gooseneck failure

[Ken Heyman]

During a Labor Day Sail today in near perfect conditions, albeit a lumpy Lake Michigan with Northeast winds, my wife and I were startled by a metallic "bang'. It turned out that the gooseneck had failed allowing the boom to crash to the deck and become quite "untamed" . I secured it to the lifelines and then lowered the main and continued sailing with the genoa. When we arrived at our mooring and I inspected the rig, I saw that the pin that normally resides inside the boom and allows the boom to rotate had exited the boom and  was now on display and securely attached to its fitting on the mast. I took the cap off the front of the boom and inspected the inners. As suspected, the cotter pin that is inserted into the end of the pin had completely disintegrated. In the 10 years that I've owned the boat, I only had the front boom cap off once before when I repaired the outhaul. Needless to say this is worth inspecting. While the boat was never in jeopardy, certainly crew could be injured if they happened to be under the boom when it let go. I was curious if this had happened to others and sure enough------


http://c34.org/bbs/index.php/topic,209.0.html

Ken

[Gary Brockman]

Ken -

The same thing happened to me during a daysail about 3 years ago but the solid vang kept the boom off of the deck.  I installed a new cotter pin and forgot about it until 2 weeks ago when it happened again on the first windward leg of a 14 mile random leg race.  I was lucky to have Aleks (a rigger) crewing for me that day and he was able to jury rig a workable solution using short pieces of dyneema line within 5 minutes of it happening and we were still able to take 2nd in the race. 

After the race we looked at the problem and Aleks suggested that instead of inserting a new cotter pin as a short term solution that he take it to a welder and have the pin welded into the end fitting by welding the washers to the pin so that the boom is still free to turn on the pin but won't have a surprise separation. This made sense to me so we did it.  Its only been 2 weeks but it held up this weekend in a 30 mile race in 20-25 kts.

Gary

[Ken Heyman]

Thanks Gary,

As an aside, I also have a Garhauer rigid vang. Nonetheless, it didnt suport the boom vertically as it rotated allowing the boom to collapse on the deck, once the gooseneck failed.---hmmmm? It remains attached at the boom and mast attachment points but was still able to rotate and not suport the boom---don't quite understand why ? 
Ken

[Ed Shankle]

Go back a couple of months on the message board and you'll see I ran into the same thing. Seems like a real weak point to me. Had a devil of a time getting the end cap off, but eventually did, with a cold chisel! At the time I just wanted to get it quickly repaired, as my about to leave for 2 yrs in the Peace Corp daughter wanted to get in some sailing time with me. but I do intend to get back in there to apply a more secure fitting. Thought I'd drill out the hole a bit more, to accept a true pin instead of a cotter pin.
My Garhauer rigid vang did hold up the boom despite the separation, which was good to confirm. Although I did wonder if something subtle that I did wrong in the installation of the rigid vang contributed to the failure. Or mabe it was just it's time; as I said seems like a weakness in the design.

Ed

[Ron Hill]

Guys : In one of my "Tips" from long ago, I mentioned how to insert cotter pins and regular pins.

The loop of the cotter pin and the head of a regular pin should always be UP.  So gravity will always hold it in place. 
"Aircraft Maintenance 101"

[mainesail]

We had this same failure on a C-36. It is a pretty cheesy way to hold a gooseneck on. On ours the pin literally sheered leaving the pin hole full of pin and the other ends of it inside the boom. I over drilled the pin hole to use a larger pin and also made a new washer with a tighter tolerance.

Not really the most robust gooseneck design.....

Here you can see the sheered cotter pin still in the hole....


To get back to port I re-inserted the gooseneck into the boom then made a boom "inhaul" using the green line pictured and a truckers hitch. I took two reefs, rigged a preventer and we made it without issue despite it gusting to 25 knots..



Once in port getting the end cap out of the boom proved pretty tough as the factory did not use an anti-corrosives like Lanolin or Tef-Gel on the screws. Once the end cap was out the fix was easy. The hole was pretty close to the end of the pin but had enough meat to go to the next size up pin. I found the washer WAAAAAY to sloppy and this is likely why it sheered the pin as there was too much slop.


But one of the small details that make these boats great coastal cruisers but not the best suited for ocean crossings.... I mean really, how much did they actually save on this cost cutting design flaw......

[Ken Heyman]

Guys,
It took me about 15 minutes to coerce the end cap off with screwdriver and rubber mallet
I called Garhauer and they confirmed that they wouldn't expect the rigid vang to support the boom once the boom is free of its mast attachment point and rotates horizontal.
Ken

[Dave Spencer]

Despite knowing what to expect when I removed the end cap from my boom to upgrade the outhaul and inspect the notorious gooseneck cotter pin, I was somewhat shocked to see how fragile the assembly was.  My pin was bent but not broken although the head of the cotter pins showed definite wear as seen in the detailed picture below.  I took mainesail's advice and drilled out the cotter pin hole 1/64" at a time to get to 13/64" so I could replace the old pin with a stronger 3/16" cotter pin.  I also checked the Catalina Direct website to see what a new endcap would cost.  Not too bad at $89.  What caught my eye on the CD website was the following note on the endcap page -

"Note: With the advent of rigid boom vangs, Catalina changed the design of the gooseneck. In order to reduce the load on the vang end fittings, the boom no longer rotates. The stainless stud is now fixed in the casting."
http://www.catalinadirect.com/index.cfm?fuseaction=product.display&product_ID=957&ParentCat=634

I know many had trouble removing the endcaps but I had very little difficulty.  I had a can of PB Blaster standing by but the screws came out easily and the endcap came off quickly with some gentle persuasion with a plastic mallet. It's easy to see how this could be more difficult on salt water boats.

[Mark Sutherland]

Here's a photo(hopefully it's attached, link to Cat Direct: http://www.catalinadirect.com/index.cfm?fuseaction=product.display&Product_ID=957) of the upgraded gooseneck I just installed.  You can see that there is a large SS pin holding the gooseneck stem in place which also eliminates "roll", or "twist" in the boom and eliminates torsional stress on your rigid vang.  I used a "slide hammer" to remove the casting/cap from the boom.  The outhaul assembly and associated line was in pretty bad shape, which I anticipated, so I replaced it with a 10:1 model I bought from catalina direct(the outhaul I bought was designed for the 30 but fit just fine.  I had them add an extra 20' of line, just in case of any length issues....).  I sanded and cleaned the inside of the boom and coated the casting with Lanocote prior to installation.  New outhaul works like a dream.  Unbelievable how little effort it takes to haul out the clew.

[Switchback]

Hi Mark, how did you secure the new casting to the boom? It does not seem to have the holes where the rivets should go through.

Here's a photo(hopefully it's attached, link to Cat Direct: http://www.catalinadirect.com/index.cfm?fuseaction=product.display&Product_ID=957) of the upgraded gooseneck I just installed.  You can see that there is a large SS pin holding the gooseneck stem in place which also eliminates "roll", or "twist" in the boom and eliminates torsional stress on your rigid vang.  I used a "slide hammer" to remove the casting/cap from the boom.  The outhaul assembly and associated line was in pretty bad shape, which I anticipated, so I replaced it with a 10:1 model I bought from catalina direct(the outhaul I bought was designed for the 30 but fit just fine.  I had them add an extra 20' of line, just in case of any length issues....).  I sanded and cleaned the inside of the boom and coated the casting with Lanocote prior to installation.  New outhaul works like a dream.  Unbelievable how little effort it takes to haul out the clew.

[mark_53]

Hi Mark, how did you secure the new casting to the boom? It does not seem to have the holes where the rivets should go through.

The holes are not pre-drilled in the casting because they might not line up with where your boom holes are located.  Drill and tap the fitting to match your boom holes.  Use four SS screws with anti seize. 

[Switchback]

Hi Mark, how did you secure the new casting to the boom? It does not seem to have the holes where the rivets should go through.

The holes are not pre-drilled in the casting because they might not line up with where your boom holes are located.  Drill and tap the fitting to match your boom holes.  Use four SS screws with anti seize.

Thanks Mark,

I went out and bought all the necessary tools/hardware. Will be attempting this project very soon!

[csimmerling]

it's not clear to me from that description on the CD site (about non-rotating for rigid vangs) if this new casting is also appropriate for people who haven't upgraded to a rigid vang. I want to avoid the cotter pin shearing problem, so am I better off with the new casting, or trying to enlarge the cotter pin hole?
thanks

[Phil Spicer]

You could cross drill the casting and ss pin all at one time and drive a ss rod through the whole gooseneck. Use a 3/16" drill and ss rod. Big savings!

[Switchback]

UPDATE

I was able to finally get this project completed yesterday! Woohoo! I drilled out the rivets with a 1/4" drill bit and used a screw driver to push them out of the hole and into the inside of the boom. I then held a screwdriver against the end cap and banged the other end of the screwdriver with a rubber mallet to work the cap off. Don't forget to loosen the outhaul! This took a few minutes as there was a small bit of corrosion on the inside of the boom. I sanded this off and then applied a healthy layer of lanocote to the inside of the boom where the end cap sits. Then i removed the rigging from the end cap and spent quite a while trying to get the pin out that holds in the sheave. This was held on tight by lots of corrosion. I let it soak in a ton of WD40 then used a hammer to bang it out. Next I coated the new upgraded end cap with lanocote, slapped on the rigging (with a brand new sheave and pin) and used the rubber mallet to get the cap on the end of the boom. Then I pre-drilled the first screw hole which I ended up doing too small and it resulted in shearing the head off the machine screw. OOPS. removing this will be a project for later... I was able to get the rest of the 3 screws (which I also coated in lanocote) in without a problem by switching to a larger drill bit, just down 1 size from 1/4". I drilled the self tapping screw in slowly and backed them out a bit then screwed in further and repeated this until the screw was all the way through. I used pretty short 1/4" stainless steel screws and added nice wide washers as well. On one of the screw holes on the boom there was a pre-existing hairline crack. I figured the washer would help spread out the force a bit better. My surveyor said the crack should not be an issue in any case... This project took the afternoon and honestly there was only mild frustration. Very happy to have the boom operational once again! Thanks to everyone for the tips and assistance. It was incredibly helpful!

Parallel thread: boom gooseneck  http://c34.org/bbs/index.php/topic,10037.0.html