Nica and I are going to be working on bcc-mischief this summer - getting her back into sailing shape hopefully in time for Winter in the Bahamas 2023/2024. We have an ambitious list of projects, including inspecting the chainplates with the likelihood that we just replace them all. I believe she has the original 1983 SS 316 chainplates installed.
Todd (Cape George) uses bronze chainplates produced by PTF. That might be out of my league budget wise.
@Bil has several posts detailing his approach to replacing chainplates on BCC Zygote. Bil chose āduplexā 2507 stainless steel for its superior resistance to pitting and crevice corrosion - compared to say 316. Bil also had a shop laser cut the parts from cad files - which I think is interesting as well.
Bill has lots of posts on this topic - here are just a couple:
Iām contemplating working with a local SS fabricator - which would probably result in new SS 316 fittings modeled after the originals. Good for another 20 years I guessā¦
Or, working with Colligo Marine to get titanium chainplates fabricated. Has anyone gone down this titanium rabbit hole? Worked with Colligo on the project? How did cost estimates compare - titanium vs SS vs bronze?
@MCilenti, you had once upon a time mentioned that you were considering titanium chainplates. How did that go?
Can you provide some additional context around that $1754 figure? Is that Colligo titanium? PTF bronze? Or a local SS fabricatorās quote for SS316? Or something else?
@Adventure , a 1987 boat, reported a failed chainplate here:
The folklore I hear is that SS316 chainplates generally have a 20 year service life. But you can dye test them under a magnifying loup to determine when they are truly ādoneā. I have not done this with Mischief yet. I donāt think there are any absolute/reliable answers here other than understanding that the service life is finite.
Sorry, Its a quote I got This year from PTF for all 6 Chainplates. Iām replacing everything on my boat with new bronze. If you go this route beware of the proper measurements for holes. I am in no way shape or form an expert on thisā¦
We have not made a decision about which way weāll go yet, but Iām leaning towards bronze but I like both bronze and titanium above SS. In addition to not having any crevice corrosion issues (and therefore way outlasting me), the modulus of elasticity for both is lower than stainless. It probably doesnāt matter, but my thought is that in any extreme event (knockdown, etc.) the chain plates can stretch more and theoretically that should help reduce stress on the rest of the rig, possibly preventing the rig from coming down.
It seems there are a fair number of custom titanium manufacturers available, which should make that relatively easy (especially if you just send them all the old hardware). For bronze, Iād probably go through Todd to get a full set from PTF. I tried getting a replacement windlass handle direct from PTF and found them very unresponsive, but I suspect Todd would have good luck. Of course, you could send in the old hardware somewhere else, but I believe the bronze hardware has to be thicker.
For the record, we wonāt take CYMBA offshore until we replace the chain plates because I can see some hairline cracking in the ears on the gammon iron (no magnifying glass or dye penetrant required). I watch it carefully and Iām not concerned given the benign sailing we do on the Bay, but this is a āmust haveā for our big refit coming in about three years.
Apologies again for the delay and I hope at least something here is helpful.
Cheers,
Mike