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Bill H

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Bill H

If as you say you are building strong workboats why not use some woven fibreglass on the bottom sides?

 

As for epoxy paint what do you see as the great advantage?

 

I talked to a Cebu expat who has owned a number of banca boats and known a lot of expats who have owned one, he maintains that a lot of guys make the mistake of trying to Westernize the banca and by doing that add to the cost and introduce numerous extra items that fail or require more maintenance. He advocates using House paint for the hulls but to haul out the boat regularly and recoat at least annually. His concern with using coats of epoxy over the wood is that it prevents the wood drying out if there are areas that are breeched and become water logged.

 

One thing that worries me with native built bancas is that they are not built with any watertight flotation compartments..........some may argue thats not necessary when you have bamboo outriggers.

 

Sorry for all the questions, I am interested in building my own boat sometime and this is a great oppurtunity t learn

 

Thanks

Ricbak

 

Oh my, where to start? Fiberglass is not water proof. Most folks don't know that, but it's not. This is why so many fiberglass boats have blistering problems. Glass over plywood has some advantages, but also some disadvantages. It's a tough call in my view. Also, I've never liked the way fiberglass smells. We all have our quirks I guess.

 

Flotation. I once knew a guy who built a steel boat, he filled the bilges with spray in foam so it would be "unsinkable." Then I showed him the math. To keep the boat just even at the water's surface would have required 2/3's of the boat filled with foam! Not practical. One of the reasons for this is most mono-hull boats carry a lot of balast. in his case over 15,000 pounds. It takes a lot of flotation to counter 15,000 pounds of lead.

 

Enter the Banca. No ballast, the boat is made out of wood, the wood floats. Even the paint that is coaing the wood has a small amount of buoyancy. So, when (if) the boat is flooded, it should still float. Of course if you've mounted a huge engine, it might not, but most of the engines in Banca's are small and don't weigh very much and it's also true tha bamboo has a little more buoyancy than wood. Of course, none of this would be true if you build the boat out of iron wood which has negative buoyancy, but I've never seen anyone do that. In any case, the boat should pretty much float just at the surface in saltwater. At least in theory.

 

Air filled flotation chambers are truly problematic because even a small leak renders them useless. So in our time flotation chambers are filled with closed cell polyurethane foam. You have to subtract the weight of the foam from the potential buoyancy, but foam is not extraordinary heavy. However, once the chambers are filled with foam there is no getting behind them, no painting can take place. Thus even a small amount of water could be present and that's all you need for rot to set in. We're I going to add flotation, I think I'd be more inclined to cast some foam blocks and build a structure to hold them in place such that they were removable for maintanence. Now that would not be hard to do. A cubic foot of 4# foam would give you about 58# of buoyancy. If you're boat weighed 300# you'd need 5.17 cubic feet of foam to insure the boat would not sink. 5 cubic feet would measure 5' long by 1' wide by 1' deep. Put that in the bottom of your Banca and there isn't much room for a lot of cargo, ya' know?

 

Like many things in life, boats are a combination of compromises. You pays you money, you takes you chances!

 

Regards,

 

Bill

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Bill H
I talked to a Cebu expat who has owned a number of banca boats and known a lot of expats who have owned one, he maintains that a lot of guys make the mistake of trying to Westernize the banca and by doing that add to the cost and introduce numerous extra items that fail or require more maintenance. He advocates using House paint for the hulls but to haul out the boat regularly and recoat at least annually. His concern with using coats of epoxy over the wood is that it prevents the wood drying out if there are areas that are breeched and become water logged.

 

Yes I've heard this too. Actually, I'm going to build some test panels and test this theory as soon as we get moved to our larger yard. My expectation would be it would do pretty good in some areas, and not so good in others. Any time you paint, surface preparation is the key. Poor preparation = poor performance. That's just the way it is regardless of the brand of paint you use.

 

I've used close to 25 gallons of epoxy paint here now. We've used both the Pioneer and Cord brands, I don't see a great deal of difference between them. I like the Pioneer Yellow much better than the Cord, so that's what we use a lot of. Both brands have the same consistancy after they are mixed. Thus far I am not particularly impressed with either brand. State side I've been using Ameron epoxy paints for years, but it's not available here. There is a huge difference between the Ameron paint and the local brands. Both of the local brands are very watery in consistency. The Ameron is very thick, like very thick cream. Coverage on the Ameron is one coat, except when you're wanting to build up some thickness, but one coat covers very well. Not so with these local paints. Two coats minimum, probably three to get a good looking job.

 

Ameron wears like iron. I've even used it to paint length indicators on anchor chain and it held up for over three years. That's tough paint! These local paints don't hold up nearly as well. As you can see from the pictures I posted, this boat was only used for 8 months and it looks very bad for so little time in the water. So, would latex house paint hold up any better? Maybe, I'm certainly going to give it a try and see what happens. I'll keep you posted.

 

As for epoxy preventing the wood from drying out.... well, perhaps, but then if you apply it correctly the wood would never get wet in the first place! The West System championed by th Grudgeon Brothers has been around for a long time and has an excellent reputation. In that system all surfaces are coated with a coat of clear epoxy prior to joining or painting. If it works there, it should work here.

 

While I'm critical of the local paint, I'm pretty happy with the laminating epoxy I've tried. It's worked well for me so far.

 

Bill

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