Chain plates are out, now what?

[jrd22]

I've taken the chain plates out (well, almost)of the new to me 1988 Brewer 40 per the surveyors recommendation and I'm wondering how I check them, or where I take them to be checked for cracks, corrosion, etc. They look perfect, bright and shiny and smooth, but they are 20 years old (I think). Should I just have new ones made and not have to worry about them, or if they check out OK are they as good as new? I'm in Anacortes/Seattle area. Thanks, John

[Brion Toss]

Hi there,
First, I am glad you took the surveyor's recommendation; we often have difficulty convincing clients to remove their chainplates for inspection, even though about a third of all dismastings are due to chainplate failure, usually due to damage that is invisible when they are in place.
Your chainplates, at about 20 years of age, are prime candidates for an inspection.
"... perfect, bright and shiny and smooth ..." sounds good, but as it happens chainplates and other stainless items can look wonderful to the naked eye, and particularly to the untrained eye; you need magnification to be certain, and to know what you are seeing through the scope. There is a good chance that your chainplates are completely fine, especially if the original quality was good, the dimensions correct, the relative loads as designed, the tune somewhere near right, the climate the boat has lived in mild, and the installation done right. But of course, that's a lot of if's .
As it happens, I am very good at looking at chainplates, so my shop is one option. You might also check with Lynne Reister, my favorite surveyor. She's in Seattle, or with any qualified metallurgist. I always try to avoid throwing away gear because of uncertainty about its condition, but if you can't get a definitive answer from somebody, replacement could be cheap insurance, assuming that the new plates are made and installed correctly.
Fair leads,
Brion Toss

[jrd22]

Thanks Brion,

I posted this same question over on Sailnet to see what responses I would get. Almost all are asking what the surveyor was thinking requiring removal and inspection of the plates. If you can give me a yay or a nay on the plates I will send them over to you to inspect. It might be a couple of weeks, they are unbolted but I have to wait until the boat is under cover before taking them out. I read the other posts on chainplates here before posting and bronze was recommended (mine are stainless), would this be your recommendation if they need to be replaced? I did not take the bow fitting off as it is fairly massive and part of the whole anchor roller assembly, does this need to come off and be inspected as well (pin fits tight)?

Thanks very much, John

[Matthew Sebring]

I second Brion's thoughts on thise. I've personally sailed aboard a boat that lost one of it's chainplates. This was a Merrit 25 with the plates passing through the deck and above and below decks they looked but right where they passed through they'd rotted away. The rigging shop I used to work at had a very large bin full of chainplates so far gone that most i'd be able to break with my bare hands. Crevice corrosion is an amazingly destructive but, to the untrained eye, difficult to spot thing. Most people just assume that chainplates are forever (hence the mixed advice you're getting) but that's simply not the case. Worst case scenario at this point is that you've wasted a little time and effort removing the old ones, on the other hand worst case scenario for not pulling them is missing a bad plate and losing your rig. An ounce of prevention.