Gelcoat rubbed off stem on Boston Whaler

[Superaquarama]

Hi Guys,

Our Boston Whaler Supersport 15 has a pretty good hull, but where she's been run up beaches etc. over the years the Desert Sand gelcoat has rubbed off the lower stem and front couple of feet or so of the keel.

I fondly imagine that the GRP is 2 or 3 inches thick there anyway, so hopefully it's just a cosmetic issue, but I think I'll re-gel it anyway to be on the safe side.

Question is, though, is there any permanent fix to prevent this recurring ? If this were a wooden boat I'd just screw a brass strip in place, but with a GRP foam sandwich hull this may not be such a good idea. Is there any überglue that might hold such a strip in place, or anyone have any ideas ?

Thanks,

Tony

 

[oldsaltoz]

Hi Tony,

I would simply add 4 layers of 450 gram cloth with epoxy resin, start with a narrow strip and add 50 mm to the width to the next till all 4 are on then paint over the area with 3 coats of flow-coat (gel-coat with wax added).

Keep an eye on it in future nd just apply flow coat when you see any sign or the new class.

Re coating only takes a few minutes and dries quickly.

Good luck and fair winds.

 

[gjgm]

Hi Tony,

I would simply add 4 layers of 450 gram cloth with epoxy resin, start with a narrow strip and add 50 mm to the width to the next till all 4 are on then paint over the area with 3 coats of flow-coat (gel-coat with wax added).

Keep an eye on it in future nd just apply flow coat when you see any sign or the new class.

Re coating only takes a few minutes and dries quickly.

Good luck and fair winds.

I wouldnt use flowcoat as surely the wax stops the next layer bonding... just use gelcoat.In fact if it is only the gel that has been worn away over the years and no grp, I wouldnt bother building up the grp that isnt missing anyway !
Just slap on some gel.

 

[antaris]

As far as I know, Boston-Whaler GRP is actually quite thin (nowhere near 2-3 inches), since the whole sctructure relies on the double skin forming around the foam core. Calculate a reasonable thickness for a boat hull, divide it in half and place each half on either side of water-absorbing 3-4-5 inch thick foam... that's what you get on a Boston!

I would, therefore, grind to get clean material, apply a bit of epoxy resin and then tan gelcoat. It is important to keep the water out!

For added protection, I'd add something like KEEL GUARD (either buy the peoduct or just glue some rubber profile to keels!)

Have a look at this 1977 Revenge that I almost bought a few years back - the keel has rubbed heavily on the trailer and the foam is showing through the GRP! I know this is a little extreme, but it shows the thickness of material, even on a 23 foor monster!

 

[Superaquarama]

Many thanks for the quick responses, everyone.

I realise of course that the whole hull isn't 2" thick, Antaris, but I'd assumed that the keel bit might be, to allow for just this sort of chafing etc.

But that Keel Guard seems to be exactly what's needed, so I think I'll firstly repair the gelcoat and secondly fit the guard, which should then be at least a semi-permanent solution. If necessary I can put some cloth & resin first, but from a quick look that shouldn't be needed; as gjgm says, there's little if any loss of actual grp anyway.

Thanks again,

Tony


P.S. Just spoken to the UK Keel Guard people, very helpful. Seems a bit expensive for what it is @ £155 or so but apparently lasts for years if properly applied, so seems a good and worthwhile solution and has been sold to the RNLI since the '90s.

 

[oldsaltoz]

I wouldn't use flowcoat as surely the wax stops the next layer bonding... just use gelcoat.In fact if it is only the gel that has been worn away over the years and no grp, I wouldn't bother building up the grp that isn't missing anyway !
Just slap on some gel.

Hi Gigum,

Flow coat is Gel coat with wax added and all ends up on the surface just like any normal resin, it saves you having to cover it with plastic till it sets. There is no contamination.

Good luck and fair winds.

 

[antaris]

wow, that's a bit dear.... maybe just stick on some rubber profile (you've got 3 keels!)

 

[Superaquarama]

Yes, that price is for the minimum 6ft length, standard colours are black or white, but others are available to special order from the US, where it's made. I imagine half the price is for the special adhesive system, which is obviously very effective.

 

[rob2]

If aesthetics are important to you then all you can do is periodically make good the surface with gelcoat (flowcoat) or epoxy, which will be a little tougher. If you really want to improve its abrasion resistance there is a method used on whitewater canoes. A patch of Kevlar is laminated over the area and, strangely enough, it make them pretty much bullet proof! Of course, this sh+t brown patch looks awful but maybe you could paint over it.

Rob.