TOTU: Thrill of the Unknown Trailer Build

This trailer project grew from a need and desire to level up our camping and recreation game. We were tired of the daily tear down and setup of our roof top tent when we planned to stay in a location for more than one day. Also, on a trip to Yellowstone a few years ago, we took out kayaks and having them on the roof (over the RTT) presented another problem in which we had to take the kayaks off the truck before we could set up the tent every day or secure the kayaks to a nearby tree with cable locks in camp so they didn’t grow legs and keep our fellow campers honest.

A requirement for the trailer would be the ability to hold most of our toys, whether that be motorcycles, kayaks, bicycles, or future toys like quads or a side by side. Another and more important one would be mounting the roof top tent to the trailer on a rack. I like versatility in my tools, I want them to serve more than one function, and if they don’t, then they have to do a really great job at the one thing they do. The trailer has already seen a lot of use outside of our normal adventures. From hauling the motorcycles, to the trips to the hardware store, and everything in between.

Dimensions and Weights:
12'-0" Deck Length
5'-6" Width between fenders
16'-6" Overall Length
7'-6" Overall Width
1200lb Dry Weight (it's a pig!)
3500lb Axle Rating
2300lb Carry Capacity

1"x6" Ipe Hardwood decking material (beautiful and tough stuff!)

Current Setup:









So now on to the build!

 

The main structure of the frame is built with 2"x3"x.125" wall rectangle tube and the spanners being 2"x2"x.125"wall sq tube. I started by laying out the rough frame on the floor.


I used a 285/75/26 tire on 17x9 wheel with 4.5" back spacing for initial setup considering this would be the max tire size i planned to use.










The 2x2 sq tube is spaced every 2'-0" which will support the wood decking I planned on using.

 

Once I had the initial layout figured out it was time to align and tack weld the main frame and stringers. One thing I did change before continuing, was the rear "bumper" was shortened 1'-0" overall so the outside width would be 7'-6" (90"). This would keep the fenders at 12" past the deck and also narrowed the deck width by 6" to an overall width of 5'-6". I didn't want to be so wide as to be close to the max legal trailer width (108" as i recall), but also wider than the utility trailer I have been currently using (5'-0" wood deck).

I used wood chunks of 2x4s and a pack of wood door shims to adjust and level the outer frame, then tack welded the corners in place.



The stringers are flush with the bottom of the 2x3s as I wanted to recess the wood decking (I didnt know exactly what wood or thickness I was going to use at this point)



In hind sight, two things. I wish I had pre-drilled the 2x3 in the rear bumper for wiring, as well as the front corners. Or 45* chamfered the front corners. Either way would have worked, it just proved to be a bit of a struggle down the road when it came time for wiring through the frame.

 

Once the frame was square, I welded all the surfaces i had access to on the top of the frame, then used the overhead hoist to rotate the frame onto one side to weld the vertical portions of the stringers. This took a little bit of finesse and time by myself to safely rotate the frame around since i needed to do it twice, then place it upside down on the floor for the tongue portion of the trailer.








The tongue portion of the trailer is 2"x3"x.125"wall and extends 4'-0" past the front of the frame and extends 4'-4" into the frame, I wanted to be able to place a nice fillet weld onto this end instead of trying to weld right on the end of the tongue beam. The tongue braces are 2"x2"x.120" and go back at approx 30* angles, these angles took a little bit of work since my chop saw only cuts to a 45* angle.


Not shown in the picture below is the hitch mount, which i test fit to make sure the braces wouldn't interfere.



Once I was happy with the placement of everything, I welded all the edges I had comfortable access to. No need to get fancy when you can flip it around!





While I had the trailer upside down, I took the opportunity to position the Timbren 3500lb HD axleless system, I originally planned to not run a 2"x3" cross beam to keep my ground clearance to a maximum, but I opted for more strength in the end, as the bracing involved to not run a cross beam would interfere with the recessed wood deck I planned. Plus, I had to be realistic with myself, the truck will be bellied out way before the trailer even thinks about it!





And just for layout purposes....

 

Next step was to add support plates on the inside for the axle bolts so the frame didn't pinch when the bolts were tightened. The flip the trailer over and fully weld the added supports as well as any other welds that were inaccessible.









Then it was time to wrestle the axles into place and temporarily bolt them in place and put the trailer on its own weight.





This is when i realized I didn't want the tires sticking so far out and needed to find a different tire width and wheel combo.

 

Here's an inside look at the frame plate for the main axle bolts.



You can see where the 2x3x1/4 rect tube will go through for the major support of the axle.





Next up was the tongue jack. Due to the height of the detachable wheel, I wish I had lowered the jack mount by another 2-3". The flat base works perfect. But without a lift kit on the Tacoma, the wheel attachment is just a hair to tall to fully lower the trailer onto the hitch if parked in a weird spot. It hasn't been a major issue since most of the time I use the flat base when setting up at a campsite.

 

Next was to build the trailer outer platforms. These were 12" outside of the main frame and made of 2x2x.120wall sq tube.



The wheel gap should allow for a 35" tire, but for this style of trailer I don't think it's necessary. Unless someone feels they need to look cool.



Holes were drilled inside before welding so I could route wiring through the frame. If I did this again I would have mitered the corners to allow easier access. The visible welds at the corners and tops were ground flush for platform plating.

 

Maybe its just my computer but none of your pics are showing...

 

Thanks, I just checked on a different computer and yup, they aren't showing. Time to fix...

 

All fixed and up to date, thanks again @Minimag95 for pointing out the problem! Enjoy the pics!

 

Next part of the build was the fenders, which were made out of 1.5"x.095"wall sq tubing. I made a jig since I needed to make four of these.







Test fitting the first of 4.





I knew I wasn't going to be running this tire and wheel combo, so this was helpful to get an idea of tire width and backspacing that i need to start looking for. My Tacoma spare tire and wheel combo was almost perfect, I just wanted a slightly taller tire to match the current tire/wheel combo on the truck in case i needed to use a trailer tire as a spare and visa versa.



Also, at this time I picked up my Ipe hardwood for the decking material. The pictures don't do it justice....

 

Holy shit you built the whole trailer, looks great. In the 1st pic I thought you bought one from a trailer store and put a rtt on it.

 

Thanks!

 

It probably took more time to setup a jig than it did to finalize the fender shape and weld them all together. But it was worth the extra time spent.






Next was to weld in fender cross supports





The tedious work was grinding the welds flat and making sure the cross support was set back slightly and squarely from the edge for the fender cover material to come

 

After months of waiting in anticipation for the release of the Dewalt cordless Router, I finally got one in my hands! It's a pretty sweet machine! It does chew through batteries fairly quickly though.


These pictures are a little out of sequence, but I welded in 2" angle supports at the front and back of the frame for the deck boards. Apparently I felt the need to fully weld this across the length of the trailer! Next time i'll just stitch weld it, since it will allow extra area to drain any captured water.


Around the same time I welded up a front bump bar out of 2" sq tube.





As well as capped the sides of the frame tube. Looking back, I should have either mitered the main frame, or cut larger holes for the wiring to route through the frame, it proved to be VERY difficult to get the wiring pulled through the frame.



Time to trim the boards to length and put a 45* chamfer on the ends of the bottom side of the boards to clear the weld profile. I also put a 1/4" fillet on the top edge of the ends to help with future install and removal and to prevent chipping. I will say that if you're working with Ipe, be very careful not to slide your hand along an unsanded board, it is very splintery! I may still have some chips in my skin!
I took some of the off-cuts and drilled holes to see if I liked the look of bolting the boards down, but decided that it would be a lot of extra work compared to welding a full length "cap" across all the boards.


Next I cut holes for the tail/turn/reverse lights. I didnt realize at the time I ordered and planned for lights, that the trailer wiring was such that the turn/tail are in the same wiring. But I thought this setup looked nice for the few days i hadn't realized my mistake! I would also use a 4" tall rear rect tube next time as well, the rubber grommets would have fit much nicer.

 

While I was deciding how I wanted to fasten the decking to the trailer, I switched gears and worked on the stake pockets, which are 1.5" square tube, that accept 1.25" square tube, in hindsight, I think i would have gone larger and also, moved them up to be flush with the main frame rails, going down past that edge proves to be a bit of a pain when attaching things in the pockets. At the same time, I fabricated some tall cross bars for mounting the roof top tent to. I made them longer than needed for initial testing, and could easily slide them down to new holes in the tube and just cut the excess off from below to get the right height i wanted.

I also had taken the time to grind the welds flush on the outriggers in prep for diamond plate


Finding good spots and spacing for the stake pockets, I settled on 22" between stakes, I wish i have another pocket up further, or maybe all the way to the outside, but this would be helpful when using the outriggers for opening and closing the tent and just having a good place to walk around the trailer when loading and unloading equipment.



Prepping the pockets













Yes, they have a bit of a bow in the center, I didn't do a good job, if any, of clamping my work down before fully burning in the welds, so it sucked in the sides a bit.

I think I started out with 6'-0" from the top of the trailer deck to the top of the rail. which was way too high, I think I have trimmed a full 1'-0" off them now, and might trim another 6" off in the future.