How far can a boat hang off of a trailer?

[MushCreek]

I'm looking around for a used trailer for the Peregrine 18 rowboat I'm building. Although it's 18' long, it's very light, and the center of gravity is roughly in the middle, rather than at the transom like a power boat. Also, an 18' boat trailer would be way overkill and too stiffly sprung. All of that being said- is there a practical or legal limit that a boat can stick out past the back of the trailer? If I buy a trailer from say a 12' jon boat, is that 5 or 6 feet sticking out going to be a problem?

[hawkeye54]

MC, I am still not familiar with SC DMV requirements, but, like lumber overhanging a truck tailgate, it would be best to have a flag or lightboard at the transom of the boat. Lots of examples of lightboards, mounted to rudder hardware are on this forum. Also, see if you can move the winch stand forward as much as possible on the trailer. Hope that helps,


Rick

[Arlc]

I think where the center of gravity of the boat is and the stress on the hull/frame when going down the highway are additional issues to consider. Need to keep. some weight on the hitch end also.
Re used trailers, my experience has been most used lightweight trailers are for sale for a reason. You can buy a new one for about the price of the used and repairs.

[Jim Ledger]

So long as the rated capacity of the trailer exceeds the boats weight I think that the main factor to consider would be the tongue weight of the trailer. Too much boat hanging off the end will result in a too-light tongue. Moving the winch pylon forward will both increase tongue weight and reduce the overhang. It's a balancing act. The more boat hanging over, the easier it will be to launch.

Jim

[WI-Tom]

I'm far from an expert, but I don't know that I'd be comfortable with 5-6' of boat hanging off the back of a trailer, even for a light boat. Seems like a possible place to crack and/or start hinging open to break the keel. But what do I know?

My own 18' row/sail boat weighs about 250 lbs empty, I think. Trailers for long light boats don't seem to exist. I went with a WAY over-strong trailer that's 18' long from hitch to end. With the hitch post moved as far forward as I can get it, the boat hangs off the end by about 2 feet. The rest of the keel (flat, no rocker) is fully supported on a wide plank. After 5 years and a whole lot of highway miles, it's holding up fine.

Tom

[Yeadon]

You can build a flatbed out of pressure treated lumber that hangs a few feet off the back of a trailer. That will add some support. Also, many states have laws on the maximum distance between tail/brake lights and the back of the load that you're towing.

[rgthom]

My 250-300 lb, 18 foot rowboat hangs 44 inches off the back. Most weight is on the center bunks, but it has a long skeg and the end roller supports the skeg. There's a light bar on the transom. 12 years and many trips so far no issues.

-Rick

[dbp1]

I'm far from an expert, but I don't know that I'd be comfortable with 5-6' of boat hanging off the back of a trailer, even for a light boat. Seems like a possible place to crack and/or start hinging open to break the keel. But what do I know?

My own 18' row/sail boat weighs about 250 lbs empty, I think. Trailers for long light boats don't seem to exist. I went with a WAY over-strong trailer that's 18' long from hitch to end. With the hitch post moved as far forward as I can get it, the boat hangs off the end by about 2 feet. The rest of the keel (flat, no rocker) is fully supported on a wide plank. After 5 years and a whole lot of highway miles, it's holding up fine.

Tom

Not quite true that they don't exist.

e.g., this is 18.5', says it is for boats up to 22', and sprung only for up to 350lbs.

https://www.trailex.com/products/pc/...-350-S-p27.htm

(I own a different one of their trailers, and the adjustments are nice -- you can move the box that holds the axle, adjusting where the weight is supported, as well as the supports for the boat itself).

They aren't cheap, but they'll ship them anywhere in a couple boxes and after several hours of assembly, you'll have a trailer.

To the legal question -- I'm sure it varies state to state. I think here, the overhang can be something like 4', but you can go beyond that with a flag tied on, and that 4' may be from the lights, rather than structural parts of the trailer (I don't remember exactly, because the rules were beyond what I was ever going to do!).

[P.I. Stazzer-Newt]

That's a twenty foot sailboat

FF_Trailer.jpg

[John Meachen]

Over here we would look on this Osprey on it's trailer as nothing out of the ordinary,LOA is 17'6".



Lights typically are mounted on a board that picks up the transom gudgeon and pintle.

[stromborg]

My 250-300 lb, 18 foot rowboat hangs 44 inches off the back. Most weight is on the center bunks, but it has a long skeg and the end roller supports the skeg. There's a light bar on the transom. 12 years and many trips so far no issues.

-Rick

A light glued-ply boat like the Peregrine 18 ought to be fine on a trailer like that. Poking around looking for trailers I get the sense that most of the "off the shelf" types are built to support motorboats over their full length to accommodate the heavy engines they tend to have hanging off the transom. "Traditional" wood boats need/want more support because of the way they are built. Bouncing down the highway at 70 mph is a bit different than bashing through chop at 3 knots.

I have found the longer a trailer is between hitch and axle the easier it is the do things like back down the drive and/or ramp. But that increases your turning radius and tongue weight so it is a balancing act. If you start getting more than 4 feet or so between lights and end of boat you might consider hanging a light bar off the back end, this will keep you from having corrosion problems in the lighting system too.

[swoody126]

in Texas it isn't BEHIND THE TRAILER

it is BEHIND THE LIGHTS

by LIGHTS they mean a full set that duplicates the running turn and brake lights on the tow vehicle

that limit here is 48"/4'

there is no restriction on placing a light board on your transom which would have your LIGHTS behind the transom

sw

[Canoeyawl]

in Texas it isn't BEHIND THE TRAILER

it is BEHIND THE LIGHTS

by LIGHTS they mean a full set that duplicates the running turn and brake lights on the tow vehicle

that limit here is 48"/4'

there is no restriction on placing a light board on your transom which would have your LIGHTS behind the transom

sw

When is the last time anyone measured your overhang? A foot of so no one is ever going to check.

As long as the beam strength of the hull is up to the cantilever, and you have tongue weight there are few rules.
Many states will allow a red flag (during daylight) on overhangs past 4 ft.
After sunset a single red lamp at the extreme rear is usually permissible as long as the turn and brake signals are visible, and on a trailer they usually are well under the boat and visible.
I have never measured but I'm certain my boat/mast etc is 6-8 ft behind the end of the trailer.

[JimConlin]

You might be able to order the trailer with a longer tongue. Ask your dealer.

[The Jeff]

I've got a 15' stitch and glue dinghy that sticks over about 3'. I built a better trailer setup for it a few years ago with a central platform that helps support the keel. The side bunks really just keep the boat from tipping and aid loading.

I have found the longer a trailer is between hitch and axle the easier it is the do things like back down the drive and/or ramp. But that increases your turning radius and tongue weight so it is a balancing act.

It's the ratio between vehicle's wheelbase and the hitch to trailer axle distance. Backing my trailer with my compact car is simple but it can get away from me with an F-250. This was the easiest trailer I've ever backed, although it did take 40 acres to get turned around:

[MushCreek]

Lots of good ideas; thanks! I was planning on adding some sort of support for the keel, such as what The Jeff posted. I also like the idea of hanging a light bar off of the transom. I don't trust other drivers to pay any attention to the BOAT that they are about to hit. The Trailex trailers are nice; my brother got one for his Gannet. I may eventually build one, but time and budget are tight for the time being. The Trailex is built from 80/20 aluminum extrusions, simply bolted together. The spring mounts are steel, bolted to the aluminum frame. I have a machine shop, so metal fabrication is much easier for me than boat building. For the short term, though, used small boat trailers are readily available around here for $200-300. I've rebuilt enough trailers over the years to know what to look for, and what the parts cost.

[AJBTC]

When is the last time anyone measured your overhang? A foot of so no one is ever going to check.

No one will check until you get rear-ended and the driver that ran into you claims a whiplash closed head injury. In most states the driver that rear ends is at fault. But if they could prove that your boat overhung too far you might be facing some liability. It would be on my deposition question checklist, for sure.

[amish rob]

Just remember when you add a light bar that you can’t ground to the trailer…

[P.I. Stazzer-Newt]

Over here we would look on this Osprey on it's trailer as nothing out of the ordinary,LOA is 17'6".



Lights typically are mounted on a board that picks up the transom gudgeon and pintle.

Tell me that the Messerschmitt has the tow hitch.

[Canoeyawl]

No one will check until you get rear-ended and the driver that ran into you claims a whiplash closed head injury. In most states the driver that rear ends is at fault. But if they could prove that your boat overhung too far you might be facing some liability. It would be on my deposition question checklist, for sure.

Which is why you tie a red flag or add a light to the overhang, or both!
I have hauled steel beams and log loads that extended 20 feet beyond the trailer.

[Hwyl]

Edit….I was wrong.

[Bruce Bateau]

Hanging off is cool:


Hanging out with friends:

[Bill Perkins]

[/QUOTE]

[AJBTC]

Which is why you tie a red flag or add a light to the overhang, or both!
I have hauled steel beams and log loads that extended 20 feet beyond the trailer.

Correct--the flag or lights should be okay. I thought the question was how long you can hang it past the lights.

[Nicholas Scheuer]

Peter Duff at Edey & Duff thoug 4' was the limit, which is why he euipped all Dovekie's with a light and license bar secured to the aft deck. Dovekie's special trailer terminated well ahead of the stern so that one could "tip" the hull off the trailer when launching in hope of keeping the wheel bearings dry.

[rgthom]

Peter Duff at Edey & Duff thoug 4' was the limit, which is why he euipped all Dovekie's with a light and license bar secured to the aft deck. Dovekie's special trailer terminated well ahead of the stern so that one could "tip" the hull off the trailer when launching in hope of keeping the wheel bearings dry.

That's how I do it, works unless there's a lot of waves.

[Canoeyawl]

Boats are nothing special, overhangs are permitted until you exceed the maximum vehicle length without a permit. California is 75 feet. The safety gear, flags lights etc are a separate issue. I have towed long overhanging stuff (Poles/I-beams just clamped onto a single axle using a bull ring attached to the end) and using a strobe just to keep people from getting involved in the "cheat" of the load sweeping across an intersection.
In the case of a boat, especially a small boat, it is much more about the strength of the hull.

Here's a permitted 129 foot load with a '34 foot overhang!
I sure among other things this requires a pilot vehicle or two
3572502F-9DDB-4D86-9D7E-EEE4CD710DE1.jpeg

[dt123]

Just remember when you add a light bar that you can’t ground to the trailer…

Wait. What? Why not? (I am about to make a light bar.)

[The Q]

UK , it's beyond the lights,
1M no Problem,,
1 M to 2 M you Need a Flag on the back,
2-3M you need a warning triangle illuminated at night.

over 3M you need an escort vehicle.
My boat is exactly at the 2M limit, so I've made a warning triangle

[MushCreek]

I don't see why you couldn't ground a light bar to the trailer. You'd just have to make sure to run a ground wire to the trailer frame. I had a fiberglass dune buggy many years ago, and every electrical fixture had to have a ground wire to the chassis.

[Canoeyawl]

Easier to just make up your lightbar with a long cord that plugs into the tow vehicle w the ground included
Forget about lights on the trailer.
(We have a magnetic set-up for long loads with a 50 foot cable but it wont work on wood! (every towtruck on the planet has this)
(I used C-clamps with some heavy leather chafing gear to hold it on the transom)

[stromborg]

Easier to just make up your lightbar with a long cord that plugs into the tow vehicle w the ground included
Forget about lights on the trailer.
(We have a magnetic set-up for long loads with a 50 foot cable but it wont work on wood! (every towtruck on the planet has this)
(I used C-clamps with some heavy leather chafing gear to hold it on the transom)

What Canoeyawl said x2

[Nicholas Carey]

So long as the rated capacity of the trailer exceeds the boats weight I think that the main factor to consider would be the tongue weight of the trailer. Too much boat hanging off the end will result in a too-light tongue. Moving the winch pylon forward will both increase tongue weight and reduce the overhang. It's a balancing act. The more boat hanging over, the easier it will be to launch.

Jim

Getting tongue weight and load distribution right is kind of important.

https://www.youtube.com/watch?v=w9Dgxe584Ss



Mechanical engineering professor at the University of Bath in the UK.

https://www.youtube.com/watch?v=zwlgZG55QWk