Sailboat Trailer

[capncook]

I recently purchased a Helms 25 and it didn't come with a trailer. I then found an individual on Craigslist that sold me a trailer for $400 but it came up a little short, almost eight feet. he included a 20' piece of box tube that matches the existing so I could replace and lengthen the tongue section, but on that particular boat (or any with a swing keel) I'm not sure how much stern is "safe" to hang off.
Any suggestions?

[Maverick1958]

Had a simular problem with my Helsen 22. It came with a trailer, but it was rotten. I made a new one from scratch and it turned out rather well. Stern overhang is not the real issue as long as there is adequate support for the keel and hull. My boat overhangs the back of the trailer about 5 feet, but the keel sits completely on the trailer with an additional 6-8 inches to spare. Tounge weight is the primary concern as long as the boat is properly supported. There are as many opinions as to the proper amount of tounge weight as there are members on this board. Mine is a bit on the heavy side at 150lbs. Personally I would recomend 100lbs for the tounge. Too much weight in the rear will make the trailer weave, sometimes uncontrollably. There are a couple of more thing to consider. Who is doing the welding and how do they/you intend to weld the additional length to the tounge. It needs to be a full penetration weld. Just as important is torque arm ie. bending moment you will be putting on the tounge. A perfect weld will not help if the thing collapses due to too long of a tounge. Just a few thoughts

Maverick PE

[capncook]

Thanks, I appreciate all the info. I won't be able to tell much until I try to put it on the trailer and test fit the boat to the trailer. With the preliminary measurements, the boat will hang off about 8', seems too much to me.

[merc2dogs]

A large chunk of the trailer behind the axle isn't actually needed to support the boat.
Once the center of balance is known, all you need is roughly halfway to the stern past it for support, anything past that is wasted trailer as far as support goes.
But.....
I think the lighting requirement calls for lights to be within four feet of the end of the load, so you may as well build the trailer out that far

If the CG of the boat can be placed slightly forward of the axle while leaving enough room for the tow vehicle, and the trailer extends back far enough to support the boat,Then all you need is a light framework to support the lights

Ken.

[NCC320]

If you plan to tow your boat with this trailer on the highways, there is another set of concerns that haven't been mentioned. What losd is the trailer rated for? Are the springs rated for the load (your boat's weight plus trailer + gear..motor, gas, etc.), are the tires rated for this load, how about bearings (condition/size), and how about the axle? If any of these components go at highway speed, you're in deep trouble.

Also, as you add your extension, you have to maintain proper balance. The boat should sit on the trailer such that the tongue/hitch carries ~10% of the trailer load according to what I have read. This may mean that you have to reposition the wheel assembly or reposition the bunks.

A long extension added to the tonque needs to be heavy/strong enough that the trailer/boat is not flexing up and down when you travel (essentially this is part of your original question), but it can't be answered without knowing details the trailer tubing (dimensions, wall thickness, material, etc.) and doing some calculations that most of us don't know how to do. Anyway, the point here is that you don't want your boat flexing up and down with the trailer on the road.

You might be better off getting some measurements on the boat and buying a trailer that is already suited for the task. If you try to make do with a grossly undersized trailer, you may well have lots and lots of expensive problems. You can always resell the too small trailer to recover your cost in that item.

As for trailer overhang beyond the bunk supports, a little bit is good since this will facilitate the yard lifting off the boat for bottom painting. But beware of making the bunks too short allowing to much unsupported area in both directions. Short bunks will tend to cause the boat to rock and flex more, thus putting stresses on the hull that it shouldn't experience.

[cruisingdream]

tounge weight for a standard trailer (travel trailer) should be 10%
for a boat trailer you can go as low as 5% this has to do with the location of the center of gravity & length from the hitch to the wheels. so if the boat & trailer combo weigh 3000 lbs tounge weight should be at least 150 lbs. a little heavy is better than too light.