Off-road teardrop scratch-build

[rob cote]

Hi. I'm Rob. Perhaps you gathered that from my username. Mandy will probably chime in here at some point. We're building a teardrop from scratch. Perhaps you gathered that from the title.

This is what's going on. It will have a queen size bed because I'm tall, and we have a large dog, who I'm sure you'll see here. He takes up quite a bit of space, and most times a queen seems a tad too small. The trailer will have a grill, of course. And a fridge/freezer. It will have an outdoor shower and support equipment (propane, water tank, and water heater). It will also have a sink. The trailer will be off-road capable and has decent ground clearance (~20" if I remember correctly).

Anyway, you probably came here for pictures, so here goes.

This is a very early design we had looked at:

It had a hatch at the rear which we didn't love, so we scrapped that. I've read enough stories here and elsewhere of water leaks around this hinge to stay well away.

We were also concerned about tongue weight, so we moved the fridge to the front here:

We made a full scale mock-up of the layout as a sanity check, to make sure the height of the galley was in the right ballpark.

This layout had the grille and sink "stacked" but on separate drawer slides, so the sink would pull out beyond the grill for use. I thought this was clever, but I had a really hard time finding a good faucet option that wouldn't be super tall.

We were concerned about overall height of the trailer, so we moved the sink out from under the grill to bring everything down a bit:

This isn't exactly where we're headed, but it's pretty close to the final design. Of course there are constant changes to the details, but the layout has been pretty constant for a time now.

So we got to work on fabricating. Well, not quite. We got a whole bunch of tubing that was reclaimed from Rockingham Park in Salem, NH. Since it was used, it needed some cleaning before we could do anything with it. So all the tubes got a bath in rust remover, and then in paint.

We used a big PVC pipe with a cap for the rust remover bath:

Then took off the old paint with an abrasive wheel on the drill press. Here you can see (left to right) before - after - during:

Then the tubes got filled with a rusty-metal primer/sealer, the excess dumped out, and left out to dry. We're in New England, so as much rust-prevention as possible is maybe barely enough. So once all THAT was done, we got to fabricating.

 

[rob cote]

Armed with the latest of our drawings, we chopped up the tubes to form our basic ladder-frame structure. I laid everything out on the floor (because it was the largest flat reference we have) and welded the frame.

It came out within 3/16" of square down the diagonals, so we called it acceptable. We ordered a 3500lb. axle, and we got springs and mounts from a friend. The springs are 2000lbs., which may end up getting swapped out if we're too light, but they work for now.

I made up a bunch of brackets to allow us to bolt things onto the frame (shown here without weld nuts):

And I burned those into the frame:

 

[mandy_]

Hi, I'm Mandy! My job was to approve the design, take progress pictures, assure safety, and entertain Loki (the dog) during the build process. I assist when needed but really just try to stay out of the way!

 

[rob cote]

Lesson learned: it is much easier to finish the brackets before putting them into place. So I made up a bunch more brackets:

It goes much faster when working in "production" mode. Rather than doing a task once, and then moving onto the next, I can get setup for one operation and repeat it 10, 20, 30 times before moving onto the next.

Anyway, those are used to hold in the floor like so:

And also the walls and other things:

So I made up a few batches and threw them into a bucket to have a supply on hand as needed. It's been quite handy to have. So far, everything besides the suspension hardware is 3/8-16. The goal is to minimize the array of tools required to perform any removal/repair work we might come across.

 

[2180miles]

Looks great so far man. Definitely looking forward for more updates, and to finally see this thing on the road. What're you thinking for a finish timeline... Will we have it for the expo trip this summer?

 

[rob cote]

I already told you that we'll have water on board. Here's how. We got a tank from plastic-mart.com. I don't know if you're familiar, but it seems like a great resource; they have a huge variety of tank volumes and shapes. Ours is 20 gallons, so about 160 pounds full. It's probably the heaviest single component, so it mounts in the center of the trailer down low, like so:

The representative at plastic-mart that I spoke with on the phone said the bottom face of the water tank must be fully supported. So I laid out the skid plate:

The cutting is tedious with a cutoff wheel, but it works.

Blast some holes in there for water drainage...no not THAT water silly. And then stitch it in:

So then the water tank just needed a hold-down. I made up a simple frame out of angle:

And it fastens down like so:

 

[INSAYN]

I like your mapping things out on the wall with blue tape. That can really bring things into perspective and give you a feel for reality on how things will be for real.

Out of curiosity, are you welding with flux core?

 

[cparkerc]

I like your mapping things out on the wall with blue tape. That can really bring things into perspective and give you a feel for reality on how things will be for real.

Out of curiosity, are you welding with flux core?

Sure looks like it, I am too and it makes a mess!

 

[rob cote]

Yes, I'm using flux-core. The extra heat is helping; I didn't love the amount of penetration I was getting with solid wire.

I highly recommend the blue tape method. We found that the grill top was within an inch of our stove. Then we moved it in the design, but it's still really close.

 

[rob cote]

Our heat source is propane. We worked out the early drawings to leave space for a 30lb. tank, knowing that it was probably way too much propane. But we figured it's better to have more than enough space, rather than not enough. So when we got ready to buy the tank, we went with a 30lbs horizontal mount tank because that's what the drawings showed. Then a day later, we changed our minds and decided we'd use a smaller tank. We tried to cancel the order, but no such luck. We waited to receive the tank from Amazon, then attempted to return it, but no such luck. UPS told us that they couldn't ship a new empty propane tank citing DOT regulations. I explained that they had just shipped it to me the previous day, but that was worth nothing. I explained the situation to Amazon and they basically said, "Keep it and we'll refund you the full amount." So that is the story of how and why we have SO MUCH propane. The upside is that I suspect we'll have to refill it very rarely.

So we found a home for the propane tank just behind the water tank. Setting the tops of the tanks flush with one another, we found the propane tank would hang down below the frame a couple inches. So we drew up a skid plate/mount for it to attach to two frame crossmembers.

Now, I've been lucky to have most of the tools I've needed for this project already. I've bought a few small-ticket items along the way. But I couldn't justify the cost to buy a sheet metal brake to make this one part. So we decided to have it made for us by a local fabrication shop. Since we didn't want to have to pay twice, we made up a cardboard model to be absolutely certain the drawing was correct:

You can see this project has overflowed into the kitchen quite regularly. Anyway, the model confirmed we were in the right ballpark, so I cut the sheet metal blank and brought it to Mikes Welding in Revere, MA with our drawing. For $10 per bend, he gave us this the following day:

Which is far better than what I would have been able to come up with without the proper equipment. We were shocked with the turnaround time as well, because it was only a day or two before Thanksgiving, as I recall. We definitely recommend them if you require any fab work.

So as you can see I had to notch around the receiver tube to make it fit. No big deal. It otherwise fit like a glove.

So I cut up some trapezoids:

And tacked them into place:

And triple checked that the tank fits:

Finally, I wasn't comfortable simply through-bolting the skid plate hardware for fear of crushing the tube and not getting a good clamp load. There's also greater potential for the hardware to come loose over time. So I sleeved the mounting holes like so:

And made some flange nuts just in case the sleeves were to fall out:

I didn't want to be relying solely on the welds that hold the sleeves in place. And by welding the washers to the frame crossmembers, we'll be able to remove and install the propane tank skid plate from underneath with only one wrench.

 

[krick3tt]

When I am welding nuts to something I screw in the bolt to keep the internal threads clean of weld splatter...but then I am not that great a welder.

 

[rob cote]

When I am welding nuts to something I screw in the bolt to keep the internal threads clean of weld splatter...but then I am not that great a welder.

For the brackets I made, it wasn't really an option as I would have had to drill the holes first, but no great way to locate the holes perfectly. For welding on the washers to the nuts, I could have put them on a bolt, but I didn't have any on hand. Everything gets the threads chased after welding, and it hasn't been much of an issue. I just put the tap into my drill and run it in, then back out again. Doesn't take very much time to do it, and the bolts all go in great afterward.

 

[rob cote]

Huge thanks to our friend Ryan, who generously donated a set of wheels he was no longer using. They were in a sorry state, but they were round and probably held air, so we were thankful nonetheless. I bolted one up as soon as I got them home, just to see.

I was slightly worried I had maybe spec'd the axle too narrow when we had it built. But seeing the wheel mounted up did wonders to quell my fears. It looks like there's plenty of clearance. So we got to work on cleaning them up. A warm shower took off the loose dirt and grime that accumulated from too long outside.

It also gave us a better idea of what we were actually up against:

We don't necessarily need to have a show-car quality finish on these, but we wanted to put in a little bit of effort to make them more presentable. So we scrubbed them down with a scotch-brite pad, or whatever it's called. Plastic wool? This knocks down the high stuff and smooths out the roughness where there is surface rust. To a degree, anyways. It's certainly not perfect. Then they each got primed with a rust-converter/primer. Then the insides got painted black, and the outsides got painted silver.

So with the wheels all set it was time to talk about tires. In order to set the height of our galley correctly, as well as to have good ground clearance and off-road capability, the trailer was designed to ride on 30" tires. We shopped around a bit and found a good price on (3) Falken Wildpeak A/Ts in 30x9.5x15. They seemed to have good reviews as well, so we'll see. To keep cost down, we decided to mount the tires ourselves. Let me be clear here; I wanted to see what it was like, and Mandy said "okay whatever". Or something to that effect. In hindsight, I would not recommend this. Leave it to the professionals. I got to here:

And I had to call in reinforcements. Apparently I did it backwards. It sucked. But our neighbors, wonderful people that they are, accept payment in beer (which we happen to brew!) so in the end it all worked out. We probably saved a few dollars, I dunno. It wasn't really worth the effort though. But at least now I know what it's like to mount a tire. I've wondered for years, as it's always a situation where I hand over wheels, tires and money, magic happens behind a door, and then I receive back tires mounted on wheels. Anyway, we're pumped with the end result:

 

[2180miles]

Those rims look infinitely better than they did sitting in my backyard. It's absolutely great to see them being used and cleaned up.

Between the welder and rims and my general sense of humor throughout all this, I want my name engraved on the nameplate with the design team.

 

[indiedog]

Hi Rob, welcome to ExPo. Looks like you are putting a lot of thought into your build, certainly better to do it before actually building it. One thing I'll note is that your rear spring hanger looks like it should be placed further back as shown in photo no. 1 in post 13 above. Typically the shackle section is vertical or slightly angles up towards the rear of the trailer, not angled towards the front. Pretty simple fix.

Keen to see things progress. Brad.