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V10man
10-15-2003, 01:40 PM
I am so glad I found this site.. :D I've been lurking for a while now, reading all the posts. Fantastic information!!! :D I hope you experts can help a newbe.

I'm thining about building a 6'x14' single axle trailer to haul 2 ATV's. I'm guessing it will weigh 3000-3500 pounds. Maybe a bit more. The trailers I have looked at around town use 2x3 angle for the frame and sides. I would like to use either 2x3, 2x4 tubing or 4" channel because I want a solid frame then I'll enclose it. I can buy the 2x3 or 2x4 tubing in .188 thickness or the 2x4 in .250. I don't know what the channel is. Is .188 thick enough or should I go to .250? Is channel better? Is 4" wide enough or should I go 5"? I'm planning on using a 5200lb axle/springs w/brakes. I don't think I'll ever weigh it down that much but it wouldn't hurt to be able to. I don't want to go with tandem axles.

I was going to build the walls out of .065 1" square tubing, 16" OC, the roof and rear opening out of .065 1x2. The roof also 16"OC. I was going to skin the sides with aluminum RV siding, and the roof with 3/8 plywood and either aluminum or rubber. Basicly it will look like a travel trailer. The rear doors (not a drop ramp) would also be 1" tubing.

Thanks a bunch fellas! Believe me, I have lots more questions.

Dirt Rider
10-15-2003, 02:58 PM
Not to direct you away from this awesome forum, but over at www.aws.org go to the forums and search "trailer". Look for some posts from a guy named Goose. He built a **** of a nice trailer for his race car and used 2x4 tubing for the main frame sections. He also had some heat warping issues when attaching the floor plates, etc. Anyway, it's some good reading and will certainly offer some ideas and helpful hints. There was a link to some photos there too.

Scott

AV8OR
10-16-2003, 12:46 PM
A book you might want on your bookshelf at home would be "Trailers: How to Design and Build, Volume 1" by M.M. Smith. Amazon.com (http://www.amazon.com) carries his books.

http://www.ssapubl.com/pictures/102.jpg

bitternut
10-16-2003, 10:14 PM
V10man ......I purchased plans for a 16' tandem axle 7000# car hauler trailer. The main frame plan calls for 2x4x1/8 rectangular tube for the side rails. The cross rails are 2x3x3/16 rectangular tube on 16" centers. The tongue is 2x5x3/16 rectangular tube. This is a tandem axle trailer not a single like you are considering but this might give you an idea of what would be appropriate for the trailer you are building. I would assume that these sizes would easily carry your load.

That book that Av8or suggested might be a good idea. I will have to check that out myself.

axehind
10-16-2003, 11:45 PM
Also know that each state has different requirments. Here in MA any trailer you register that is made to carry over 3000lbs (I think)has to have its own brake.

axehind

big tuck
10-21-2003, 12:14 AM
i am in the process of building a 12x6 trailer and the plans call for 3x4 .25 northern tool plans

V10man
10-22-2003, 11:32 AM
Thank you everyone! I think I am going to use the 2x4x3/16 tubing for the side rails, front and back rails and the tongue. I'll use 2x3 angle for the cross braces on 24" centers. I was thinking of adding a 2x2 angle down the center. That would give the floor 2'x3' sections. (instead of 2'x6' sections) Good enough for 3/4" T&G plywood? Also, I was wondering if I welding the spring hangers to the 3/16 tubing is OK. I could use some scrap 2x3 angle and weld that to the tubing then the spring hangers to that. I'm thinking that would give the spring hangers a thicker base and also spread the load a little. Am I being overly cautious? Thanks again! :cool:

Dirt Rider
10-22-2003, 12:46 PM
If you have a digital camera, be sure you keep it handy and send us some pics! :)

Franz
10-22-2003, 12:59 PM
I've been pondering this thread, and unless your ATVs are tracked vehicles, how are you figuring the total weight will be 3000#?
Yes, you can weld the spring hangers to the tube frame, BUT, you'll wind up with a nicer ttrailer if you set it up with an adjustable axel, so you can slide it when hauling different weights.
Since you're in Az, rust shouldn't be a problem.
Rather than running an angle down the center, you'll be much better off if you put the cross members on 12" centers. T&g plywood isn't going to make any difference on a trailer deck, other than making it more difficult to replace a single sheet. I use pressure treated plywood, and replace as necessary.
You can also truss your siderails and gain a lot of deck strength, as well as gain attachment points for your load. If you look at a rolloff wrecker deck, you'll see that a lot of the deck strength is in the siderails.

Sberry
10-22-2003, 01:18 PM
I tend to agree with the Old Timer here about narrowing the spacing and skipping the center angle. The deck boards will provide that stiffness. I think the trailer book is an excellent idea, home built trailers tend to be too heavy to make up for some poor structural engineering. You should see the first monster I ever built,,, ha, way overkill and way too heavy. I think I would opt for lighter tandam axels too,,, they handle much better than singles. I add rolled black plastic pipe in the design for wiring too.

Bobby
10-22-2003, 03:34 PM
Check out http://www.championtrailers.com/UTILITY_TRAILER_KITS.HTM they have all kinds of trailer parts plus have some rough diagrams for the design of said trailer kits.

trackwelder
10-22-2003, 07:09 PM
I have two of that authors trailer books,and they are a great resource.I ordered them from northern tool a few years ago and they where about twenty bucks each.

Bender
10-22-2003, 09:07 PM
I think I've decided to put plywood on my trailer and am wondering. How thin can I go? My cross members are on 24" centers with no supports. I'll be carrying no more than a go-cart or riding mower. At least that's the plan. Thanks.

Yeah, V10man. Where's the pics. hehehe

bitternut
10-22-2003, 09:37 PM
I have noticed that trailers of the same size and load capacity are made from different shapes of structural steel. Some are angle, rectangular tubing or channel. I have searched for the benefits of one shape over another and have come up with nothing.

For example which shape of material would yield a stronger trailer frame, 2" x 3" x 1/4" angle or 2" x 3" x 1/8" rectangular tubing? The angle iron weighs a little more at 4.133# per foot compared to 3.904# per foot for the tubing. I have also noticed quite a few trailers use channel for the tongue. Anyone know of a chart that shows the relative strengths of the various shapes? I know such a chart would be a lot of help to V10man and others building their own trailer.

V10man
10-23-2003, 06:13 AM
Good thinking on the T&G plywood. Forget that. My buddys atv trailer is made out of 2x3 angle with a top rail made from the 2x3 angle too. Just like the champion trailer web site plans(I ordered their catalog a while back) This truss style is very strong. I want an enclosed trailer so I think a tube frame would be better. I want a single axle because to store the trailer I need to push it 90 degrees from my yard to the side of my house. Very difficult to do with tandem axles. I guessed at a 3000lbs total weight. I figure 1200lbs for the 2 quads. My rough calculations tell me just for the frame, crossmembers and tongue I'm at 638lbs. Still need to add the hitch, jack, fenders, springs, axle, wheels and tires, lights, chains etc. Also the enclosure. Wall and roof framing, aluminum siding, insulation, paneling, maybe a couple windows, back doors, 2 ramps, 12v battery, stablizing jacks, roof vent, maybe even a 12' awning on one side and fold down bed bunks. :D If I could do all this and be under 3500lbs total that would be great! The 3500lbs axle and related parts sure are cheaper.:D

Bobby
10-23-2003, 09:06 AM
Originally posted by bitternut
I have noticed that trailers of the same size and load capacity are made from different shapes of structural steel. Some are angle, rectangular tubing or channel. I have searched for the benefits of one shape over another and have come up with nothing.

For example which shape of material would yield a stronger trailer frame, 2" x 3" x 1/4" angle or 2" x 3" x 1/8" rectangular tubing? The angle iron weighs a little more at 4.133# per foot compared to 3.904# per foot for the tubing. I have also noticed quite a few trailers use channel for the tongue. Anyone know of a chart that shows the relative strengths of the various shapes? I know such a chart would be a lot of help to V10man and others building their own trailer.


It has to do more with the strength properties of each section in the direction that the force will be applied. Some sections provide the use of less poundage of steel for the strength needed. like youre example above. For the Angle to provide the same strength it might require a thicker flange than tubing. If you're buying by the pound then the tubing might be a better option if it provides the same structural capacities. Basically it requires a good bit of calculations. or do like many do and WAY over engineer something so that it ways WAY more than it needs to.