Tapered Pontoon stern

[RadioDave]

Regards to Scott Danforth, what he says makes sense.
how I got in plane with 500 pounds of gear and people was what I read, o tilted all the way forward, and acheved all the speed she would do, then pitched back.
she lifted several inches up in the nose, and went faster.
just two tubes in the water.
it planes out that way.
however not like a v hull boat.
what I did notice is that the waterline in the tunnels is much higher than outside the boat, shooting out like a overloaded spillway.

 

[RadioDave]

The bottom of the transom is the waterline parked.
the prow waves sum together, and load up on the bottom of the floor.
seems, if one carried the transom geometry to the toons, that wave would push up on the additional hull, and cause displacement.
the "hull" could be open in the back, and would be above the static waterline.
However at speed should cause a planing effect, as it would be a planing hull.
At 62 pounds a cubic foot, just 5 cubic feet a side may do plenty.
Is that a crazy idea, ir does it hold water?
Or better to say, doesnt?

 

[ahicks]

Maybe I've been around 'toons too long (first was '78) so I guess I think of them as they are.

Some do "skin" the bottom of thier floors with aluminum to minimize the drag from water splashed up onto the cross members, but again, I would question the merit of that move for a boat not likely to ever see 20mph.

I'd agree on how long the motor will last. Just put a pump impeller in it every 2-3 years, need it or not, and keep the carb clean. Engine's enemy is heat. That destroys gaskets, and kills engines.

 

[RadioDave]

I meant a jonboat hull of sorts, purtruding down 18 inches.
above the waterline but under underway.
for the purpose of lift in the tunnel, there is quite a bit of water rise.
make a planing hull astern.
I'm a newbe, expect a laugh about now.

 

[RadioDave]

Oh, I try to use methanol free oil as much as possible, with StaBil, Mercury Silver, and occasional Sea Foam or Marvel Mystery oil.
The Multigauge I bought has water temp and pressure built in.
8 haven't installed it yet

 

[jetboater]

RadioDave——congratulation on your find! Sounds like a great deal!

you mentioned the tires look “factory new”—-may want to check the date code on them and see how old they actually are—-most tire manufacturers recommend replacing them when they’re 7-10 years old. If yours are the original ones, they’re 22 years old.

I replace mine about every 9-10 years—-I don't want to be dealing with a flat when I’d rather be enjoying a day on the water.

Heres how to check the date on tires made both before and after the year 2000—

https://www.tirebuyer.com/education/...-of-your-tires

 

[garbageguy]

I'm guessing tapered toons are not really a thing for several reasons, even though they might provide a more efficient planing "hull". Those reasons might include; cost to produce, stability at rest and bow/stern relative bouyancy, acceptability of additional cost to target customers, relative objective of this type of boat

 

[RadioDave]

Right on Jetboater.
and they are those short fat ones too, glad the dock is 20 minutes away.
they can rot from the inside out.
first thing I changed out, kept the spare though.

Garbageguy, I have put much thought to the tapered thing, I'm betting they buy round tube in tree-lined sections, cut and cap.
that would make the taper the most labor intensive part.
cost must be why.

 

[RadioDave]

[No message]

 

[RadioDave]

Coming soon, twin 45 pound reversable thrustors!

 

[NYBo]

My condolences on the loss of your wife.

I can get 18 MPH measured by GPS from the pontoon boat in my signature. You should be able to something similar. What prop do you have?

 

[RadioDave]

I'll find out the diameter and pitch.
I can hit 5000 rpm within seconds from a standing start.
thinking more pitch.

will be adding two trolling batteries.
was thinking front to help distribute weight.
should I re consider the rear? Logs are deep in the rear.

 

[RadioDave]

We are adding two deep cycle batteries.
are these better stored up front, or in the rear?

 

[ahicks]

Put them up front if you can do that and keep them out of the way.

 

[wahlejim]

Tapered logs were common on Pontoons in the late 80s/Early 90s. Riviera Cruiser and Sweetwater used them. I have a 91 Riviera Cruiser, 25 feet long. At best, it adds a little buoyancy to the stern. Doesn't do much for speed or wake. Minimal changes at best when I run alongside my neighbor.

 

[RadioDave]

Well, that truly answers my question.
I'll work on weight and pitch

 

[RadioDave]

Prop appears to be 12.5 8 pitch.
can they slip on their rubber mount?
I can hit 5000 rpm within seconds of wot from a standing start.

 

[RadioDave]

Correction 10 8p

 

[RadioDave]

I am being recommended a 12x9, could that be too much?

 

[ahicks]

Usually when a hub starts slipping it's like the engine has been shifted into neutral. It'll start out OK, but then when it gets enough load on it, it' gives up the ghost.

Going from a 10x8 to a 12x9 is pretty much guaranteed too much. You're sure about the 10x8, or is that a guess? I ask as that seems pretty small in my experience.

To have a basis to suggest anything, need to know your target rpm. What rpm do you want the engine to turn?