Tongue design question

Been thinking of building a small dual axle trailer. I have available to be 4x4 inch steel tubing at scrap price.
Anyway, been thinking about simplicity vs strength in terms of tongue
design.
I like the idea of using a straight tongue that goes through the front of the trailer support then has A frame sides that attach (weld) to the front trailer support. This seems like a strong design. However, it seems to me it would take me longer and require a fair amount of precision. (have to cut the ends of the A frame at an angle to meet the front support, having to cut the front trailer support in two pieces to meet the center tongue. Then afraid I would not have everything square in terms of the distance from one side of the tongue tip to the frame as compared to the other side.
Most trailer designs seem easier, basically, making a square for the trailer frame. Then fabricating an A frame tongue and placing it on the upside down trailer frame, measure to ensure the tongue is square with the frame and welding it directly underneath the frame.
However, it seems those welds will be taking all the force and a person better have extremely good welds. (Which I am practicing but that worries me).
Anyway, was wondering what your thought were. I was thinking a 6 feetx12feet dual axle.
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One other thing I forgot to mention, with the "through" design would the tongue be too short to cause the trailer to "ride too high" in the front end?
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One way to control this is to use a bigger offset "drop" ball-mount in the truck hitch, so that the final ball height fits the trailer tongue height better. Another is to build a structure on the front of the trailer that allows you to mount the coupler higher up (though this will again need reasonably strong welds). Last but not least, there are adjustable coupler mounts available, which allow you to move the coupler up or down as needed.
Look at the channel mount pieces here, for example: http://www.championtrailers.com/COUPLERS.htm and then keep poking around their site, they've got a lot of parts and usefull information.
--Glenn Lyford
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What do you think of the "through" design vs "bottom" design?
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If you have to ask, I'm worried. For a novice, go with the 'bottom' design as it involves less cutting, and securely bolt & then weld. Only when you can weld.
Phil.
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Use a bottom design for the tongue. Otherwise you'll be making a lot of little pieces for your bed.
For the A pieces, don't fabricate from two pieces. Cut a notch where the bend is leaving one outside wall that you will bend to the 50 degree bend. You won't have to heat it to bend it. It is easy to bend. Then weld at the point where the notches meet. This way you won't be relying totally on the weld. As stated previously, bolting would be a good idea. Also a shear plate welded from the A piece to the trailer bed at the sides will help reduce the tension stress of the weld between the A piece and the bed under the bed. This will place that weld into shear rather than pure tension.
You should organize the pieces to that the welds are into shear rather than tension as much as possible, particularily if you are new to welding. Don't forget, you are liable for anything that fall off your trailer on the highway.
Also, you should be studying trailer plans that are on the web and looking at examples locally at trailer sales places.
Plan out the whole trailer first. You should know exactly what piece goes where before you even start.
Start building the trailer upside down first, do all the welds and then flip it. You don't want to be flipping a trailer this size continuously.
4x4 inch steel tubing may be somewhat large for this type of trailer.
Steve L.
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Thanks. The tubing is not what I thought but I bout it anyway. It is 3x3 1/4 inch tubing. I only have 4 10 foot pieces. It only cost me 10 bucks though.
Been thinking, maybe I should just make a single axle 10 foot trailer as a project.
Been thinking first of making a boom pole for my 8n, maybe using that to lift the trailer frame.
Anyhow, what do you guys think? I am sorry for all the questions but I am learnign alot.
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Good deal.

I think you'll find a single axle 10' trailer to be amazingly useful, even if it won't haul your 8N around. Especially if you use one of the mid- to higher-load rating axles on it, and put tires on it rated for the axle load. Since lower trailers are more stable and easier to load, consider using a drop axle. I'd seriously consider adding electric brakes, too.
With all that, though, there is a tradeoff between trailer weight and capacity. I find that I never use my homemade 1100 lb. (empty) utility trailer anymore, even though it will haul 1900 lbs. It's just too heavy for everyday use. But I use the little 4x8 import trailer I have a lot, because it only weighs about 400 lbs. empty and is a lot less stressful to tow, for me and the vehicle (but then, I have a smaller truck than you, too). The little 4x8's are cheap from places like Harbor Freight, even the ones with the nice 12" wheels. You might want to start with buying or borrowing one to see if it will do a lot of what you want to do--you might never move up, or you could learn enough about how you actually use a trailer to change your mind substantially about what you need--I did.

I think that's an excellent idea.
Hope that helps, --Glenn Lyford
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What do you mean by the shear plate? I am having trouble understanding where it goes.
I thought about drilling and tabing the tongue a pieces and the frame where I could thread a bolt from the top part of the tongue tubing into the bototm part of the frame, then also welding it. Would this be a good idea?
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