Cracks around chainplate

[tyce]

I have lots of little gel coat cracks around the area of deck that my chain plate goes through, never noticed this on any of my other boats.

Is it fairly common?

 

[kingfisher]

Aaaaarrrgh doom I say! Dooom! You're all gona die!

Uh, non, I don't know. I have a few similar cracks at the base of my chain plates, it comes with the territory of owing a 30-year old boat (A car that age, kept in the water wouldn't look half as good). My main concern is water ingress, so I pasted some epoxy on the cracks. I did however take a look at the chainplates inside the boat, and saw that everything is fine: no cracks where they are bonded to the hull, no water weeps. So its cosmetic.

One question: can your rig spanners move in both axis (are there two toggles on each spanner)?

As granddad used to say: "better a crack in your gel coat than gel co..."

 

[oldsaltoz]

After 30 years of involuntary jibes, preventer snatches and who knows what else I thing you can expect this.

If you are concerned and would like to check the chain plates to ensure the holes for the bolts have not rotted and elongated, do it.

If you want to ensure no water is getting into the deck, just grind the gelcoat off, mask the area and re coat with an epoxy that has some pigment added to get a close or contrasting colour.

You can even match the non skid dimples if think you need too.

Avagoodweekend......

 

[boatmike]

The gel coat is not structural and does not matter in itself. It does however indicate that the deck structure beneath it is, or has at some time, been flexing. This can be due to insufficient reinforcement inside the structure or someone doing the rigging up too tight. Inspect the inside (which may involve removing some structure or headlining). If what you find concerns you then make up a larger spreader plate to bolt the fitting through and bed it down on glass matt and resin. While you have the fitting removed you can grind back the gel coat and do a nice repair before bolting it back. If all looks well on the inside however leave it be and just dont do your rigging up too tight.

 

[vyv_cox]

In addition to boatmike's points, you may find cracking on many concave surfaces. This occurs because the boatbuilder goes to some lengths to ensure that there is plenty (i.e. too much) gelcoat here, as this is a notorious place for the gelcoat to be too thin. Bearing in mind that this was a convex surface when the boat was being laid up. Over time this thicker gelcoat tends to develop cracks, as it has low elasticity.

You may also see cracking on convex surfaces, because these were concave when the boat was being laid up and gelcoat may tend to slump into them.

 

[savageseadog]

I think that the traditional method of fitting chainplates is unsound. What you seem to generally get is a fixing to structure below deck with some kind of coupling attached to it through the deck with a cap plate which is often fixed to the deck itself. The problem with this is that the slightest easing or movement below deck will result in the deck plate pulling and lifting the deck. The resulting cracking isn't an issue except for water penetrating the chainplate attachment area but you should check for any structural failure of the chainplate below deck.
I've seen a yacht where the chainplate came right off, the rig and sails were lost. It was a big yacht and it was fortunate there were no injuries or worse.

 

[boatmike]

Depends what you mean by "traditional" At one time chainplates were invariably attached to the hull below gunwale level. Attaching to a horizontal deck was once unthinkable unless through to a substantial bulkhead or knee. The "modern" GRP practice of attaching to the deck alone is in my opinion structurally doubtful at best and without a substantial spreader plate under is a potential failure point.

 

[neil_s]

On my boat I also found that the deck around the chainplates was a GRP/ply/GRP sandwich. The plywood was sodden - but fortunately (mostly) not rotten.

Neil

 

[tyce]

Excellent replys, thanks to all.

Your opinions pretty much match mine, just required a bit of reassurance.
Like suggested i have checked where the chain plate connects to the bulkhead and then checked the bulk head to hull bonding and all looks as new as the day it was made.

Fortunately Parkers made it easy to access these places.

So i think the best course of action is a little bit of captain tollys and roll on the new season.

Thanks all

 

[Ariadne]

Doesn't matter what the chainplate is attached to if the cap shroud goes pop!!!!!

My whole port side chainplate assembly came through the deck! 25mm structural plywood, the deck plates, half a bunk and a waterproof speaker (that continued to work outside for the next 6 hours as we limped to Pwllheli).

Not bad for maiden trip in a new (to me) boat after an 8 month re-fit.