I am going to build a 14' trailer to carry my jeep on 7000# would 4" square tubing be a good way to go I was thinking about using 3/16" thick 4"x2" tubing. The deck will be metal deck if that were to affect any thing.

4" square tubing or 2"x4" rectangular tubing: Which is it?

If you don't know the difference, you ought not be building a trailer.

Rectangular tube would be the better way to go - square tube ends up being overweight for the structural properties for something like what you are doing.

4" square tubing or 2"x4" rectangular tubing: Which is it?

If you don't know the difference, you ought not be building a trailer.

Yea rectangle tubing 4"x 2" x 3/16" I have always called it square. As for my building ability I will post up some progress picks as soon as I get started to make sure it meets you high standard. Now as for the rectangle tubing would that be strong enough to get the job done.

Sounds heavy to me.

For a 14' long trailer, it actually seems a bit light to me.

Well, I'm basing that off the fact that my 16 footer is made primarily of 3" C-channel. It does flex a bit, but I think you'd be better off with 4 or 5" C-channel than 2x4 box. It's just adding weight where I don't think you need it, but I'm no engineer.

Depending on your design and your fab abilities, 4x2x0.188 wall should be fine for a 7000# trailer. The trailer may easily approach 2000# although about 400# of that would be unsprung weight. So 7000 - 1600 = 5400 load capacity. If you factor in the tongue weight at 10%, you would technically have 5840# of load carrying capacity. Should be fine for a jeep. Of course those are just WAG numbers pulled out of thin air, but gives you an idea.

No disrespect, but I seem to recall seeing your trailer thread and the general consensus seemed to be that it needed more beef.

That said, c-channel would likely be the way to go.

my last trailer was 18' made with 4" x 3" x 1/4" angle it was a little on the week side you could stand on one corner and the other corner would lift and I dont want that this time however I think for such a short trailer 5" C channel would look to big that is the reason I like the idea of 4" tubing.

For a 14' long trailer, it actually seems a bit light to me.

Well, I'm basing that off the fact that my 16 footer is made primarily of 3" C-channel. It does flex a bit, but I think you'd be better off with 4 or 5" C-channel than 2x4 box. It's just adding weight where I don't think you need it, but I'm no engineer.

4x2x0.188 I=3.66
4x2x0.250 I=4.49

4 x 5.4# channel I=3.8
5 x 6.7# channel I=7.4

Basically, the higher the I value, the stronger the beam is in bending. However, rectangular tube is torsionally stiffer than channel. So again, it depends on the intended use and the design.

4x2x0.188 I=3.66 wt. = 6.86
4x2x0.250 I=4.49 wt. = 8.80

4 x 5.4# channel I=3.8 wt. = 5.4
5 x 6.7# channel I=7.4 wt. = 6.7

Basically, the higher the I value, the stronger the beam is in bending. However, rectangular tube is torsionally stiffer than channel. So again, it depends on the intended use and the design.

I added the weight (in lbs./ft). This basically shows why most trailer manufacturers use channel instead of tubing: more stiffness per foot weight of material.

Channel has the additional advantage of not buckling under the spring perches as opposed to unreinforced tubing.

i plan on starting my build soon also, i picked up a 30ft gooseneck POS the other day for free, i figure on using the hitch and completely re-doing it from the goose back. in researching it i found trailerplans.com and in my opinion the 40 bucks would be well worth it to get some professional plans. i will be ordering mine soon and will let you know how they are.. keep the good info coming

i plan on starting my build soon also, i picked up a 30ft gooseneck POS the other day for free, i figure on using the hitch and completely re-doing it from the goose back. in researching it i found trailerplans.com and in my opinion the 40 bucks would be well worth it to get some professional plans. i will be ordering mine soon and will let you know how they are.. keep the good info coming

You going with a deckover? or a low-boy?

im thinkin the 26'X102" car hauler, may end up going with the 32' flat bed as both the scouts end to end measure right at 26ft ..

i plan on starting my build soon also, i picked up a 30ft gooseneck POS the other day for free, i figure on using the hitch and completely re-doing it from the goose back.

whats wrong with it that you need to redo it?

as for the original question,my trailer is an old travel trailer frame that is made from 6"x2" box tubing,not sure on the wall.

its basically 17.5 foot of flat(first 1.5' is a toolbox and storage racks) with a 2 foot dovetail,with a 4' tongue. its got 3/16 steel diamond plate,about 2' wide down each side with an open center.

it weighs in around 2100 lbs,so yes,even your 14' trailer is
going to be heavy if you use box tubing and a metal deck.

whats wrong with it that you need to redo it?



thers a transmission on the right front corner of the trailer and the left rear corner rose up about a foot because it twists soo much. a little flimsy

[/QUOTE]Yea rectangle tubing 4"x 2" x 3/16" I have always called it square. As for my building ability I will post up some progress picks as soon as I get started to make sure it meets you high standard. Now as for the rectangle tubing would that be strong enough to get the job done.[/QUOTE]


This is what I ended up with a 5" C chanel trailer with wood deck but it pulls better than any trailer I have had. It is 12' long with torsion axles, brakes on both axles. Not much use for anything but my jeep but I guess that is ok.

looks good :smokin:

Nice work on the trailer. Jeeps must be little :D :p

This is what I ended up with a 5" C chanel trailer with wood deck but it pulls better than any trailer I have had. It is 12' long with torsion axles, brakes on both axles. Not much use for anything but my jeep but I guess that is ok.I recognize the Crawler Hauler :flipoff2:

I would reconsider a metal floor. If you ever want to work on your jeep while it's on the trailer (think clean surface while on a multi-day off-road trip) the metal will be too hot to lay on or touch for extended periods in hot weather.

i vote for tubing :p

IMHO higher torsional stiffness and less weight then heavy tapered leg (American standard) C-channel.

i made this 16' x 100" deck-over trailer some 6 years ago and it has spend most of his (harsh) life behind a truck conversion... http://www.v8rail.com/components/com_joomgallery/img_pictures/v8rail_1/crazy_train_10/crazy_train_20080729_1914342870_3_20080820_1594316 563.jpg

no cracks and the deck does not twist under uneven load.

i strongly believe in proper cross-braced tubing: structural stiffness = no flex = no cracks

main frame is made out of 2" x 6" x .120 , the deck cross supports are 2" x 3" x .120 H-beams that are finished off on the side with 3" C-channel

btw each tongue/main frame is made of one 20' piece; v-notched on the inside, bended and re-enforced with "diamond" stiffener plates ;)

...just my 2 cents :homer:

Seems to me 2"X4" box steel would be stronger than C-channel but thickness would play a factor here. My 16' 7k car trailer is 3" C-channel and i have had alot more than 5400 lbs on it with no problems. My 7k dump trailer is also 3" C-channel. My 18' 12k equipment trailer is 6" C-channel and is strong as hell. The only trailer that i have with 2"X4" box steel is my 14' 7k enclosed trailer "v-nose" and i have had 0 problems with that.

do you have any picks of the jeep on the trailer?

Show us your tow rig while you're at it

This is Steven we met on labor day weekend :flipoff2: you rolled about every 5 feet :flipoff2::flipoff2:

If we are not camping my to rig the the F250 in the Pic a couple post back If we are camping I pull it with a Gas motor home. That is the reason I did not wont any extra trailer. I will get a pic of the jeep on it next trip out.

I built mine using 2x4 tubing .188"

There's a few posts on here about it.

http://members.shaw.ca/hackers/trailer.html

It has held up very well over the last 4 years. It gets used a LOT. I haul a Bobcat mini excavator and a bobcat skidsteer at the same time. Its tight but they fit.