Fibreglass bonding with Epoxy??

[Jabs]

Hi,

I need to fill a gap of approximately half an inch between the hull moulding and the coachroof/deck moulding.

It is a vertical seam about three inches deep and parts of the original filler have pulled out.

My initial thought would be to fill the gap with araldite with the intention that this would bond the hull moulding to the deck moulding and also provide a means of screwing on the toe rail and genoa tracks.

Does this sound a sensible approach?

Thanks

Tony.

 

[Graham_Wright]

Do you not have a rubbing strake?

My deck and hull were screwed together with (steel!) screws on arrival (bare hull) and were bonded inside by an "expert" (not me). Subsequently, mechanical strength was achieved by frequent through bolting with M8 A4 screws to penny washers on the inside. The gap I filled with mastic. Applied upwards, it was not a simple job.

 

[Jabs]

No. There is a toe rail that screws onto the top of the joint I an describing. The genoa track screws onto this and through it.

So the 'filler' takes the forces on the genoa track, hence it needs to be bonded securely.

Thanks

Tony.

 

[oldsaltoz]

Hi,

I need to fill a gap of approximately half an inch between the hull moulding and the coachroof/deck moulding.

It is a vertical seam about three inches deep and parts of the original filler have pulled out.

My initial thought would be to fill the gap with araldite with the intention that this would bond the hull moulding to the deck moulding and also provide a means of screwing on the toe rail and genoa tracks.

Does this sound a sensible approach?

Thanks

Tony.

Your big problem will the preparation of a 3 inch deep slot that's only half an inch wide. Without very good prep you could be lining yourself up for a failure. I would be looking for a clean surface with finish close to that left by a 40 grit sandpaper.

Araldite might work, adding some closed cell glass spheres would make it a stiffer and less likely to flow out or slump. At least it's an epoxy based product so bonding should be ok, I'm just not too sure how it will stand up to any flexing though.

Have you considered using an epoxy resin with a filler?

Good luck and fair winds.

 

[Graham_Wright]

No. There is a toe rail that screws onto the top of the joint I an describing. The genoa track screws onto this and through it.

So the 'filler' takes the forces on the genoa track, hence it needs to be bonded securely.

Thanks

Tony.

Are the screws self-tappers?

I would be inclined to use a metal strip drilled and tapped for maximum strength. Genoas can exert some mighty forces. If you use SS, there is a danger of crevice corrosion I suppose. As a belts and braces man, I would do just that and then bolt through horizontally. I had a foredeck lifted off the hull by a "helpful" matelot freeing my forestay from his landing craft (don't ask;- his fault not mine but well intentioned!).

 

[Jabs]

Are the screws self-tappers?

I would be inclined to use a metal strip drilled and tapped for maximum strength. Genoas can exert some mighty forces. If you use SS, there is a danger of crevice corrosion I suppose. As a belts and braces man, I would do just that and then bolt through horizontally. I had a foredeck lifted off the hull by a "helpful" matelot freeing my forestay from his landing craft (don't ask;- his fault not mine but well intentioned!).

Yes, ideally a 'sandwich' but that isn't possible.

The hull and the lip on the coachroof are both vertical and the rail screws to the top of the joint to both hide the joint and carry the genoa track.

The genoa track is alloy and very substantial. It has loads of screws so the load is spread a bit.

I think the idea of filled epoxy sounds best so far.

Thanks

Tony.

 

[Keith 66]

A diamond cutting disc or ordinary stone cutting disc on an angle grinder is good for cutting the old filler out, make sure its clean of dust & fill with west epoxy thickened with microfibres & silica.

 

[gjgm]

A diamond cutting disc or ordinary stone cutting disc on an angle grinder is good for cutting the old filler out, make sure its clean of dust & fill with west epoxy thickened with microfibres & silica.

Yes;you can get a small West System kit for about £15.
Once cleaned, apply some resin/hardener mix to wet the surfaces, then add your thickened paste (with silica etc). You can mix it thick enough so it wont run. Epoxy will really heat up if in volume, so you might want to part fill the repair, and then finish of half an hour later, but BEFORE the epoxy does set, or you lose some of the epoxy to epoxy chemical bond

 

[Jabs]

So it looks like glass sphere filled resin. I will clean out the gap with a rough file and angle grinder. Degrease with acetone.

Maybe push some soft rubber down the gap to seal it.

I believe I can buy some tubes ti fill so I can squeeze the mix into the gap.

Fill to top and clean off before it begins to set.

Maybe part fill if it is getting hot.

Other possibilities are to put in wood insets to take the screws since resin has a weak shear strength.

Any more ideas?

Thanks

Tony.

 

[oldsaltoz]

Other possibilities are to put in wood insets to take the screws since resin has a weak shear strength.

If you use resin and Micro-fibres at the joint the boat will break before the repair, use the glass spheres in fill only areas.

Good luck and fair winds.

 

[gjgm]

epoxy

So it looks like glass sphere filled resin. I will clean out the gap with a rough file and angle grinder. Degrease with acetone.

Maybe push some soft rubber down the gap to seal it.

I believe I can buy some tubes ti fill so I can squeeze the mix into the gap.

Fill to top and clean off before it begins to set.

Maybe part fill if it is getting hot.

Other possibilities are to put in wood insets to take the screws since resin has a weak shear strength.

Any more ideas?
Mask off the area and slop some runny resin in with a brush;dont be shy!Or thicken it just a tad. The idea is to get the repair "wet" and resin soak into anything porous. You then mix your paste to ketchup/mayonaise.. it wont run, so I dont think you need any tubes to squeeze it in, though you can cut a corner off a freezer bag and use like an cake icing bag if you like.
Epoxy resin is pretty fussy on mixing ratios, so take care there. It also is damn hard to remove/sand down, so mask off and wipe off extra or spills before it sets.
Get plenty of latex/nitrile gloves.. this stuff has a habit of getting everywhere, so changing gloves seems to happen more frequently than you might expect.
But otherwise, if you can butter a piece of toast, you can do this !
West Systems have some good brochures and tips online somewhere I think if you want the guru's advice!
Thanks