My No-Weld Trailer project - Sort of

[bricke]

Hello everyone, this is my first post here after a few years of reading discussions and learning, I am Matt and I live in Norther California, moved here a few years back from Italy and after getting my toes wet with offroad camping, I decided it's time to build myself a trailer to haul my stuff.
It all started with a Chevy Silverado that was big enough to get us to our camp spot, then a Land Rover Disco 2 that prematurely died (still crying over it) and today with a FJ Cruiser that is NOT big enough for us now that we have a dog. So trailer it is.

I have started a year ago taking Oxy-Acetilene welding/brazing classes, then I got into MIG and after that I got myself into TIG classes, having all the hardware in my shop and a modest experience with Autocad early in my life, I began designing my trailer in CAD and I started tinkering with the idea of a no-weld trailer, kind-of stupid given all the time and money I put into learning how to weld but hey, I was bored ok?
Thought that if I fail, I can always weld it up and call it a day.

Countless iteration later, counteless back and forth with the company that cuts my steel, I ordered the first set of tubing, laser cut to my designs.

The idea is to have a bolt-on design using as much off-the-shelf hardware as possible, will have Timbren Axle-less suspensions and a removable tongue (for storage/safety).

From my calculations the rolling frame should be around ~700 pounds, I believe I overdid it, better safe than sorry I guess.

 

[high-and-dry]

My 5.5x10 frame plus tongue, with a dexter #10 axle with brakes should be under 500 lbs. It is all welded right now but no axle and I can lift it up on edge and turn it over by myself.

get some lighter steel and weld it

 

[bricke]

Steel tubing is 0.120
Gusseting plates are 0.250
Floors are 0.120

What is your tubing thickness?

It's too late now to reorder steel, next one I will definitely change design to make it lighter.
I will weight it once it's all bolted on and if it's too heavy I will remove the gusset plates and weld it instead.

 

[high-and-dry]

Steel tubing is 0.120
Gusseting plates are 0.250
Floors are 0.120

What is your tubing thickness?

It's too late now to reorder steel, next one I will definitely change design to make it lighter.
I will weight it once it's all bolted on and if it's too heavy I will remove the gusset plates and weld it instead.

The "frame" is .084 2x3 tube. The 3 tubes that form the tongue are .120 2x3 tube. No gussets needed as the tongue framing locks the front 3 cross members square.

totals is around 330 or so
frame is 126 lbs
tongue 102
angles running down the side to support floor and walls is 71
various odds and ends probably another 20 to 30 lbs

 

[bricke]

Everything showed up and I am starting to assemble everything.
I am using a Curt hitch as a receiver, if I am not mistaken it's for a Jeep Wrangler, the front tube fits perfectly and was drilled and reinforced to hold it. I plan to eventually also use a secondary bolt point for the hitch if there is too much flex.

 

[bricke]

Frame is assembled

I had to pass in some of the holes with a 0.5in drill bit as plates and tubes cutting tolerances are not the same and sometimes you are just unlucky. Noted for next build.

I got the Timbren Axleless suspensions too, my biggest mistake is that I build this thing too close to the ground... I will have to raise it to install the suspension, gotta get creative.

 

[high-and-dry]

That trailer will be IED rated.

As for raising it up bolt ( weld ) on some 2x3 rect tube where the axles go, that will lift you 2 inches.

 

[bricke]

I meant that I am assembling it too close to the ground, once it's bolted together it will be heavier and more cumbersome to lift, I have to raise it another 2ft to be able to install the suspensions...
I'll have to use all the jacks that I own

 

[old_CWO]

The hex bolt heads sticking up on the deck floor would be horribly inconvenient when loading gear; is there a solution planned for that? You obviously spent a lot of time with your plans but I think you are doing something needlessly complex and heavy for the intended application. I mean if you're hell bent on a bolt together trailer, Harbor Freight already had a kit for ya

 

[bricke]

Yes, a wooden decking that has been cut to shape goes in it, that will give me a flat floor.

True again, HF has a bolt on frame, I wanted to use that same idea, just in a better format (not wonky C-Sections tubing).
I am already designing a new plan for my next version that solves some of the bolt-on design downsides. I wouldn't hate being able to manufacture this on a larger scale in the future once all the kinks are ironed out.

 

[john61ct]

Lightest possible weight for the minimum required strength is the #1 design parameter.

Not just for reducing the cost of the trailer, but fiel savings worth hundreds or thousands of times more

allowing it to be pulled by ordinary vehicles, wear and tear on those being a **much** higher cost than any of the above

and in general just making it much more useful and potentially attractive.

Hiring an experienced engineer should be priority #1 if even dreaming of any commercial possibilities.

 

[Teardropper]

How will you paint under the gussets?

 

[bricke]

@Teardropper: I have to take it apart, paint each part and then put it back together.

Wheels are installed.

I weighted the full rolling frame, with suspension, tongue, wheels and tires (265/65R17), I am at 570lbs, tongue weight when unloaded is 60lbs, I am at 10.5%

Considering that I way overshoot it with how beefy everything is, I am surprised it's not heavier. I was planning to make the main box in aluminum but I am thinking to simply weld one in steel, should add another 100lbs maybe.

Thoughts?

 

[high-and-dry]

My recommendations is to take the deck plate off, and weld it up. I dont know what they plate weighs but if you weld it you wont need the plate.

What size it the deck, I dont think you ever said 4x8?

 

[bricke]

Deck is 4x6

I calculated a 700lbs of a bare frame, that was way off, total rolling frame with deck is 570lbs, wheels and tires are 130lbs. That would put the frame+deck+suspension at a 440lbs, believably the only frame+deck is less than 400lbs.
I am tempted to weld it up and lose the bottom gussets and the bolts as that will make it easier to install the box more than improving weight - that I honestly believe it's pretty good given this is all 0.120 tubing (2x2 and 2x3)

What would a beefy (like a M416) 4x6ft trailer weight when empty? I believed they were around the 550lbs mark, am I wrong?