Box trailer tips and advice

[frbprado Lurker Find all posts View Profile Close frbprado]

The drawbar on my offroad camper that I built is 100x50x2.5.

The main cassis rails are 50x50x3 and the cross members 50x50x2.5.

Cheers Andrew

Okay, going with
Drawbar 100x50x3
Chassis Rails 50x50x3 (can upgrade to 75x50x3 if required, but really only wanted the 3mm so that the springs don't tear off)
Chassis Crossmembers 50x50x2

The trailer will be rated to 1400kg.

Thoughts?

[r4ndll Avid PP Poster! Find all posts View Profile Close r4ndll]

Brakes?

[gxl_d4d Advanced Member Find all posts View Profile Close gxl_d4d]

What sort of springs? Rebound springs are common on offroad trailers. The trailer will tend to bounce less with these as the rebound leaf provides some shock absorbtion. Are you getting shocks? What type of bearings are you using? Ford or Holden and parallel or different side inter and outer?

My trailer builder used Dexter bearings. They cost a fortune and are not the easiest to get so I'm hoping they last a while.

[sunchaser Member Find all posts View Profile Close sunchaser]

For your suspension check out these guys http://timbren.com/axle-less/
Pretty cool looking system using no axle. They look nice and strong and while I cant remember the exact price wasnt too bad and probably would cost about the same as buying an axle, springs, hangers, shockies etc. But you have to have some extra bracing underneith to support it. easily done while your building the trailer.
Cheers Gaz

[mjrandom Out of control poster! Find all posts View Profile Close mjrandom]

KISS principle. Get stuff you can buy at the usual suspects. So if you have to replace something you can easily.

EDIT: here is a how not to do it!

[Shovtel Junior Member Find all posts View Profile Close Shovtel]

Here is the link to a trailer we just had made: http://s1083.photobucket.com/user/sh...ibrary/trailer

Made from structural alloy - not normal alloy.

7x4 with high sides.
Internal tie down points
external tie down points
extra heavy duty/oversized alloy frame and walls.
flooring is the alloy flooring you typically get in utes. can be replaced if need be (though I don't know why we would need to).
4wd tyres
heavy duty suspension and landcruiser hubs etc...

The build quality is awesome. actually its a work of art. The guy who made it also made a custom ute back for my oldmans new hilux.

The guy who made it is located in Wollongong. Dingwall trailers. I would seriously challenge anyone to find a better built trailer around (just remembering its a box trailer).

Price - a fraction more then a similar quality galv trailer.

[shodown Senior Member Find all posts View Profile Close shodown]

Thought I would revive this one - I have searched but couldn't find the info I was after.

I have got my hands on an aluminium single cab tray that I'll be making a multi purpose trailer out of..... (carry quads, garden waste, soil)

Ideas for construction:
- Single axle same track as Prado
- A-Frame so that an additional platform could be mounted on A-Frame to transport a smaller quad
- Water tanks mounted underneath before and after axle - these could also be used for ballast for better weight distribution
- Brakes
- Alloy tray is rated to 1T
- Allow 250kg for trailer weight?
- Allow 200kg for tanks & ballast
- GCM of 1500kg?
- Spare mounted underneath
- Springs - eye to eye as previously recommended

Was looking for some recommendations on:
- Track width - what length axle is required to get same track as the Prado? Will this be affected by addition of brakes?
- What axle to go for? 1.5T 45mm "offroad" or 2T 50mm?
- Tipping - any recommendations on how to achieve this? I have a 6x4 tipper trailer that pivots from the axle, it doesnt get high enough angle to be TRULY effective.
- Hitch type, it a general trailer though there may be the odd occasion of taking quads to the beach / bush. Normal hitch or tregg poly block?
- Brake type, Hydraulic disc or drum? (I am favouring hydraulic so anyone can tow it if need be)
- Anything I have missed?

Cheers,
Kevin

[Symo Advanced Member Find all posts View Profile Close Symo]

I just went with 7x4 off road box, and added cage sides that are removable, and also got ladder racks that slot into the same corners. It has a longer draw bar, rated to 1.5T (no brakes on mine though) and I got the Polyblock hitch instead of the 50mm tow ball.

Does everything, with cages sides you can get a cover made to make it weather proof for camping, and you'll never run out of space, also means nothing in or on the car which saves you on accessories as well. Plus your not tied to the trailer.

Mine also has three jerry can holders and a gas bottle holder external to the bed. VERY HANDY.

The trick with this method is to have a decent large tent which mimics the speed and space of a camper trailer tent, I chose the Blakwolf cabin 450 with awning sides. 10 min setup and a darn site cheaper than even the shittiest of chinese import camper trailers, plus I can renovate and go to the tip with it so its not sitting in the yard rotting like a $10-$15k trailer would.

[mjrandom Out of control poster! Find all posts View Profile Close mjrandom]

Kevin, some thoughts...

No way will your trailer tare 250kg, probably 350kg and more if you go for a conventional tipping design rather than tip over axle.

You can measure the axle by calculating the hub to hub length from track and offset. Go to a trailer place and they will tell what length axle is required for that hub to hub measurement. Ish.

For an off-road trailer, especially the capacity you are planning a 50mm axle would be the minimum. Really heavy duty go for landcruiser hubs and bearings rather than Ford bearings and landcruiser stud pattern. If you're going to run factory alloy wheels allow for M12 studs and not the usual 1/2".

I like Treg hitches but there are a few similar styles. Be careful though with a tipper and a coupling that will allow 360 degree rotation. You can easily roll the trailer on uneven ground.

Tipping mechanism is complex and depends on how much material you are prepared to use and how you will effect the tipping action. The tray probably won't be strong enough without a subframe. Look at some others and copy!

I assume you mean override brakes? I would recommend electric brakes which are much more predictable and effective and fit a controller like the new Redarc Towpro.

[Pie Eater Lurker Find all posts View Profile Close Pie Eater]

This is a trailer I've built that has the rooftop tent mounted on top. I've added some other accessories afterwards like a fridge, bbq, esky etc.

[shodown Senior Member Find all posts View Profile Close shodown]

Thanks for the feedback.

Yes, will need to do some further calcs for total weight - especially once I have a design sketched up.

I guess if I go for 2T rated gear (axle / leafs, hubs etc) then it doesnt matter on the weight of the trailer, even if its 500kg it'll still be legal with a 1T payload.

I am looking at a subframe for the tray that will pivot on the end of the chassis, and collapse down with some guides to keep it sturdy on the chassis and some locking pins up the front. I just havent found any decent designs as yet.

I'll probably stick to standard hitch - I am not planning on doing anything extreme with it, taking quads out to the beach / bush here or there so I think Treg is probably overkill.

Main problem I see with electric brakes is the others cannot use it (to full capacity legally) without controller..... if the tare ends up around 400kg the legal 350kg payload is far its potential 1T payload.....

Cheers,
Kevin

Kevin, some thoughts...

No way will your trailer tare 250kg, probably 350kg and more if you go for a conventional tipping design rather than tip over axle.

You can measure the axle by calculating the hub to hub length from track and offset. Go to a trailer place and they will tell what length axle is required for that hub to hub measurement. Ish.

For an off-road trailer, especially the capacity you are planning a 50mm axle would be the minimum. Really heavy duty go for landcruiser hubs and bearings rather than Ford bearings and landcruiser stud pattern. If you're going to run factory alloy wheels allow for M12 studs and not the usual 1/2".

I like Treg hitches but there are a few similar styles. Be careful though with a tipper and a coupling that will allow 360 degree rotation. You can easily roll the trailer on uneven ground.

Tipping mechanism is complex and depends on how much material you are prepared to use and how you will effect the tipping action. The tray probably won't be strong enough without a subframe. Look at some others and copy!

I assume you mean override brakes? I would recommend electric brakes which are much more predictable and effective and fit a controller like the new Redarc Towpro.

[Gramps Advanced Member Find all posts View Profile Close Gramps]

I want to be able to use some 2nd hand Prado rims on my trailer but I'll have to change over the hubs. While I'm at it I might as well upgrade the axle as it's looking a bit rusted after 18 years of service. My questions are, what should I be looking to use if I plan on taking it on rough road camping trips? Are all axles equal?

Thanks

[mjrandom Out of control poster! Find all posts View Profile Close mjrandom]

Gramps I just bought my stuff at a typical trailer place. Not sure there is anything much between any of the various suppliers. If you are going to run alloy wheels get some 12mm studs for the hubs. ALKO sell them and most trailer places can get their hands on them. $1 each when I bought mine (including GST).

[AJ120 Out of control poster! Find all posts View Profile Close AJ120]

I want to be able to use some 2nd hand Prado rims on my trailer but I'll have to change over the hubs. While I'm at it I might as well upgrade the axle as it's looking a bit rusted after 18 years of service. My questions are, what should I be looking to use if I plan on taking it on rough road camping trips? Are all axles equal?

Thanks

I have been running a 45mm square solid axle with B type bearings on my campers for years, unless you're going really heavy this should be more than enough.

I have a brand new unused 45mm axle sitting in the shed that I don't need, it is the correct length for Prado wheel track. I also have a couple of second hand sets of 6 stud hubs with mechanical brakes.

Cheers Andrew

[zutta Senior Member Find all posts View Profile Close zutta]

Gramps, i am in close to completing my 7x4 box trailer build and have gone though Metal Market for everything i need, I went with 45 square axle as it will take a beating and rated well over my 750kg max trailer weight. I was thinking along the same lines as you with prado rims as mine are a bit crappy looking on the 120 but ended up getting a free set of sunny rims with 31x10.5 tyres on it. good luck with it.

here is my progress....