a1gemmel builds an offroad trailer from scratch

[a1gemmel]

Let's build the trailer box frame.

Pieces:



Parts:



Welded up:



Voila! Four rivnuts and M6 bolts hold the box to the frame. Punting on how the propane tank will be secured for now.



Then the whole trailer gets flipped over to stitch the floors to the braces and weld up the bottoms of all the pieces added on after the initial frame construction.

[TyTheJeepGuy]

Just gets flipped over eh, just like that?

[a1gemmel]

TyTheJeepGuy previously posted:

[TjMike]

a1gemmel previously posted:

[a1gemmel]

We're back from a week haitus of replacing the heater core in the lady's truck - hot tip, if the heater core ever springs a leak in your GMT800 just scratch the VIN off and set it alight in a walmart parking lot, whatever the consequences end up being will be less trouble.

I had a hell of a time trying to get the uprights and the top of the box square in all directions. I own a welder, that doesn't mean I am one. The tubes just want to pull all over the place when tacking them in. Then I realized I could cut the sheet metal piece for the front of the box and use that to hold the frame square to weld it up, then it was smooth sailing. All parts of the box are within 0.2 degrees of the desired angles, so I'm going to call that good enough.



I also finished welding in the last of the patchwork floor.

[a1gemmel]

I'll throw this out here to solicit opinions, since I'm not quite sure about what I want to do - I have a tankless propane water heater to put in the trailer for hot tap water and showering, but I'm not quite sure where to mount it. Haven't found a lot of info online about putting it in an enclosed space, venting requirements, etc. This isn't a person-carrying trailer so I'm not concerned about carbon monoxide, more just heat and moisture management.

Option 1 - Put it inside the front half of the trailer. There will be a steel bulkhead separating the front and rear half, where the floor seam is in the pic above. I'd mount it on that facing forward and fab a heat shield to keep things in the storage compartment from touching it. I think I'd need to put a vent on the top of the trailer, making that rainproof could be challenging. If this puts off a ton of moisture, it could make things in the storage compartment soggy.

Option 2 - I've seen (but can't find again) a pic of someone using a pelican case mounted on the outside side of their trailer with the heater inside it. You just open the case to use the heater. I would mount it behind the driver side tire. This seems like a safer option, but it does take space I was planning on using for a jerry can. I like the thought of having a safety switch that only powers it when the case is opened.

Option 3 - ???

Typing this out, I think I know which option I'm leaning towards but I'd be interested in hearing other opinions too. Never done this before.

[Jeffcon]

a1gemmel previously posted:

[a1gemmel]

That's great info for the venting and winterization, thanks Jefferson! Do you have any insight on the ambient heat that the heater creates in the space?

[a1gemmel]

I've been eyeing some vevor pipe-heating cable, it looks like people have had success with wrapping water lines with that to avoid freezing in winter. At 5w-ft it's seems like my solar system should be able to supply it easily, but of course actual testing will be required.

[Getaklu]

Just be mindful of the inrush current for self-regulating cable. Short duration, but quite a load. Once on, it is good as it pulls only what it needs power wise.

[Jeffcon]

a1gemmel previously posted:

[a1gemmel]

Got tired of dragging around a jackstand every time I move this thing, so I finished the tongue jack part of the program. Just a harbor freight swivel jack with an extra foot of tube lazily welded on.



Next the sides got clamped in place and tack welded on. Then I plasma cut out the door, thus making the door panel skin without having to measure anything. This turned out to be messier than the labor it saved, so for the other side I traced it with a sharpie, and took the panel off to cut it out with the portable dry cut saw.

[a1gemmel]

Ty earns his lift time helping hide my terrible welding from the world

[TjMike]

Coming along nicely. Think it will be ready before the end of the summer?
Ty just helping so he can borrow it

[a1gemmel]

I'm going to have to really jam on it to get it "done" before the trip I want to use it for in August. Well, it's for sure going to be usable as a trailer for that, just maybe not with all the bells and whistles.

I just picked up a new (old) Fray 10R mill, so I had to use it entirely unnecessarily to make some miter cuts.



The doors get fit up using some paint stir sticks to provide spacing, then welded up in place.



Tacked to the cutouts from the previous step, which holds their shape for finish welding.



Now there's two of them!



Then I welded the front half of the roof on.



The underside gets stitched onto the frame.

[a1gemmel]

The side doors got riveted on with piano hinges. Frankly I don't really like how this looks so I might revisit it with the same style hinges I'm using for the heavier panels.



In a bad design flaw, there's nothing triangulating the sides of the trailer at the rear. They warped about 3/16" outwards from all the welding, but a come-along worked for tweaking it back closer to square.



I got these heavy duty hinges on eBay, I think they're meant for trailer ramps but I realized that using them as-is requires mounting them opposing and the panel cannot be removed. I chucked them in the lathe and drilled and tapped for an M6 bolt, such that they can be mounted in the same direction and the panel can be removed, but retained by the bolt and a washer.



The "lid" is fabricated in place and then has hinges added. The flat bar will be drilled and tapped for the solar panel mounts.



Same news for the tailgate.

[a1gemmel]

Fenders are now attached with 3 M8 rivnuts per side, and a 5 gallon gas can is mounted on each rear corner.



Gas cans mount via 4 M6 bolts tapped through these steel straps. I hope this is going to be enough strength to not bend outwards when bombing down washboard road, time will tell.




And I've been wanting to do this for a while!

[TyTheJeepGuy]

Don't get duped into those timeshares from the lift salesmen its never worth it

I think we need to see the lil snowmobile trailer on the RTI ramp for a good comparison.

[a1gemmel]

The lid now has the holes for the solar panel mounts drilled and tapped, and a pair of gas struts. Toggle clamps hold the tailgate shut.



I decided I am going to replace the piano hinges on the front doors, so I turned up some hinge pins on the lathe.

[a1gemmel]

I bent and welded a strip of 1/4" steel around the inside of the front door holes. This will get a gasket on the outer surface that will be squeezed by the door when it's closed.



The doors themselves are welded back on using the hinges I machined. They can be removed by just lifting them upwards.



Test fitting the contents to help visualize the fit-out of the internals.