BC23 gooseneck

[MarkDarley]

Is anyone else concerned that the gooseneck is undersized for the power of the mainsail?
I keep bending the pins, and now also the gate for the pin.
See photo below.

[MarkDarley]

If you click on the photo it will turn the right way up!

[Llafurio]

Mark,
I am not concerned that the gooseneck fitting is per se undersized, but I think it is ill used in your case.
What bothers me is how the the two flanges which should be parallel are now opened wider. -Which puts more lever on the pin. The pin itself is far too long, for sure. It should be long enough to span the two parallel flanges, and no longer.

That the lower flange is at a different angle from the upper flange, indicates that ther must have been too much downward pressure (pull) on the gooseneck. I wonder why that is. Maybe that was caused by reefing lines led back to the mast and then down to deck. If that is so by design of the reefing system, then indeed the gooseneck fitting is not adequate for it.
C.

[MarkDarley]

Llafurio,
The gooseneck and pin are as supplied by the yard.  I would have fitted a shorter thicker pin but the flanges are light (too light) and will not accept the next size up.

I don’t think the reefing lines are the problem as all the tension is up not down as they are cleated on the boom.
My guess is that it is the boom vang/ kicker pressure. With a big roach in the main, the vang has to take a lot of pressure down and forwards because, dinghy style,  it leads to the base of the mast, not onto a track on the deck.

[Llafurio]

...
My guess is that it is the boom vang/ kicker pressure. ...

Ah, that explains it. The Allen gooseneck is fine as a hinge, but not for holding major forces down or up at the same time.

Good luck,
C.

[MarkDarley]

David Downs responded to me that he uses a simple nut and bolt instead of the pin. Perhaps compressing the flanges will strengthen the whole thing.

[Llafurio]

Yes, that would strengthen it against bending by at least 100 %. Because then the downward pull would be born by both the upper and the lower flange together, and the bending lever on the pin/bolt would be reduced also. Good solution.
C.

[Sea Simon]

I think the same Allen boom fitting is on BRe?
The fitting is/was quite cheap (appx £35?) But removing old (bonded/bedded) and fitting new to the mast is a bit of work, and you need correct "carbon friendly" pop rivets. At least it's pressed S steel, not welded!

I did not have Mark's problem, but rather found it difficult to insert the boom vertical hinge pin when putting the mast up single-handedly, especially afloat (perhaps a peculiarity of my local circumstances?) The sail having remained attached and rigged to the wood boom. I then noticed that the boom to gooseneck connection is a substantial pressed steel pin (the bit stamped Allen, to the right) and socket arrangement,  with a nice big taper, making it much easier to align - to "plug in". This is in turn secured thru the boom, by a large horizontal drop nose pin, like Mark's bent one.
The BC 23 may perhaps be similar?

Bear with me...

This allowed me to change the goose neck Swivel pin (the vertical drop nose pin in OP) for a properly fitted BOLT.
Not a machine screw (the fully threaded item). Perhaps rather nerdy, but the difference  sometimes matters, as in this case, imho. I've  posted on here before about this.

The ability  to derig easily retained by unplugging the gooseneck pin from the boom, and the gooseneck hinge pin can remain in place. Fiddly to remove/fit a bolt (especially  with washers) in this location .

I also inserted nylon washers inside the mast fitting jaws, so as to make it all a bit "kinder" on itself, afap.
Once nipped up, and suitably locked off, the misaligned forces are eliminated and load paths should be closer to design intent.

Try and source such critical bolts/pins from a reputable source (eg Allen, Seasure or similar) not anonymous  suppliers on EBay.

Q. Is the BC 23 kicker attached to the mast heel via a pressed S steel riveted on tang? Probably Allen too?
If of any concern to you (for example venturing offshore)...several racing dinghy classes habitually back up such attachments with Dyneema lashings. That will at least get you home.
I did similar on my vang and sheet attachments to the BRex booms, not being very comfortable with the original wood screws, dominantly in tension/pull-out orientation.

PS. The proposed mod would also get rid of that rather angry looking (and damaged) nose on your pin. God forbid that contacts your mast! Good luck with extracting that bent pin.