Securing Organisers and Clutches to the deck

[cpedw]

I plan to install a triple clutch and organiser like these from Barton to the fibrglass deck.
The clutch has two bolt holes per clutch, that's 6 in all. Does it need a 6mm bolt in every hole or will it be happy with 4 in the corners?
The organiser has 3 fixing holes, one through the centre of each sheave. Similarly, I wonder if it needs 3 bolts or would two be adequate?
These will be securing slab reefing lines so only one line would ever be under tension ( unless things have gone spectacularly wrong).

I get the impression that they are modular construction so, for instance, the single, double and triple clutches are all made from the same parts, just rivetted together in groups hence all the holes are there for manufacturing convenience. Or do you think they really need my deck to resemble a Swiss cheese?

Thanks,
Derek

 

[Phoenix of Hamble]

The loads can be pretty high.... I'd personally be looking to use all the mounting holes....

 

[pvb]

Use all the fasteners...

You should ideally use all 6 fastener holes. I fitted a triple Spinlock clutch, and the instructions specifically said to use 6 fasteners.

 

[asj1]

Use all bolts holes and put a s/steel plate under the deck. Have eone made up with 1mml arger holes to allow for any slight errors when drilling through the deck. Consider making up a jig to ensure you drill vertically through the deck - not easy on a slightly curved decK. I used teh two s/steel plates attached to ablock of decent wood through which I had drilled vertically with a pillar drill. Worked a treat !

 

[oldsaltoz]

G'day Derek,

Use all securing holes, Swiss cheese looks a lot better than ripped deck anyway.

To add to the strength and prevent water ingress drill the holes 10mm over size and fill with resin and Micro Fibres (Not balloons).

If it's a foam cored deck cut out some of the foam between the deck and under layers of glass before filling and re drilling.

Fit a stainless backing plate with well rounded corners and both top and bottom edges, bed this in on more micro fibres and resin mixed to a toothpaste consistency and look forward to many years without mounting problems.

Hope this helps,

Avagoodweekend......

 

[Topcat47]

Only one thing I'd add to the previous post, if you have a curved deck, don't be tempted to use the new fittings as a drilling template for the backing plate, the hull thickness will bugger-up the alignment of the holes. Deburr the plate as well as rounding off the corners.

I'd also drill and tap the holes, it makes then easier to seal with a little bit of silicon. Tighten them as best you can, then do up the nuts underneath, but I'm not a professional like Oldsaltoz, so belt and braces makes up for my lack of skill.

 

[chewi]

Make an interface plate in eg teak and temporarily bolt that thro the deck.
Then fix the clutches to thatand refix the teak plate. In years to come you will change the hardware and have less holes in the deckhead.
Less holes diminishes likelihood of leaks & makes less of a mess of te headlining too.
I have 7 lines to clutches each side, using all the clutch fixings but only 4 bigger fixings each side thro' the deck. It Held out in F9.

The clutch bolts are mostly in shear, not tension, compare the strength of your fixings with that of the pins in the shackles etc. I would use all the fixing holes if I could, but not sweat about it if one was unusable.