Hull Fairing Question

[bjviking]

Hi.
I have built a 23 foot male mould hard chine boat I have just finished laminating it with 8 layers of 450 gm CSM with 417 palv resin Loyds approved) from Scott Bader. I am considering fairing it with U-Pol Polyester Filler Paste. Has anybody used U-Pol for as a Fairing paste, if so I like to hear your thoughts etc. I have used this before on a 17 foot run about, however this new boat will face more challenging elements as I plan to engine her to achieve 20 to 25 knots and am wondering if the filler will take the pressures etc.
Hope to hear from someone.

[Itchy&Scratchy]

Hey Viking

I wouldnt advise uPol simply because you will end up with so many voids to fill, sand the glass layer until smooth enough then put five layers of gel , letting it go off, in between layers. Make sure you dont leave too much time between layers as you will loose the crosslinking bond between the layers. Its best to add the next layer as soon as the underneath one has gelled.
On the final layer add 2% liquid wax to your mix, then add your catalyst and stir really well.apply that and leave to dry at least overnight.
The next day you should have a nice hard surface to work with. Sand with 180 grit on a DA sander and then you can go straight to 1000/1200 grit wet and dry. If you are using white gel get yourself a tin of black/grey guide coat. This is a powder spary formulation sprayed on in a tin which will allow you to see imperfection in your surface. If you are using a colour make sure that you mix enough colour for the whole 5 layer application otherwise you will have colour issues. The layers I have been described can be applied with a short pile gelcoat roller- replace roller after each layer. You can then polish with a machine polisher and 3m gelcoat compound.

I know it sounds like a shed load of work and it will be but youve spent a fair bit on the glass already by the sound of it so you might as well continue and do it right.
On the flipside you could fair the hull in epoxy and fairing compound, sand down and apply a few coats of epoxy- and then sand and spray two pack paint.
Have fun
J

[GG]

Once again i would use a a primer called Duratech it is a high build primer used in tooling and is good above and below the water line . I have used this primer for many years and works well on Epoxy and most of the boat co's i have ever worked for have used this including Skater . S 2 YACHTS , PowerQuest for repairs or tooling . Just my 2 cents .

[GG]

Sorry but you need to get your products from the good ole U S A , and im not trying to be rude .

[bjviking]

Thanks for your responses.
Plenty of ideas to think about.

Regarding the Guide Coat, I assume that when you see an area which requires to be filled, that you have to sand off the guide coat in this area?
On the Gel coat approach, any suggestions for a supplier of sprayable / brushable gelcoat with a good range of colors?

How hard is the Duratec High Build primer?
If it is easily sanded, would'nt that equate to easily scuffed and scratched?

If I went with duratec as the fairing option, and then coated the finished hull with a few coats of Gel, I would get the best of both worlds ie
Good omosis protection from both the Duratec and Gelcoat, and more scratch and scuff resistance from the Gelcoat

Regards.