Fitting Mooring Cleats

[Stemar]

My old boat, a mono (now I'm a cat owner, I suppose I should call her a half-boat) sat happily on my mooring with a single chain, but Jazzcat's a Catalac, 8m long and 4m wide and about 6 tons. I know from having had one on the next mooring for a while, that she's likely to sail around the mooring, so I want to use two strops, one to each hull. However, the mooring cleats aren't in the best place for that, so I'm thinking about fitting cleats in the right place, which will also help at anchor. Access is awkward, but not impossible.

Plan A is to take a lump of 18mm ply about a foot square, slather it with thickened epoxy and squish it up under the deck, then add a couple of layers of glass cloth to seal it. Once all that's gone off, drill my holes oversize, fill with thickened epoxy and drill to the right size, then bolt down with big penny washers or, perhaps better, a lump of stainless plate.

Any thoughts? What have I missed?

Thanks.

Off to the boat shortly, so won't be back here for a few days - I'm not ignoring you!

 

[Boathook]

I would drill a small hole to see the thickness of the layup. On some Catalacs it was uneven so reinforcing a waste of time imho.

 

[C08]

Mine and most Catalacs I have seen have a cleat each side just astern of where the rear pulpit mounting meets the deck on each side. I fitted fairleads for my mooring bridle at the front a couple of feet inboard on each side. I would agree that the layup is erratic in places.
You will have more difficulty getting the right place for a windlass so that the anchor chain has a clear fall into a side locker. Mine had the windlass with the chainfall into the centre locker, all10" of depth so it just piles up.
I have a Catalac cleat you are welcome to have (black anodized about 10") if you are trying to match up with an original.

 

[Ceirwan]

Technically if the deck is balsa cored then the balsa should be replaced with a more solid core like plywood in way of the cleat.
Kind of hard to afterwards though without a big project.

I would go with your plan, oversize holes filled with epoxy, these if done right should stop you crushing the core, but I would use G10 or aluminium as the backing plate, 18mm would be overkill. Off the top of my head I think in elements of boat strength its recommended the fastener diameter x 1.5 for the backing plate thickness.
Whatever you use, it will be a lot more effective if you squish it with epoxy (as your original plan).

 

[William_H]

I imagine you are thinking of mooring cleat centre fore deck. In fact I think best location woould be on or near the gunwhale where typically a GRP hull has the deck and hull joining making a very lay up just right for through bolts. Also the chance of the mooring rope going over the side to the mooring not needing fairlead. On the other hand not so easy to amke a backing plate. ol'will

 

[zoidberg]

Round the corners of your ply pad with a large radius, and chamfer the top edges all round. This reduces the likelihood of stress concentrations and cracks.

 

[howardclark]

Fair leads too?

 

[Neeves]

Our pulpits have 3 legs. The first is just behind the bow, outboard and the mooring cleats are at the apex of the curve of the 'top' of the bow - its near semi circular in section and ahead of the middle leg, which is inboard.

We were not confident in the reinforcing and added a glass pad to the existing glass and filled it out till roughly flat and then an extra layer of glass on top. The glass was 750gram.. We used 10mm aluminium backing plates predrilled, to match the existing aluminium cleats. Our bow in that area is all glass. The mooring bridle does not touch the gelcoat, the cleats are luckily sufficiently inboard. We have a prodder and we reinforced the bob stays at the waterline the same way - except we did not need to fill out as the hull in that location is flat.

We also have a single central mooring cleat - we can then release the mooring cleats on each bow and we sit then head to wind. If you do not have a central mooring cleat when you release one you immediately lie across the wind (whether you have sails set or not).

Our bows are quite narrow - once you get into them you cannot turn round. You thus need to position your self to do whatever work is necessary but you need someone else, the skipper is perfect, who can pass the a preloaded brush, wetted out glass of the right size, roller etc etc - it needs careful planning and complete understanding of what is being done. You need to make up the resin, wet the glass, make the filler in advance , have it all laid out on a tray and then complete the task in one easy sequence. Once it cures you can then drill, fill the filled hoes, or whatever and bolt the aluminium plate, inside, to the cleat on deck

Jonathan