Need some advice on launching and recovering my 2455

[Wingnutt]

Yea I?ve been doing it for over 20 years, BUT this is the first trailer that I?ve owned that floats! The trailer is a 2005 dual axle aluminum ?I? beam trailer. The interesting thing is that those four tires provide enough flotation to keep the trailer suspended in the water and create an undesirable angle to the boat. This makes for a royal pain in the cheeks to launch and recover the boat because...

When the winch and bow roller assembly (one piece welded together) are adjusted to the proper location, the bow pulpit hits the winch hard enough to put a bend in the pulpit until it clears the winch.

Lower the winch and bow roller assembly enough to place them below the bow eye and once the boat is on the trailer the bow eye is past the winch!

A happy medium means that I have to wade out waist deep or deeper and lift the bow of the boat so that the bow eye clears the roller on the winch and bow roller assembly, then proceed to launch or winch the boat into place.

Of course this will be quite a chilling experience for the boys once the water drops below sixty degrees. We usually go out until late October or early November depending on the weather, so I would really like to find a solution before then.

I?m not sure how much weight I would have to add to the trailer in order to keep it on the bottom, but I?m pretty sure that it would have quite a bit in order to offset the flotation provided by four 15? tires.

Anybody know how much weight a mounted 225/70/15 tire can float? Or how I would go about calculating the amount of weight that I would need to add?

Or ANY other possible solution?

 

[bruceb58]

Re: Need some advice on launching and recovering my 2455

Not sure what you are towing this with but equilizing bars may help. They would tend to want to force the rear of the trailer down.

 

[iop]

Re: Need some advice on launching and recovering my 2455

Tires floating trailers?? Wenched bending pulpits?? Way over my head... but you peaked my interest!!

 

[marcortez]

Re: Need some advice on launching and recovering my 2455

How about not putting the trailer in quite as deep.....then motor the boat up, where the hull will just touch those level/upright bunks.
Once it does, the hull will "push" down on the trailer, making it sink some.

Continue to motor up and back the trailer in at the same time......as the boat comes up more on the bunks, it continues to push down on the trailer.

Two man/woman operation for sure...and granted, a pain in the butt and would involve a learning curve to get it right.

Or another option would be to let out some of the air in the tires so they have less flotation.......sure you would have to experiment around with that and may not work at all.

Or...lash on some heavy railroad beams or I-beams, and play with those until you get neutral flotation.

Or enlist two of your biggest buddies to stand on the fenders and see if 500# of meat will help hold it down.

Final option would be to trade for a steel trailer....heavier.

A second look at the winch uprights...they appear to be adjustable.
Can you raise the winch stand and move the upright forward, to bring the roller more inline with the boweye?

 

[j_martin]

Re: Need some advice on launching and recovering my 2455

That's funny. The flotation is provided by the displaced water. How much air would you have to let out of a tire to make it significantly smaller?

Here's an idea. How about a strategically placed keel roller to bump the pulpit over the winch. Might have to be some sort of a rocker or spring loaded arrangement, but maybe not.

Load leveler spring bars sound like something worth trying. A little scrap metal bolted to the trailer is probably the easiest way to sink it. Maybe find a couple of zinc ingots from a metal recycler. That way you'd have sacrificial anodes at the same time.

 

[ondarvr]

Re: Need some advice on launching and recovering my 2455

How about not putting the trailer in quite as deep.....then motor the boat up, where the hull will just touch those level/upright bunks.
Once it does, the hull will "push" down on the trailer, making it sink some.

I like this, the most common reason for the bow and/or pulpit to hit the winch stand is from backing in too deep, but it can be complicated by the angle of the ramp.

At the right trailer depth the boat will ride up on the trailer and be positioned correctly to not hit.

 

[H20Rat]

Re: Need some advice on launching and recovering my 2455

Anybody know how much weight a mounted 225/70/15 tire can float? Or how I would go about calculating the amount of weight that I would need to add?

Easy! Each tire displaces 1.93 cubic feet. A cubic foot of water weights 62 pounds give or take, so each tire will float roughly 120 pounds, for a total of 480. (its the volume of a torus if anyone is interested...) Changing the pressure inside will have almost no affect. The tire won't change volume significantly until you get dangerously low, and on the other end, the more air you can put in it, the heavier it will be. (a tire at 20 psi weighs less than one at 100 psi, without doing the math it is probably around 1/3 of a pound or less difference in this case)

 

[iop]

Re: Need some advice on launching and recovering my 2455

Easy! Each tire displaces 1.93 cubic feet. A cubic foot of water weights 62 pounds give or take, so each tire will float roughly 120 pounds, for a total of 480. (its the volume of a torus if anyone is interested...) Changing the pressure inside will have almost no affect. The tire won't change volume significantly until you get dangerously low, and on the other end, the more air you can put in it, the heavier it will be. (a tire at 20 psi weighs less than one at 100 psi, without doing the math it is probably around 1/3 of a pound or less difference in this case)

So then the OP's trailer wheighs less than 500lbs???
I cant imagine tires floating a trailer... it seems impossible to me. Am I wrong or is this something that actually happens??

 

[Mr_Shamrock]

Re: Need some advice on launching and recovering my 2455

I had a similar situation with my previous boat - 22' Pro-Line. The way the factory set-up the trailer was way off. I fought it about 1/2 a dozen times until I wised up and went out after work one day when there was no one at the ramp, backed it in the water and just let it float back still attached to the winch strap. I adjusted the height of the winch and figured out exactly how deep I needed to back the trailer in. I was backing to far in to compensate for the misalignment and it was a wrestling match each time. After that it was smooth!

 

[Wingnutt]

Re: Need some advice on launching and recovering my 2455

Thanks for the ideas!

...the most common reason for the bow and/or pulpit to hit the winch stand is from backing in too deep, but it can be complicated by the angle of the ramp.

I would like not to have to back it in so far, but because the trailer is trying to float. The boat doesn't want to slide off the bunks until it literally floats off, so for now, back I have to go.

How about a strategically placed keel roller to bump the pulpit over the winch.

I really like the idea of a keel roller; especially since the bow is not as well supported as I would like. This is is compounding the problem because the bow drops down a good foot once the bow eye clears the bow roller. Also that's about how far I have to manually lift it in order to get it back over the bow roller.

...so each tire will float roughly 120 pounds, for a total of 480

It appears that I may not have to add as much weight to the trailer as I was thinking to keep it on the bottom. BTW, the trailer only weighs about 800lbs according to the literature that came with the boat when I bought it.

Looks like a couple of projects have been added to my to-do list. Thanks again!

 

[H20Rat]

Re: Need some advice on launching and recovering my 2455

So then the OP's trailer wheighs less than 500lbs???
I cant imagine tires floating a trailer... it seems impossible to me. Am I wrong or is this something that actually happens??

two things are happening that cause it to float (barely) The entire weight isn't on the tires, the truck supports some yet via the tongue, and second, the deeper you submerge the tires, the more flotation you get out of them.

If you were to unhook it and let it go, it would most likely sink to the bottom...

(the number I gave above doesn't count the tires weight, so you can subtract 20 pounds or so for each of the tires. aka you get roughly 400 pounds of flotation.)

 

[bruceb58]

Re: Need some advice on launching and recovering my 2455

and second, the deeper you submerge the tires, the more flotation you get out of them.

Its actually the opposite but won't matter here.

The guys that make these trailers probably have suggestions we haven't thought about. Have you tried calling them yet?

 

[smokeonthewater]

Re: Need some advice on launching and recovering my 2455

it seems pretty hard to swallow the idea that 400 lbs of flotation is floating a trailer that weighs 800 lbs..... that would mean 400 lbs of tongue weight from an empty trailer...... SOOOOOO let me suggest that the trailer isn't floating but rather you are simply backing in too far as suggested earlier... Most boats launch very nicely with the fenders on the trailer just protruding from the water but of course it varies by boat and ramp

I'd also say thhat the trailer "trying to float" would not in any way keep the boat from sliding off..... example: my wellcraft weight 10,000 lbs..... when in position to launch it probably still puts 3,000 lbs of weight on the trailer. If the boyancy of the trailer tires was 2000 lbs (of course it couldn't be) and the trailer weighed 1200 lbs then I'd have still have only 3000 lbs supported by the trailer and 2200 of that transmitted to the ramp below.

Next I'd say the reason you are backing in so far can easily be fixed with some keel rollers adjusted to take some weight off of the bunks. The boat should be able to be backed off the trailer with the engine at idle speed.

 

[H20Rat]

Re: Need some advice on launching and recovering my 2455

Its actually the opposite but won't matter here.

sure about that?

think of the tire as a fixed volume, for the depths we are talking here it is. A tire at 1 foot under the surface will absolutely have less bouyancy than one at 10 feet down.

It would be 100% impossible for objects to become neutrally bouyant otherwise. Lets say you are a scuba diver, and you trim your weights to make you neutrally buoyant at 10 feet. If it was true that your air tanks have less buoyancy at 20 feet, you would be in serious trouble! Once you dropped to 10.1 feet in depth, you would continue sinking, or if you were at 9.9 feet, you would rise. (hence, impossible to achieve neutral bouyancy) (in scuba diving you are technically changing your displacement, but without doing that, you could become neutrally bouyant at a specific depth with just weight and your air tanks)

 

[bruceb58]

Re: Need some advice on launching and recovering my 2455

sure about that?

think of the tire as a fixed volume, for the depths we are talking here it is. A tire at 1 foot under the surface will absolutely have less buoyancy than one at 10 feet down.

Very sure.

Been scuba diving for over 20 years. One of the first things they teach you is how your buoyancy decreases as you descend. Reason is the increased pressure reduces the volume of any air in your body or buoyancy compensator.

http://www-personal.umich.edu/~lpt/practical.htm
"As we descend, gas spaces in the diver and the diver's gear will, because of the increased pressure, decrease in volume with a corresponding decrease in upward buoyant force. So, as we descend, SMALL amounts of has are added to the B.C. to provide an upward force to compensate for this lost buoyancy."

 

[sheridon]

Re: Need some advice on launching and recovering my 2455

Is the Trailor frame filling with water as well or is it sealed. If its sealed the hollow frame is probably adding to the trailers floatation ability.

 

[ondarvr]

Re: Need some advice on launching and recovering my 2455

Is the Trailor frame filling with water as well or is it sealed. If its sealed the hollow frame is probably adding to the trailers floatation ability.

The trailer isn't made from hollow tubing.