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Bill H

Unconventional pump boat part IX

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Bill H

Sorry for my delay in responding, I'm back in the States for a brief visit and busy here. The plywood is TuffPly and I purchase it through Vic's in Cebu. They are the best source of supply I've found. I wouldn't use any other plywood for boat building here. I'm going with a 8hp electric start, but I've hit a snag. The guy I purchased the motor from (new) may in fact be less than honest as the motor has yet to be delivered and it was paid for in December. That nightmare continues to unfold, but it's not looking good at this point. The cheap Chinese motors are just that and not worth the money. This is a been there, done that issue with me. So, at this moment in time, I'm not sure where I'll get the motor and may have to just wait until I return.

 

As for the Mitsubishi conversions. To be honest I've looked closely at them and I'm wholly unimpressed. Many things done by the builders here are penny wise and pound foolish and this is one example of that. There is a reason Marine diesels exist and are superior to diesels used in trucks. They simply work and last longer. Ditto marine gears vs truck transmissions. If your use is to be light and infrequent it might make sense, but if you plan on using the boat for extended periods I think it's a bad choice in multiple ways.

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Bill H

How would a jet drive work on one of these boats.

 

Jet drives are very, very fuel inefficient, so why would you want one in the first place? Of course if you have lots of money to spend on fuel then that's not an issue. However serious structural modifications would need to be made to the stern to accommodate the jet drive and forces involved. Certainly doable, but I doubt many local builders would appreciate the kind of force that jet pump puts out. You would also have issues with the water intake. The one thing you never want to do is run a jet boat in shallow water where it might pick up sand and rocks! As many of these boats are routinely beached, that would present a serious problem in my view.

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Bill H

Is this will be the boat with outriggers like majority of locals build? i never understood why would someone build such inefficient hull like most of the local banca boats have.

 

Well, I guess it depends on how you define "efficient!" If efficient is measured by fuel consumption, these very narrow hulls are very efficient. The long narrow hull form is always the best hull form for moving through the water with the least amount of energy to push it. Of course there is a cost to that hull form, and one of those costs (and in my mind one of the most serious) is stability. Enter the outrigger! They are there to keep the boat upright. Without them, the long narrow (very unstable) hull will turn over. With outriggers in place, the boat becomes very stable and very difficult to turn turtle....until an outrigger fails, then....well....it's not pretty. All multi-hull forms are inherently more stable upside down than right side up and this is true to the traditional banca design. When this happens at sea people frequently die. It's also why the design incorporates lashed outriggers as opposed to structurally integral outriggers. Since the lashings may be cut if the boat turns over and with one outrigger removed it's fairly easy to right the boat, re-attach the outrigger and continue...... at least in theory.

 

What I don't understand is why catamarans are not more common here. They would be as efficient as the banca, have greater stability in many cases and be able to carry greater loads. Yet I have yet to see one here. Go figure.

 

I have seen some very large banca's. Locally they are called "buffalo boats" and some are close to 100' long. The outrigger system on these banca's is a sight to behold too. What I don't understand is why they have not gone to mono-hull designs as the mono-hull form is significantly more stable, normally self righting and capable of carrying huge loads. You don't see them though and I'm not sure why? Maybe just tradition? I don't know.

 

In any case, we've started working on a 10m mono-hull fishing boat which I'm sure will turn some heads when we get far enough along that people realize what we're doing. I'll post that build if there is some interest in it.

 

Regards,

 

Bill

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Cuda

Well, I guess it depends on how you define "efficient!" If efficient is measured by fuel consumption, these very narrow hulls are very efficient. The long narrow hull form is always the best hull form for moving through the water with the least amount of energy to push it. Of course there is a cost to that hull form, and one of those costs (and in my mind one of the most serious) is stability. Enter the outrigger! They are there to keep the boat upright. Without them, the long narrow (very unstable) hull will turn over. With outriggers in place, the boat becomes very stable and very difficult to turn turtle....until an outrigger fails, then....well....it's not pretty. All multi-hull forms are inherently more stable upside down than right side up and this is true to the traditional banca design. When this happens at sea people frequently die. It's also why the design incorporates lashed outriggers as opposed to structurally integral outriggers. Since the lashings may be cut if the boat turns over and with one outrigger removed it's fairly easy to right the boat, re-attach the outrigger and continue...... at least in theory.

 

What I don't understand is why catamarans are not more common here. They would be as efficient as the banca, have greater stability in many cases and be able to carry greater loads. Yet I have yet to see one here. Go figure.

 

I have seen some very large banca's. Locally they are called "buffalo boats" and some are close to 100' long. The outrigger system on these banca's is a sight to behold too. What I don't understand is why they have not gone to mono-hull designs as the mono-hull form is significantly more stable, normally self righting and capable of carrying huge loads. You don't see them though and I'm not sure why? Maybe just tradition? I don't know.

 

In any case, we've started working on a 10m mono-hull fishing boat which I'm sure will turn some heads when we get far enough along that people realize what we're doing. I'll post that build if there is some interest in it.

 

Regards,

 

Bill

 

First off, thanks for updates

I meant efficient as a ratio of material used and buoyancy achieved. Just like some man powered coastal New England and Euro designs .Ii have build many of those and small fishing boats and they were gliding easily were comfortable to move in around and carried heavy loads.

Completely agree with you on the catamarans/trimarans.

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pakrat

What a Great Build! Looking forward to following your progress when you get back, and wish you luck with the engine. i have a few questions about your running gear, but i'll wait until you get back and find out if you have any running gear before bothering you...

 

Will you be putting the "big bend: into your akas (outriggers) in the tradition of the local practice? i admire the flex the system has, but wonder how the bend is done. Steaming perhaps? You said that you will be sealing the bamboo amas (floats) with epoxy and coating them with anti fouling paint. Will there be any fairing to the ends?

 

Good luck and hope you can get back to it soon, she looks like she wants to taste the salt!

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JamesMusslewhite

How would a jet drive work on one of these boats.

Water-Powered-Jet-Aircraft-for-Water-Sports_tmb.jpg

 

bit hard to fish though.......

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Bill H

Water-Powered-Jet-Aircraft-for-Water-Sports_tmb.jpg

 

bit hard to fish though.......

 

I think that would be a heck of a drive unit James, but the 150HP motor powering the pump would be a bit taxing for the boat to carry, don't you think? LOL I'm not even going to address the liters per minute fuel consumption though! LOL

 

I'm back by the way!!

 

Bill

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Bill H

Like MacArthur, I have returned! LOL

 

Still no motor, lots of excuses, but no motor. I hate it when folks aren't ethical, ya' know? Anybody looking to buy motors, fishing equipment, almost anything from Negros, talk to me first!

 

Bill

Edited by Bill H

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Bill H

First off, thanks for updates

I meant efficient as a ratio of material used and buoyancy achieved. Just like some man powered coastal New England and Euro designs .Ii have build many of those and small fishing boats and they were gliding easily were comfortable to move in around and carried heavy loads.

Completely agree with you on the catamarans/trimarans.

 

My biggest problem with the majority of the local builds is the lack of freeboard. I've seen boats on the bay with less than 4"! Three guys paddling and one guy bailing like mad. Yes, maybe they are light, but safe? I don't think so!

 

Bill

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Bill H

What a Great Build! Looking forward to following your progress when you get back, and wish you luck with the engine. i have a few questions about your running gear, but i'll wait until you get back and find out if you have any running gear before bothering you...

 

Will you be putting the "big bend: into your akas (outriggers) in the tradition of the local practice? i admire the flex the system has, but wonder how the bend is done. Steaming perhaps? You said that you will be sealing the bamboo amas (floats) with epoxy and coating them with anti fouling paint. Will there be any fairing to the ends?

 

Good luck and hope you can get back to it soon, she looks like she wants to taste the salt!

 

Yes, our akas have the big bend! It's not that hard to do, but you need special bamboo to do it. Basically, you build a fire, heat the bamboo and apply constant pressure in the form of a rock suspended from the bamboo to be bent. You don't want the fire so hot it buns the wood, but hot enough to make it pliable. If I were going to be doing this a lot, I'd probably build some kind of steamer to do the job, I think it would work better. Due to the high freeboard on this boat, we have pretty good bends. Once we've solved the paid for but not delivered motor problem, we'll attach the outriggers and you'll see how extreme the bends had to be.

 

Bill

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Cuda

My biggest problem with the majority of the local builds is the lack of freeboard. I've seen boats on the bay with less than 4"! Three guys paddling and one guy bailing like mad. Yes, maybe they are light, but safe? I don't think so!

 

Bill

exactly , not enough inside volume, no load capacity, local design just plain sucks.

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pakrat

Thanks for the info on the "big bend". Sounds like you will be steaming using the internal moisture of the bamboo. On the bent amas that i have looked at i see that a "relief" is cut in the bamboo, perhaps 50% of the diameter. I am surprised that this would leave sufficient strength, but then bending a full diameter bamboo stalk would be rather like bending a soda-pop straw. Bamboo is neat stuff that i won't even begin to pretend i understand.

 

i am pretty sure that the lack of freeboard is another hold-over from the pre-pump engine days, low freeboard meant you didn't have to reach down as far with your paddle. But even in those old canoes it was a good idea to have a designated bailer if the electric pump gave out. (That is, if you didn;t want to simply cut a hole in the bottom of the boat to let the water out...)

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ernesto

Like MacArthur, I have returned! LOL

 

Still no motor, lots of excuses, but no motor. I hate it when folks aren't ethical, ya' know? Anybody looking to buy motors, fishing equipment, almost anything from Negros, talk to me first!

 

Bill

i'll keep these in mind.

i'm wanting a 15-17footer pumpboat. how much? with/without motor

my wife is from san carlos city. cross it to negros from moalboal? hahaha

we go home every 2 years.

plan to retire at 50~54. i'm 44 now. 

thanks.

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ernesto

and where's the pics of the finished product?

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Thelandofku-an!

 

Theft is a problem here.Before you get a boat, you have to have a secure place to keep it or a guard on it. If you don't, things will disappear

 

Also on moorings in Poole Dorset UK, leave a big outboard securely bolt-locked to the transom and the creatures would just chainsaw the transom off!

 

So many nice boats vandalized for the theft of masts and booms too, grr!

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