Fitting a spinlock triple clutch?

[Richard_Peevor]

Good morning.

I cant get onto my email account to email the spinlock support department so I thought I'd try here.

I have two sets of spinlock clutches to fit to my GRP coachroof to replace tired, old clutches of uncertain brand.

I know what size bolts to use and I will bed it in sealant but I am uncertain as to what should be on the otherside of the deck? a normal washer and nut (?nyloc), a repair washer and nut or a more substantial backing plate? /forums/images/graemlins/confused.gif

I suppose with 6 bolts and a lateral forces to them it shouldnt rip out of the deck... BUT.. I'd rather get the experienced advice before I risk doing major damage to the boat or anyone standing infront of the clutches!!!! /forums/images/graemlins/frown.gif

Many thanks in advance,

Richard

 

[simonfraser]

if your deck is solid grp, easy, 20ish mm diameter penny washers on the inside and off you go

as the old ones didn't pull out of the deck, use the same system

 

[Richard_Peevor]

Thanks simon, thats what I was hoping the answer was. I havent taken the headlining down and wanted to be prepared prior to going to boat rather than going down, assessing and possibly having to rethink!

Many thanks

Richard

 

[savageseadog]

If the deck is sandwich construction you should replace the core with something solid. What I do is drill the fixing holes then use a hole saw about 20-25mm diameter to drill out the underside of the deck leaving the deck surface in place, Then fill the hole with solid epoxy.

 

[jerryat]

I have two banks of three Spinlocks on each side of the main hatch on my Fulmar (12 lines in all) and went through the same 'chin-scratching' as you before fitting them.

Even though the existing (fewer) clutches had just been backed up with penny washers, I decided to use a 3mm aluminium backing sheet across each bank of two triples to give a larger area for load distribution.

The aluminium was bent very slightly to follow the camber of the deck underside and was bedded in epoxy filler. Once in place I just drilled from the top as usual.

It's never moved and there is absolutely no deformation of the coachroof. Just an idea.

 

[Phoenix of Hamble]

I also backed mine with 3mm aluminium plate...... they're under a lot of load on occasions...

Depends I guess, as said above, what deck they are going into... if its a foam sandwich, then i'd definitely put a plate in....

 

[savageseadog]

Anither reason for cutting the core out and filling is to prevent moisture ingress

 

[fdmarsden]

On a previous boat, I had the opposite problem, the headling was grp, with no access hole to the balsa cored coachroof.

Solution, drill out the outer lamination and core of the coachroof, but not the inner lamination or the headlining, again about 1" dia.

Make a rod of solid grp the same diameter, recess the balsa back a little, and epoxy the rod in.

File flush.

Drill and tap the rod and fit the rope clutch.

It is only necessary to do this for the rearward holes, the forward ones will hold with a self tapper, as the load on the rope clutch is always forward, therefore pressing the forward end down.

Never had any problems with this method.

 

[Norman_E]

There is a warning in the instructions for the clutch I bought not to use Sikaflex 291 to bed it in because it is incompatible with some of the materials used in the clutch.

 

[CodStewart]

Fitting a spinlock triple clutch?

Tee hee. I love boat lingo.

 

[Richard_Peevor]

Thank you all... I had forgotten about the foam sandwich.. why is anything boaty never straightforward!! praying the deck is solid..

If you are using epoxy to back fill as per savageseadog would it stay in a 25mm hole above your head? or do you need something to mould the shape?

Could you use epoxy filler instead of epoxy?

Could you use a backing plate as otherwise stated instead of building up with epoxy?

Thanks codstewart !!!!!!!!!!

Thanks for all the help.

Richard

 

[Oldhand]

Mine is screwed into a moulded in 5mm Al backing plate, the nuts and washers are just belt and braces

 

[bilbobaggins]

[ QUOTE ]
Tee hee. I love boat lingo.

[/ QUOTE ]

Pervert.... You cunning linguist, you!

/forums/images/graemlins/grin.gif

 

[savageseadog]

[ QUOTE ]
Thank you all... I had forgotten about the foam sandwich.. why is anything boaty never straightforward!! praying the deck is solid..

If you are using epoxy to back fill as per savageseadog would it stay in a 25mm hole above your head? or do you need something to mould the shape?

Could you use epoxy filler instead of epoxy?

Could you use a backing plate as otherwise stated instead of building up with epoxy?

Thanks codstewart !!!!!!!!!!

Thanks for all the help.

Richard

[/ QUOTE ] I mix my own filler with west epoxy and colloidal silica or whatever. By all means use a backing plate, whether it needs one or not depends on the strength of your deck. I have seen fittings pull right through a deck so it can happen.