Using Adhesives to fit deck organisers

warwicksail

warwicksail

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I am about to fit organisers and clutches to the deck/coach roof, has anybody evry used adhesives for this I have access to all Plexus marine adhesives if they hold the hull and decks together for sunseeker im pretty sure they will hold,

Regrds Paul
 
Interesting idea! For clutches and organisers, shear strength would be important. As the High Strength Plexus adhesives claim 3000psi shear strength, they might do the job. Let us know how you get on.
 
How well is the gel coat attached to the GRP?

Sounds like 'can I put a shelf up with No-More-nails?'

It will be fine, untill you really load it up (the shelf or the organiser)!
 
'Some' have used Sikaflex to bong hull and deck, but I would not use it secure any deck fitting.

Keep in mind it will most likely fail when under the most stress, that's the same moment you need it in place most.

Avagoodweekend......
 
Will speak to the guys at marine industrial today (plexus agent) see what they think, its all about gap fill to allow exotherming (curing) of the adhesive , Also the surface should usually be keyed back through the gell. but some adhesive claim that no prep is needed.
 
For small clutches and heavily loaded halyards you could easily get close to 3000psi shear stress on the adhesive. In addition there will be tensile stress at one end leading to a peeling effect on the adhesive and tearing of the laminate below (due to tensile stresses perpendicular to the fibres). I would also have doubts about the bond to the metal underside of the fittings; they would need to be very clean and dry suggesting the need for an indoor work area. Add shock loads to all the above and I would be surprised if you could get it to work.
 
Why not add a couple of self-tappers just to be sure?

I would have thought most deck organisers are through bolted onto substantial backing pads though most of the shear will be taken by the deck. If bonding is an acceptable attachment I'm surprised that the budget AWB builders (you know who I mean!) have not already adopted the method for winches, cleats, keels, etc.. It must surely be cheaper than SS fastenings and take less labour.
 
I think this is a fairly daft idea. Fittings like this are not part of the structure and need to be fixed in a way which allows for maintenance, replacement etc. in due course. If the adhesive is strong enough to resist the considerable loads on deck organisers and clutches it's going to be pretty difficult to remove.

There are regular posts from people bemoaning the hidden fixings holding such hardware on the roof of various yachts. When someone asks how to remove a broken obsolete jammer from the coachroof 'which appears to be bonded with some kind of adhesive' I suspect the consensus will be to take an angle-grinder to the coachroof, cutting out the fitting, and then spend some time rebuilding the laminates to create a suitable base for fixing a replacement.
 
I would not have thought so.

The bases of organisers and cleats in particular have very little flat surface area to permit a good bond.

Perhaps mounting pads could be bonded to the deck but that really depends on the structure of the decks.

On my own boat I through bolted 30mm thick iroko pads for the cleats.

Then through bolted the organisers and even through bolted a pair of extra heavy duty Spinlock cleats.

I don't want them pulling off at the wrong time.

Iain.
 
In my professional life I have frequently been involved in reapirs of elderly equipment, working with specialist contractors. The best of these are very knowledgeable as regards adhesives, sealants, etc. In every case that I have been involved with we engineered the repairs using traditional methods, e.g bolting, clamps, patches, etc and calculated the strength of the repair to ensure suitability for purpose. Any sealants and ahesives were then included as a bonus, rather than the first line of the repair.

It seems to me that attaching critical fittings falls into a similar area. All my organisers and clutches are through-bolted, as I don't think self-tappers are adequate for this duty. I then add sealants, in most cases Sikaflex 291, to exclude water and to supplement the strength of the fixings.
 
On the spinlock deck organizers I have used then shaft og the pulleys are hollow to allow through bolting. Without this through bolting of the hollow pulley spindles the connection to the base is very weak and would not toke much load so even if the adhesive may hold the bast to the deck the pulley spindles would break away from the base in the spinlock design and may be other suppliers
 
I seem to remember this is in the WEST manual. Bonding of winches to deck structures. These would have been wood composites not GRP. Aircraft are routinely bonded together, but under finely controlled conditions. And they test all such stuff to distruction before putting in service. How many boats have you got to do that on? As said before, keep us informed, the eyes of the world are on you.
A
 
I suspect that the shear loads on my deck organisers exceed those loads. In addition the shock loads (the spinnaker collapsing and refilling in heavy airs) might see the clutches ripped from the deck?

Having said that, some boat builders use studs set in epoxy to mount winches. I only know that because one such boat builder advised me about setting studs into epoxy to mount and engine once upon a time. It worked very well, although the s/s stud took the shear load from the thrust of the boat.

When I remounted some clutches on our coach roof, I filled the old holes with thickened epoxy. Then removed the balsa from the sandwich construction where the new holes would be drilled. Filled those voids with thickened epoxy and finally drilled new holes through the grp-epoxy-grp sandwich. Then there was the matter of a large s/s backing plate and washers under the newly strengthened deck with sika-flex to keep the thing watertight. The clutches aren't going anywhere!
 
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I am about to fit organisers and clutches to the deck/coach roof, has anybody evry used adhesives for this I have access to all Plexus marine adhesives if they hold the hull and decks together for sunseeker im pretty sure they will hold,

Regrds Paul

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Good thread.

Consider this:

The Beneteau Group and Bavaria have some of the finest quality and cost process engineers in the marine industry. I have no doubt that their value team would have suggested all manner of fixing cost downs, and we havent seen this type of application, even on the notoriously fragile Vendee boats.

As I said, I await your report with much interest.
 
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the notoriously fragile Vendee boats.

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Considering the hammering they are getting, without a rest for 3 months, they must actually be extremely strong. It's the loads that are also extreme, surely? /forums/images/graemlins/smile.gif
 
I await your 2012 post which is:

How do you remove deck organisers adhesively fixed to the deck without causing extensive damage?....


Airbus and boeing may glue on the tail and wings, but not the remove/service items (the engines).
For my money, I'd go for the mechanical fastenings through bolting and use the adhesive to stick a large reinforcing pad to the underside of the deck and take the load from the huge washers used to spread the load.
The ability to remove for service/replace/ upgrade is important but fundamentally, I'd be worried about shock loading.
 
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