Has anyone made their own third pontoon?

[DMAN1968]

Hello all,

I was looking into some options for my 24 foot pontoon boat and came across the website for the Pontoon Water Glide (www.pontoonwaterglide.com). I have a few questions concerning the third potoon idea:

1. How does a third pontoon that is identical to the other two help performance when it is still such an inefficiently designed form of a hull? (seems to me that plain, flat bottomed "tubes" would be more efficient in the water than round bottoms)

2. The Water Glide only extends for about 10 ft under the deck...would a full length third pontoon be more efficient so far as speed is concerned?

3. Has any one out there ever added a plywood/epoxy third pontoon either partial length or full?

I'm not looking to build a speed pontoon boat, but a 5-10 mph or so gain would make a world of difference to my current setup without having to bolt on some monster outboard motor.

Thanks in advance for your time and knowledge.

[SamSam]

The site won't open for me, but to claim extra speed for a third pontoon seems suspect. I was under the impression they were for extra flotation only and would think a third one would slow the boat down through extra drag.

[Quietboats]

The web address has the ")" stuck in it mistakenly. Try this: http://www.pontoonwaterglide.com

[SamSam]

OK, thanks. The guy makes such big claims that some of it almost has to be true. Round tubes are not good at all for speed in a planing mode, and I think the shape of the product has a shallow v design, not round like the other two toons. It must help, but it might depend on how much hp you have to begin with.

[messabout]

Round pontoons are miserable ways to make a boat. They are efficient only at very slow speeds. Sure, there are those that go fast enough to pull a water skier, but they have enormous power to overcome the basic flaw in the design. Round pontoons are made that way because they are easy and relatively cheap to fabricate. Also the circular sections have better stiffness characteristics than rectangular shapes. Thus round ones need far less interior bracing than flat ones. In addition the boat type has evolved using round sections and have become the conventional way to build. In the process the round type has become mistakenly assumed to be the right way to do it.

[SamSam]

As for making a third toon, I don't know anyone who did it, but if that guys numbers are right, I'm tempted. Even just to get more flotation in the back end, I'm tempted.

[DMAN1968]

Thanks for the input.

Do you think that it would be better to just remove the present motor pod and build a transom and motor mount onto the new pontoon? Seems to me that if it were built more like a true boat transom (even though narrower) then it could help to solve some of a pontoon boats problems with prop ventilation.

Thanks again.

[ted655]

People tend to buy pontoon boats so they can rome around. Parents like them for the kids. Party dudes love em to. If you keep a boat in the water where it rains a bunch, they are not going to sink if the bilge pump fails. They are shallow draft & they also take side waves smoother. There is more room for sunbathing& you can dance on them.
.
They go downhill fast in performance & handling after the above advantages and just plain suck at many other comparisons of types of boats. I think it is a fear of water that drives their popularity. People "feel" safer on something that is NOT encapsulatd by water. They have never struggled to keep one upright that has 1 pontoon full of water.
.
I consider them to be a specialized type of craft with limited use. Any attempt to turn one into a multi use boat results in a costly, disappointing mistake. Get a boat with decks.
.
Make the 3rd. 'toon BIG, leave it oprn on the top, then you have a trimiran.

[SamSam]

I don't know how the product deals with the motor pod already in place. If what you have ventilates the prop, you don't have much to lose by replacing it. Whatever you make to replace it has to be able to handle the hp. That's one advantage to the present pod, it's designed for the hp. It might be easier to build "around" it. Ted's idea to make it big and leave it open won't really work under the boats deck. (But it does make one think of bolting a small jonboat underneath instead of the product asked about, or getting a junked boat for nothing, cutting off about 1' of the two sides, rejoining them together and affixing that to the pontoon boat like the product shown) Whatever is done, the thing will have to be enclosed to keep water out and/or to provide flotation.

[DMAN1968]

Okay, after doing some research between semi-displacement and planing hulls, I have a better understanding of the situation.

My question now is, if I wanted to add a third pontoon for added buoyancy, which would be best so as not to suffer any loss of the performance I already have? Would it be better to build my own with a flat bottom and square sides or buy an aluminum round tube for the center of my pontoon boat?

Thanks again

[Busman1965]

I did add a 3 pontoon to my 24 landau. It was a cheap ply/glass one, I made in about 2 days. It was only 10ft long, just enough to keep the bow up higher. It did not add anything to the speed, rather, it probably cost me a knot or so, but it really did improve the boat overall. My pontoon was a square shape, with a raked front end, and a flat stern. I added it, to overcome the extra weigh of a cabin i built on the deck. I worked well, and lasted over 10 years, for a couple of hundered bucks!!!

[SamSam]

Round will add flotation but also drag. Flat will add flotation, and going by the site you posted, if you can get it up to where it's planing, the speed might improve.

[DMAN1968]

Thanks for the info folks.

Busman, You don't happen to remember the width and depth of the one you made do you? And maybe where you mounted it on the barge...towards the front or middle? My problem is the stern sits considerably lower than the bow already.

Thanks again.

[MrRogers]

you may need to put lifting strikes on the sides for more lift.

[MrRogers]

I built a 33-foot pontoon boat with a 140 iron duke mercruiser and used 3 old aluminum 30'logs.I need to install lifting strikes on both sides of the logs and don’t want to weld. This will be about 25' long and made of 8-gauge aluminum bent to about 28 to 33 degrees. It will stick straight out about 4" to 5" from the side of the log. It will have two slightly beveled 2" flats on top & bottom. They will be for the epoxy can attach it to the log. Work will be done in a room at 50 to 60 degree. Boat will only be in fresh water but epoxy will be under water all the time when the boat is in the water. Hope you can help me?