Main sheet tackle broken catch


Matti Lohikoski
 

Dear Amelians,
when Olivier did the survey of Borador he noticed the "Main sheet tackle broken catch" was broken.
It seems to be a very difficult part to get and Amel does not have it.
Can anyone help with the size of the boom groove or the catch dimensions.
I would love to have it machined here in Finland rather than doing it with a disc grinder at site.




Matti Lohikoski SM#398


 

Matti,

Here is a page from my Amel Book which shows where you can get one and an alternative one piece which will probably never break.

Oh, and you can get the printed book here: https://preparetocastoff.blogspot.com/p/amel-book.html
CW Bill Rouse Amel Owners Yacht School
Address: 720 Winnie, Galveston Island, Texas 77550 
View My Training Calendar


On Fri, Mar 12, 2021 at 8:51 AM Matti Lohikoski <matti.lohikoski@...> wrote:
Dear Amelians,
when Olivier did the survey of Borador he noticed the "Main sheet tackle broken catch" was broken.
It seems to be a very difficult part to get and Amel does not have it.
Can anyone help with the size of the boom groove or the catch dimensions.
I would love to have it machined here in Finland rather than doing it with a disc grinder at site.




Matti Lohikoski SM#398


 

apologies, I meant to send the last email privately to Matti Lohikoski

Bill
CW Bill Rouse Amel Owners Yacht School
Address: 720 Winnie, Galveston Island, Texas 77550 
View My Training Calendar


On Fri, Mar 12, 2021 at 9:52 AM Bill Rouse <brouse@...> wrote:
Matti,

Here is a page from my Amel Book which shows where you can get one and an alternative one piece which will probably never break.

Oh, and you can get the printed book here: https://preparetocastoff.blogspot.com/p/amel-book.html
CW Bill Rouse Amel Owners Yacht School
Address: 720 Winnie, Galveston Island, Texas 77550 
View My Training Calendar


On Fri, Mar 12, 2021 at 8:51 AM Matti Lohikoski <matti.lohikoski@...> wrote:
Dear Amelians,
when Olivier did the survey of Borador he noticed the "Main sheet tackle broken catch" was broken.
It seems to be a very difficult part to get and Amel does not have it.
Can anyone help with the size of the boom groove or the catch dimensions.
I would love to have it machined here in Finland rather than doing it with a disc grinder at site.




Matti Lohikoski SM#398


Alan Leslie
 

Hi Matti,

We have had this issue in the past...the original is not a very good solution to a simple issue.
On the 54 they didn't use this system but had a plate welded to the underside of the boom.
When our last piece broke, our rigger made up a custom alloy plate and welded it into the slot underside of the boom.
He used a dyneema soft shackle to attach the block to this plate...much better!

Cheers
Alan
Elyse SM437 


Bill Kinney
 

Just a couple of general observations on the mainsheet to boom attachment on Super Maramus.  I do not think this part is underdesigned.  I think the issue is that boats are sometimes sailed in ways that the designer did not anticipate or allow for.  

We had Harmonie for over two years before I first heard about this issue on another SM.  I saw the damage, and pretty quickly afterwards heard of another boat with the same issue.  I realized I hadn't looked at this part closely on our boat, so put that on the checklist.  A detailed inspection showed that it looked exactly as it did when it left the factory.  This after 22 years sailing on two circumnavigations, and accumulating well over 100,000 sea miles. Based on what I saw, there was no reason to replace or change anything. So the idea that the design was faulty or fragile didn't seem to make sense.

It took me a week of thinking why this disparity might be before the light bulb lite up and the connection was made.  A rigger with a lot of Amel experience confirmed the answer:  Accidental gybes.  They can put a HUGE load on all the parts of the rig, especially the mainsheet attachment.  Everybody has them, (hopefully rarely!)  but with the way the SM is set up we can really reduce, or completely eliminate, damage done if we sail the boat "right".

The key to reducing the shock load on the boom is to ALWAYS, ALWAYS, ALWAYS move the traveler to the side of the boat where the boom is eased out.  That minimizes the length of the sheet, and hence the swing of the boom and the peak velocity of the boom during a gybe. NEVER sail the boat with the boom eased far out over the rail using only the sheet while keeping the traveler centered.  It is very inefficient in terms of sail shape, but much more importantly it is potentially risking damage to many parts of the rig if things go wrong.

I am convinced you can beef up this part all you want, but it you have a full flying gybe, stuff can still break.  I have seen booms snapped in half, and rigs taken down by accidental gybes. The forces can be darn close to irresistible, so everything that can be done to reduce those forces, should be done, and done every time we turn downwind.


Danny and Yvonne SIMMS
 

Hi Bill. With you on this. II would add use the preventer when running with eased sheets. I also agree with you about weak points. If the boom attachment fails it is an easy fix. Broken boom or rig?, Oh boy. So if the boom attachment fails and we beef it up perhaps we are advised to modify technique. 

Regards

Danny

SM 299

Ocean Pearl

On 13 March 2021 at 18:18 Bill Kinney <cruisingconsulting@...> wrote:

Just a couple of general observations on the mainsheet to boom attachment on Super Maramus.  I do not think this part is underdesigned.  I think the issue is that boats are sometimes sailed in ways that the designer did not anticipate or allow for.  

We had Harmonie for over two years before I first heard about this issue on another SM.  I saw the damage, and pretty quickly afterwards heard of another boat with the same issue.  I realized I hadn't looked at this part closely on our boat, so put that on the checklist.  A detailed inspection showed that it looked exactly as it did when it left the factory.  This after 22 years sailing on two circumnavigations, and accumulating well over 100,000 sea miles. Based on what I saw, there was no reason to replace or change anything. So the idea that the design was faulty or fragile didn't seem to make sense.

It took me a week of thinking why this disparity might be before the light bulb lite up and the connection was made.  A rigger with a lot of Amel experience confirmed the answer:  Accidental gybes.  They can put a HUGE load on all the parts of the rig, especially the mainsheet attachment.  Everybody has them, (hopefully rarely!)  but with the way the SM is set up we can really reduce, or completely eliminate, damage done if we sail the boat "right".

The key to reducing the shock load on the boom is to ALWAYS, ALWAYS, ALWAYS move the traveler to the side of the boat where the boom is eased out.  That minimizes the length of the sheet, and hence the swing of the boom and the peak velocity of the boom during a gybe. NEVER sail the boat with the boom eased far out over the rail using only the sheet while keeping the traveler centered.  It is very inefficient in terms of sail shape, but much more importantly it is potentially risking damage to many parts of the rig if things go wrong.

I am convinced you can beef up this part all you want, but it you have a full flying gybe, stuff can still break.  I have seen booms snapped in half, and rigs taken down by accidental gybes. The forces can be darn close to irresistible, so everything that can be done to reduce those forces, should be done, and done every time we turn downwind.


Alan Leslie
 

Absolutely correct Bill....but sometimes things happen.....
So, why did they change that block arrangement to the weldment on the 54?
Maybe because those blocks are a real pain to remove, if you ever have to.
I just think the weldment is a much better solution and those blocks disappeared forever when the SM was out of production.
Cheers
Alan
Elyse SM437


 

I am not sure if you are asking me, but my answer is always in those circumstances. 

Best,

CW Bill Rouse 
Amel Owners Yacht School
+1 832-380-4970 | brouse@...
720 Winnie, Galveston Island, Texas 77550 
www.AmelOwnersYachtSchool.com 
Yacht School Calendar: www.preparetocastoff.blogspot.com/p/calendar.html


   

On Sat, Mar 13, 2021, 3:54 PM Alan Leslie <s.v.elyse@...> wrote:
Absolutely correct Bill....but sometimes things happen.....
So, why did they change that block arrangement to the weldment on the 54?
Maybe because those blocks are a real pain to remove, if you ever have to.
I just think the weldment is a much better solution and those blocks disappeared forever when the SM was out of production.
Cheers
Alan
Elyse SM437