Gooseneck wear

[PabloPicasso]

Is this gooseneck wear normal? Surely the metal bearing surfaces should be hard enough to resist this kind of wear?

 

[Max Campbell]

How old, how much use?

 

[PabloPicasso]

New spars 8 years ago-ish. Round the cans club racing once a week during the season. Winters ashore mainly. Some years we cruised gently for a week with family aboard.

 

[TernVI]

I suspect 90% of it happens when the boom is swinging a little while the sails are stowed?

There is sometimes a washer or two as a bearing surface.

 

[Daverw]

I would have expected to see two washers as bearing surface rather than aluminium on aluminium

 

[LittleSister]

I suggest this for goose neckwear:

 

[penfold]

I would have expected to see two washers as bearing surface rather than aluminium on aluminium

It certainly would have benefited from something like that! Given the degree of wear washers may not help, short of a completely new fitting I'd overbore and fit tophats(could be stainless, but I'd prefer acetal or maybe nylon), probably epoxied in place. It's also worth looking at inverting some or all of the fitting if that is possible to use unworn bearing faces.

 

[PabloPicasso]

Using top hats is an interesting idea
I think I'll try and replace the complete fitting (an in-service failure might'nt be good for the blood pressure) . Perhaps adding some sacrificial washers. Perhaps there were some when new?

To remove it I can drill out the 8 rivet heads and remove the two S/S nuts. Will the 2 S/S bolts stay put or fall down inside the mast? Anyone familiar with Z spars able to answer that?

 

[mikegunn]

I suspect 90% of it happens when the boom is swinging a little while the sails are stowed?

There is sometimes a washer or two as a bearing surface.

That’s what I’ve found too. On the basis that prevention is better than cure I always rig strops from the boom end to deck fittings, port and starboard. The effective triangulation of the strops when combined with the topping lift virtually eliminates any movement of the boom.
Mike

 

[penfold]

To remove it I can drill out the 8 rivet heads and remove the two S/S nuts. Will the 2 S/S bolts stay put or fall down inside the mast? Anyone familiar with Z spars able to answer that?

I imagine they will be T-bolts of some kind so will probably slide freely up and down the groove; worth wedging something in the gap to stop them falling all the way down, a loose roll of masking or gaffer tape works well and easy to adjust the size of.

 

[pyrojames]

Looks like wear when moored. There shouldn't be any load at that surface with the halyard tight.

Edit: auto correct put in "intrigued" when I meant moored or stowed or something!

 

[TiggerToo]

TT's boom-to-gooseneck contact suffered from the same problem in the first years of her life. At some early point (as a coding/rigging (?) result of a surveyor pint this out to us) I put on a couple of nylon washers. These are sort of sacrificial, as they wear out in a year or two, but thy are cheaper than (a portion of) chips and not too difficult to change. Pennies well spent!

TT's boom-to-gooseneck is now 23 years old and looks much less worn than that (i.e. the wear on the aluminium has stopped).

 

[Spirit (of Glenans)]

That’s what I’ve found too. On the basis that prevention is better than cure I always rig strops from the boom end to deck fittings, port and starboard. The effective triangulation of the strops when combined with the topping lift virtually eliminates any movement of the boom.
Mike

My solution is to drop the boom down on to one of the cockpit seats when the boat is moored.

 

[jwilson]

I suspect 90% of it happens when the boom is swinging a little while the sails are stowed?
There is sometimes a washer or two as a bearing surface.

I agree - much of the wear is when moored and unused, even slight swinging eventually wears away the alloy. I tie my boom off firmly to one side when moored for any length of time. The bigger and heavier the boom the more this happens: never had to do it with smaller boats.

 

[PabloPicasso]

Would it be good to use collidial silica to thicken epoxy with this repair?

 

[Daverw]

I would look at taking off and getting a local machine shop to either weld up and machine or mill and machine a suitable insert, then refit with spacer washers