replacing clevis pin on a forestay

[asdf777]

Not sure if it's visible in the picture, but the forestay toggle is pushing down on the cotter pin so that it's bent a little and makes me nervous.

[IMG]http://www.sailblogs.com/sbgallery/pics/grybkin_gmail_com/sbdxfnqay/w/sb4hakks.jpg"]http://www.sailblogs.com/sbgallery/pics/grybkin_gmail_com/sbdxfnqay/w/sb4hakks.jpg[/IMG]

Would you switch the direction of the clevis pin or put in a shackle? The pin is 3/8". Does it make sense to put in a shackle of a smaller diameter? I have a Wichard 8mm HR shackle that should be stronger than a no-brand 3/8", but am afraid of a shock load of the pin hitting the chainplate in waves.

Thanks!
Gleb

[Douglas]

FWIW Gleb , of greater concern might be the surveyor's creed to never hang a structural fitting on a welded joint and what about the rusting corrosion under that Tee toggle ?

[asdf777]

Hi, Douglas,

Unfortunately, I don't have a picture of the bow from the anchor side - the chainplate connected to the forestay toggle goes down a foot or so and is bolted to the bow. The welding is not structural, but you're right - there is surface corrosion.

The boat is 35 years old and manufacturing and rebedding of the same bow plate would be a major and expensive undertaking... This bow plate does make me worry - it's the only original chainplate on the boat, even though the new ones have developed just as much corrosion in the last 2 years.

I was on a delivery trip last year on a Tayana 52, and the bow chainplate did fail at some point, so it's a scary thought. Luckily, we noticed it just in time, so the mast stayed in place:

http://www.sailblogs.com/sbgallery/p...w/sbnfu8mu.jpg

It would be great if there was a way to protect the forestay in case the bow chainplate fails, but I can't think of anything that could really help in my case.

Thanks,
Gleb

[Brion Toss]

Hello,
It is unlikely that reversing direction would help; a longer clevis pin is probably the most useful solution. It would be very hard to make a connection with a shackle that wasn't weak, in any event.
That staining worries me, too, because weld decay can easily result in corrosion of the actual stem fitting, as well as the flange that the weld is for.
Finally, what size wire is this for? What size boat?
Fair leads,
Brion Toss

[asdf777]

Thank you.

The boat is 1979 Bristol 29.9 = ~30' sloop. Forestay wire is 316 1/4" 1x19. This clevis pin should be 3/8". Last time the stem fitting and flange were professionally inspected was 2 years in the SF bay area. They had corrosion then, and there is more now.

Do you think there is something that can be done as a preventive measure?

Sorry, I didn't understand the part about the weak shackle connection. The forestay slid down either when mounting the mast or in waves - there is about 1/4" of free pin on the opposite side before the pinhead. I was thinking that the shackle body would hold the toggle in place even if the forestay toggle jaw moved up or down the pin. Basically, the shackle pin would be in the same place as the clevis pin now, and the D part of the shackle would hang in the air, like so:



This way I could also quickly attach a jib halyard and/or spinnaker halyard to the shackle in case the forestay breaks...

For example, Ronstan 3/8" wide or regular D shackle should have at least the same strength rating as the wire: http://www.amazon.com/Ronstan-Wide-D.../dp/B005O2QTVS

What do you think?

Many thanks!
Gleb

[Brion Toss]

Hi again,
Ah, I see now. Spacers would help to locate the toggle, to keep it from shifting. The shackle-outside configuration always struck me as a bit ... agricultural. On the other hand, you might have some cause to be concerned about a rig failure, as the correct pin size for 1/4" wire is 1/2", not 3/8."
Would you happen to know the tune on the backstay?
Fair leads,
Brion Toss

PS,
If you think redoing that antique stem fitting is expensive, just imagine what a dismasting would cost.