. The cast aluminum bracket was likely produced merely with economy in mind. The SS bracket is produced, at least apparently, with materials that have been proven in similar applications. I don't think that we even actually know what materials the aluminum brackets were produced with. (Does anyone here know this?)

So, all I think that we can say that the SS brackets are probably reliable, and that there is less of a chance that the aluminum brackets are as reliable. But, I don't think we can say (at least not with the information I am aware of) that either is inadequate.
 

Faris

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Apr 20, 2011
232
Catalina 27 San Juan Islands
And, ditto on what Phil said about installation being tricky. I haven't done it, but my buddy just did, and he had a bit of a time with it.
 
Feb 26, 2004
22,760
Catalina 34 224 Maple Bay, BC, Canada
Faris's #18 post is well presented. One thing to add: regardless of how old something is, and usually because it IS old, improvements have been made because of incoming reports that mention failures. It's like building a better mousetrap. Hope ya don't have mice. :)
 
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