Is this block the one to use?

Richandhelen

Richandhelen

.
Feb 3, 2014
94
Hunter 44 aft cockpit Miami, FL
It was stormy, windy and tricky on Biscayne Bay today. With winds gusting to 20 knots I decided to add a reefed main to the already reefed Genoa. Turn to windward, ease the outhaul, furl some main and tighten the outhaul. BANG! What was THAT? A quick survey showed that the block at the base of the mast which directs the outhaul back toward the cockpit had broken.

image-348639571.jpg

Note that both the shackle and the block itself are broken. My boat is a 2006 and the blocks are original. Do I need to change them all? Any quality issues with this Lewmar? Suggested replacements?

Thanks!
 
Kings Gambit

Kings Gambit

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Jul 27, 2011
5,134
Bavaria 38E Alamitos Bay
Richandhelen said:
It was stormy, windy and tricky on Biscayne Bay today. With winds gusting to 20 knots I decided to add a reefed main to the already reefed Genoa. Turn to windward, ease the outhaul, furl some main and tighten the outhaul. BANG! What was THAT? A quick survey showed that the block at the base of the mast which directs the outhaul back toward the cockpit had broken.

View attachment 91602

Note that both the shackle and the block itself are broken. My boat is a 2006 and the blocks are original. Do I need to change them all? Any quality issues with this Lewmar? Suggested replacements?

Thanks!
Click to expand
I've had something like that happen twice. First, the shackle holding my mainsheet block assembly to the boom of my Pearson 30 "exploded" when I gybed (controlled) in high wind (20 kt); the second on my present boat, the Bavaria, was when an SS ring of a batten car holding a luff attachment of my mainsail exploded. In the first case, the shackle was more 15 yr old; in the second the ring only 6 or 7 yr old. I replaced only the broken items rather than the entire respective assemblies. Apparently, some SS hardware are not perfectly made in every lot. Failure in one might not portend other failures in the near future.
 
kloudie1

kloudie1

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Nov 6, 2006
10,115
Hunter 34 Mandeville Louisiana
Probably a shackle only failure.. The plastic is not load bearing and probably cracked from the impact after the shackle failed. You could replace the shackle only.. Do inspect the other block's shackles .. that looks like a substandard piece because of the large amount of rust on the "stainless".. Ya might want to take some good pictures and talk to the Lewmar folks.. they may want to replace it for you, since that is not a normal failure.
 
Richandhelen

Richandhelen

.
Feb 3, 2014
94
Hunter 44 aft cockpit Miami, FL
kloudie1 said:
Probably a shackle only failure.. The plastic is not load bearing and probably cracked from the impact after the shackle failed. You could replace the shackle only.. Do inspect the other block's shackles .. that looks like a substandard piece because of the large amount of rust on the "stainless".. Ya might want to take some good pictures and talk to the Lewmar folks.. they may want to replace it for you, since that is not a normal failure.
Click to expand
Great idea. Worth a try. Rich
 
Sailgunner

Sailgunner

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Jun 4, 2004
1,087
Mainship Piliot 34 Punta Gorda
The shackle breaking is kind of surprising. I had to replace all my blocks at the base of my mast when the boat was 12 years old. The sheaves all deteriorated from the Florida sun. Mine were all Sheafer but I see yours are Lewmar so they wil probably last longer.
 
Stu Jackson

Stu Jackson

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Feb 26, 2004
23,087
Catalina 34 224 Maple Bay, BC, Canada
Glad to hear that worked.

I bought two Lewmar blocks for my cunningham. BOTH of them literally dissolved after only a year.

All the rest of my blocks are Garhauer, some of them nearing 30 years old and flawless.

Guess what I'd suggest. :)
 
D

Dan_Y

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Oct 13, 2008
519
Hunter 36 Hampton
Did Lewmar happen to say if they actually made the shackle? Just curious.
 
kloudie1

kloudie1

.
Nov 6, 2006
10,115
Hunter 34 Mandeville Louisiana
Good news, Rich..
Lewmar would have bought the shackle from a supplier.. That one looks like it is not the correct stainless recipe .. probably from an "offshore" supplier.
Glad that Lewmar stepped up and corrected it for you. I think they took a step to "the dark side" a few years ago and are now getting back to better quality control..
 
Richandhelen

Richandhelen

.
Feb 3, 2014
94
Hunter 44 aft cockpit Miami, FL
kloudie1 said:
Good news, Rich..
Lewmar would have bought the shackle from a supplier.. That one looks like it is not the correct stainless recipe .. probably from an "offshore" supplier.
Glad that Lewmar stepped up and corrected it for you. I think they took a step to "the dark side" a few years ago and are now getting back to better quality control..
Click to expand
I'm sorry, but I didn't think to ask if they actually made the block since it bore their name.

The real problem with this sort of metal failure, to me, is the looming prospect of another bad piece of metal. And a failure which, by Murphy's law, will occur at the worst possible moment.

Like all of you, I have numerous additional blocks with shackles. So do I preemptively replace them all since they are the same age? If I replaced all of the stainless bits on the entire boat that have a bit of discoloration....... Well, you know. That is not practical, affordable or even indicated. ALL of the aft-led blocks from the base of the mast back to the cockpit are under some greater-or-lesser load (halyards, main furl, outhaul, main sheet).
 
kloudie1

kloudie1

.
Nov 6, 2006
10,115
Hunter 34 Mandeville Louisiana
Rich, if you look carefully at your other shackles and compare them to that one, you should be able to tell quickly, by inspection, which ones are wonky. They should not have the deep rusty pits in them that you can see around the cracked edges of the bad shackle. A little bit of surface rusty color over shiny stainless is kind of OK.. pits with rust bleeding is definitely not.. If you have an engineer buddy who does corrosion analysis, bribe him with beverages of his choice to have a look-see..

EDIT: Don't NEVER EVER (as my buddies in Mississippi would say) use a bleach cleaning mixture around stainless that can be highly stressed.. it can accelerate corrosion in stainless
 
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Richandhelen

Richandhelen

.
Feb 3, 2014
94
Hunter 44 aft cockpit Miami, FL
kloudie1 said:
Rich, if you look carefully at your other shackles and compare them to that one, you should be able to tell quickly, by inspection, which ones are wonky. They should not have the deep rusty pits in them that you can see around the cracked edges of the bad shackle. A little bit of surface rusty color over shiny stainless is kind of OK.. pits with rust bleeding is definitely not.. If you have an engineer buddy who does corrosion analysis, bribe him with beverages of his choice to have a look-see..

EDIT: Don't NEVER EVER (as my buddies in Mississippi would say) use a bleach cleaning mixture around stainless that can be highly stressed.. it can accelerate corrosion in stainless
Click to expand
I used a jeweler's loupe to have a look at the metal. The SURFACE looks fine - just discolored. If I used a polish on it, I think it would look brand new. But the metal INSIDE is absolutely "spongey" looking - not pure metal - absolutely porous.
 

Attachments

kloudie1

kloudie1

.
Nov 6, 2006
10,115
Hunter 34 Mandeville Louisiana
Yup.. really a bad piece of metal.. (nice picture) You probably would have seen a crack that made the rusty stain, had you looked at it before it broke.. Good inspection job ! .. notice how the stain is speckled in many places .. the furthest away shackle leg, about half way along it .. you can see speckles.. different from the way rust stains look from not being passivated correctly..
Stress corrosion cracking is probably what did the break..
http://www.corrosion-doctors.org/Forms-SCC/scc.htm
 
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