Optimum dimensions of trailer?

[The Adam Blaster]

I'm strongly considering getting a custom trailer made.
It wouldn't be for camping out of in the immediate future, but at some point down the line I'd like to be able to use it for that purpose.

With all of the custom builds in here, what dimensions have you guys ben using for the main box of the trailer?
Part of my needs would include hauling 4x8 sheets of lumber/plywood and various other building materials, so I wouldn't want it too short.

Is 4'x6' a decent size or would that start approaching being too big for the trail?

 

[The Swiss]

Mine is 4x6 and it works very well. What IMHO is equally important is that the track width of the trailer matches the track width of the vehicle you are pulling it with.

 

[The Adam Blaster]

Well, I'll likely be pulling this thing with more than one vehicle, and chances of that increase the longer I would own the trailer.
But, for the trail duties, it's a pretty good chance I'll be pulling it with one of 2 Cherokees, but one is lifted had has high offset wheels, the other is bone stock. I'll probably design it to fit the bigger of the 2 Jeeps because the "road" conditions that I encounter with it will be worse than the stocker.

 

[greentruck]

For hauling 4x8 sheets with our M101 CDN, I made a simple frame out of 2x4s. It sits on the lip of the trailer bed, with short blocks at the ends of the 2x4s to hold the sheets in place and to lock it in place over the bed lip. Once I have the sheets on, I throw a couple of binder straps over the whole thing and away I go. Takes about a minute to walk to the back yard, get it, and lay it on top of the trailer to be ready to haul.

That works well for the occasional trip to the big box. If you plan on regularly using your trailer for such work, I would go with a bed that will big enough to hold the 4x8 sheets. A trailer that size really isn't going to limit you on the trail IMO.

 

[pkelly72]

It is a really good question.

 

[java]

inside of the box being 4' so the ply fits inside, and 6'6" for me personally. just so my dirtbikes fit nice.
that way the ply will sit over the tailgate and in the bed at an angle.

also having a couple to center of axle length close to the tow vehicle is nice,makes the trailer track the same around corners.

 

[The Adam Blaster]

I've been doing some rough drawing and measuring...
While I think the 8' trailer box might be a bit long for some trails - the fact is most of it's use will be around town for "work" stuff. And an 8' box (or just a tad longer) would be pretty nice to have.
I want to store at least 1 jerry can, and 1 spare tire on the side of the trailer, in front or behind the wheel well on the exterior of the box. After making up some sketches, a 6' box leaves very little space on either side of the wheel well for this type of storage.
I'm also going to be designing the trailer to handle 33" tall tires because that is what is on my trail rig. I can buy 3 other tires/rims that are much smaller to stay on most of the time.
So, designing the trailer to have wheel wells (and fenders) large enough to handle the 33's limits me a bit as well.

 

[greentruck]

Just so you know you perhaps have a good example from other designers to use for inspiration and measurements that's easy to evaluate near to you, the M101 CDN trailer can handle up to 33" with the stock suspension set-up.

 

[The Adam Blaster]

I haven't seen an M101 in person, but the trailer I want to design and have built is going to be more utilitarian, and more multi-purpose.
I sure wouldn't mind taking some queues from a proven platform though...

 

[hugh]

My trailer is just a bit over 8 feet long, I know it,s not the type of trailer you are looking at but the length fits your question. I made it pretty much the same width as my Cherokee and it follows the XJ pretty much anywhere. The stock XJ mirrors give great visability. The entrance to one of my favorite off road and camping spots has a tight couple of corners followed by a 5' deep gully, all rock that requires my XJ to have 6 1/2 " lift and 35" tires to clear without scraping. The trailer runs on 31 " tires and also does not scrape. The first picture the trailer is green and has a 48" wide axle. On the 3rd trip in I went a bit to fast and it tipped over. So I upgraded the axle to 3500lb,s , added electric brakes and shocks and widened the stance to move the wheels outboard of the trailer. I gained a bit more than a foot of wheel width which made it way more stable. It also got a white paint job. Before I built the trailer body It was left as just a flat trailer so it could get a test run. The last 2 pics show how that went.

 

[The Adam Blaster]

Thanks for posting up Hugh!
I've got a couple questions for you:
That tapered rear end, is that included in your 8' length measurement? (Mne is going to be the same shape as a regular utility trailer with a flat bottom.)
What was the distance between the hitch and your axle, and did you place your axle dead center on the trailer?
Also, do you have a link to your build thread, do you have a build thread?

 

[SWITAWI]

Not sure about 'optimum' dimensions per se, but I did a lot of looking at off road trailer websites before settling on what I wanted for a multi-use utility trailer. I found that most of the expedition/offroad trailer manufacturer's (AT, Afrispoor, New Image, Sierra 4x4) overall lengths ran from 8ft 6in to 12ft 6in, and overall width varied from 5ft 1in to 5ft 10in. Ground clearance varied from 14in to 24in and only one manufacturer listed their drawbar length, which was 2ft 8in. The main cargo box measurements varied from 40-49 inches in Width and 54-84 inches in Length.

Since I knew my uses were going to be 90% just hauling crap I figured overall length wasn't as crucial to me. I found a used utility trailer with a 4'x7' box and a drop-down tailgate, but the tongue is so short it gets pretty lively when it is empty. I plan to basically double the length of the trailer with an extended drawbar and tongue platform so I can have a permanent spot for onboard power, fuel cans, water, propane, and a spare while keeping my empty box for wood, gravel, moving to a new place, camping gear, or whatever. The additional front length should help quell the towing jitters as well. And since I feel the trailer is too narrow as well I would like to widen the trailer with side platforms and extended fenders to accommodate a wider axle to match the track and bolt patterns of my tow vehicle and that should make it even more stable. Maybe I should have started from scratch, but it will be fun once I get a chance to finally start...

:safari-rig:

 

[The Adam Blaster]

Switawi, that's kind of what I'm going to end up with - a multi-use trailer that is most often used for hauling stuff, usually building supplies. After I started thinking more seriously about this, I realized that the most use the trailer would see should dictate the size of this thing.
The general size I've got for the box at this point is 56"x102" <- outside dimensions, about 4" shorter and narrower for the inside dimensions due to size of square tube that will make up the supporting walls. (2"x2")
My thinking is that I used to have a cheap utility trailer (Snowbear) that was advertised as 4'x8', width was fine but it was actually a touch shorter on the inside. It was a real PITA when I was transporting sheets of drywall and was always worried about the ends and corners getting squished. Having a couple extra inches of width and length will make things a lot better.
(That's what she said!)

I also want to extend the fenders into platforms in front and behind the actual wheel wells. I'd like to mount the jerry cans and spare tires in these locations, then have a nose box for other incidentals like straps and batteries. I'll probably divide the nose box in half, batteries and inverter on one side, strap and tool stowage on the other side.
The platform to hold the nose box will be tapered in to the center somewhat, I've been thinking it would protrude about 24" in front of the main box.
The tongue would extend approx. 36" in front of that, giving me an overall length of the entire just shy of 14 feet.
I would also like to make the tongue adjustable, so I could remove the very front section to shorten it a bit for offroad use.

I'm just getting all the basics sorted out right now, so if some of my posts on this subject end up reading as being a bit disjointed, or even contradictory, you'll understand.