UPDATE: My chainplates is epoxied into the deck!?

KompetentKrew

Well-known member
Joined
27 May 2018
Messages
2,437
Visit site
To recap, see my last thread: My chainplates as epoxied into the deck!?

As per that post #6 of that thread, all chainplates need inspection, at least, due to obvious evidence of water ingress, and because one of the chainplates failed during a gale, whilst the boat was on the hard.

I don't really like cutting into the deck, so I started out by procrastinating a bit. By my standards it's a miracle that it's only a week since my last post.

In the below pic you can see a cut that's about 1mm from the chainplate - for the benefit of anyone else in this position, it seems better to go downwards rather than up. Or maybe work 50:50, but try not to go all the way through from underneath - it was much easier to line up the multitool blade going downwards next to the chainplate:

IxmPKQC.jpeg

Having made these cuts on all sides of the chainplate it was obviously lose, and came free pretty easily with taps from a mallet.

The weird thing is that I'm still unable to remove it because it's too long - the foot of the chainplate is only an inch or two from the hull, and the length that goes through the deck is longer. So it was easy to tap it though, until the point at which the butt butted up against the hull, and then it's trapped.

The below photo shows the chainplate as far down as I can withdraw it - it's now stuck because it can't move down and it can't move sideways. You see the sort of backing plate, below the deck and at the top of the photo, that is holding the chainplate in place? My best guess is that the chainplate was put in place with that loose around its neck, and the backing plate was only epoxied into place once the chainplate was fitted.

0aiLNDI.jpeg

I tried to take clear photos from both sides, because my initial reaction was to ask if it looks ok enough for me to just put the existing chainplate back:

QzTUIhl.jpeg

cubnVtB.jpeg

reqU5oh.jpeg

I did also think that I could cut it out and make a replacement chainplate an inch or two shorter - I think it's secured with 5 big bolts, but probably 4 would be fine.

I have since realised that I don't need to - removal is only a problem because of the stainless steel tube in the middle, because this prevents the chainplate from being drawn out through the deck. If I cut out this existing chainplate then I can just use 35mm x 5mm plate for the whole length of the replacement chainplate and it can be slid in from above. That is my current state of thinking, at least, but I would be grateful for the committee's thoughts.
 

KompetentKrew

Well-known member
Joined
27 May 2018
Messages
2,437
Visit site
Video I recorded before this last line of thinking occurred to me:


It might show some details that I've overlooked in the photos above.
 

chris-s

Well-known member
Joined
24 Apr 2019
Messages
684
Visit site
It looks like with some careful use of a dremel you could trim away some of the backing plate enough to allow the chain plate to slide out, but photos can be deceiving.
Our Beneteau has something similar but uses a large turnbuckle where you have a tube so could be split. But if you are going to remake something then a straight forward flat chainplate as you describe is probably the easiest option.
 

vyv_cox

Well-known member
Joined
16 May 2001
Messages
25,866
Location
France, sailing Aegean Sea.
coxeng.co.uk
The fundamental cause is the use of epoxy as a sealant, doomed to failure where even the slightest movement occurs. Slight water seepage has led to corrosion cracking at the rather dodgy looking weld. Replacement with flat bar seems to be a far better arrangement and it is difficult to imagine why they were made like that, surely not by the builder?

When replacing use Sikaflex 291 or similar to bed the chainplates into the deck and for the cover plates.
 

KompetentKrew

Well-known member
Joined
27 May 2018
Messages
2,437
Visit site
… it is difficult to imagine why they were made like that, surely not by the builder?
I think they are original - the boat was built by a very small owner-operated jachtwerf. It was one of the first big boats he built and, at the time, the jachtwerf was a shed in his back garden. The boat has certain idiosyncrasies.

A number of people have commented that flat bar would be less attractive - I don't care, and I'n not sure I even agree, but presumably that's why the tube was chosen instead. This chainplate secures the shortest of the three shrouds, which attaches to the mast just below the lowest spreader. So I guess it's under least load?
 
Top