20' Enclosed Race Trailer "Build"

aMaff

High Speed Low Drag
:
1992 Miata / 2003 Pathfinder
Figured this would be an ok place to talk about building out the new-to-me race trailer.

With the kids getting to about the right age for it, we've added a Kart to the fleet, and very quickly realized we'd be able to take either the race car, or the kart, but not both. A buddy of mine had just got a new trailer, and his came up for sale.
The AC and canopy made it an easy sell to the wife, which'll mean we'll be able to camp out in it too. It's big enough to haul the entire fleet, as it were, small enough to still fit in my driveway, and not TOO much weight for the Armada to pull.

The trailer is, essentially, a great blank canvas at this point. A plain 20' box with an 11,000 BTU AC on the roof.

We're upgrading from a 16' 'home built' from an RV frame open trailer:




And we've now replaced that with a 20' Haulmark Race Hauler trailer:




The interior has a few electrical outlets, and a couple of fluorescent fixtures.





Plans in approximate order

1. Electric tongue jack to replace the too-short jack who's handle broke immediately upon arriving home. I had to stack about 8" of lumber under the jack to get it off the ball on my hill (more on that later), and that just ain't gonna cut it. Since I need to replace the jack anyway, going electric is a no-brainer.
2. Paint the walls white. The plain wood is just dark and dreary. Just like with a garage or workshop, white walls help enhance any lighting that you do have.
3. WD hitch and shorter diff for the tow pig. It pulled it ok on the trip home from buying it, but it could use more gear. It'll need a WD hitch in order to pull this thing loaded.
4. E-Track, just, everywhere.
5. Electric winch, which will require welding a plate under the trailer floor to support it, and adding a tongue box to keep the battery.
6. Solar charger for the battery.
7. Tire rack / workbench.
8. LED lighting in the interior.
 
First thing was getting it home from SC and making sure I can park the damn thing. Parking the 16' trailer on the hill to my shop wasn't TOO bad. This is...well, a little sketchier.

Because the trailer is 4' longer than the old one, the Armada sits further up on the flat part of the driveway when unhitching, so the ball is further up in the air (because of geometry), so getting the coupler off the ball with the short 'stock' jack was an adventure. But we got it done. Here it is in its new home:



Of course, immediately upon unloading it, the jack handle broke:



It's a bit weird being in the workshop with this thing looming over you:



Next, EVERYTHING needed to come off the wall for cleaning then paint. Those fluorescent fixtures are going...dunno? To a friend? To be donated? Not sure yet.



I figured out why the shore power plug cover was all janky and wouldn't close. Basically because someone took out the recessed, hard mounted power inlet, and then replaced it with an extension cord plug with some romex sticking out the back. Since I've got everything out, that's getting replaced.



Finally, after getting everything off the walls, they got washed down to knock off the "race cars have lived here" dust and grime to prep for paint. It'll dry out the rest of the week, then primer and paint will go in this weekend.

Luckily the rear door clears the top of the shop door opening, so I can get a fan in the back without clogging up the entire driveway.



 
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I replaced the breakaway cable because the one on there was super frayed (and poked you in the fingertips every time you went to move it). Once I took the electrical tape off, frayed wasn't even really close to being the issue.



It's basically a broken knotted mess. So, into the trash it went.




Replaced it with a shnazzy new coiled cable with a much beefier carabiner, and replaced the tiny carabiner that was securing the coupler tongue with a new 5/16" pin.

 
Grabbed a tongue box and BigAss(tm) Deep Cycle battery to run the winch, electric jack and lights:

 
BEHOLD MY ERECTION!
No wait, that can't be right...




You can kinda see the source of the height issue here. With the tow pig up higher on the flat, the ball hanging off the back is higher up off the pavement. With the old trailer I could roll another 4-ish feet back, which effectively lowered the ball several inches relative to the trailer:



Plenty of height now. Rigged up to work for the time being, I'll get the tongue box mounted and the battery in it eventually, but this works temporarily:

 
Thanks Mahk!

I finally pulled my head out of my ass and hooked the trailer jack up to the 12v hot in the trailer wiring's junction box coming from the truck's bumper.

I also did some testing w/ the rear hatch, because there was some concern it might hit the much taller electric jack. On the WD hitch, there's plenty of clearance. It'll be close on a normal hitch, but I'll plan around that if needed (I'll test that at some point).

 
Prepping for paint is a massive pain in the ass, but it'll be worth it.

 
Even with a single coat of primer and lit by one drop light, it's so much brighter in there. I'll slap on a coat of paint tomorrow and it ought to be be plenty good enough.

 
Got a bunch done on it today.

Paint went in this morning. It's kid approved :D






Found a "small" issue with the tongue box. In that...it's smaller than the tongue of the trailer. I had assumed that these are a standard size but that appears not to be the case. Oh well. Regardless, it was cheap and it's big enough to do the job, so it's going on:




Plenty of room for the battery box. I'll drill a couple more holes and bolt that down tomorrow. After that it's just a matter of drilling a bigass hole and running the wire and circuit breaker for the winch (which I'll need to scavenge off of the truck tomorrow).



I had enough clearance, just, to clear the battery for the breakaway box, but I didn't like how close the wiring was to the threads on that bolt



...So I fixed it with some wire loom. I didn't have any big enough for the whole bundle of wires, so....




Stupid like a fox :lol:
 
I got the battery box and winch mounted, the loaded a BUNCH of s*** (including a couple 45 lb weight plates) into the trailer and got the weight distributing hitch setup on the truck, basically a worst-case scenario for weight. It should never be THAT much stuff (like, any event where we're taking most of that stuff, we probably won't have the kart right on the nose, that kind of thing). That process was a WAY bigger pain in the ass than advertised, but we've got it well within spec for F/R axle "droop", which will help a ton. Took us about 3 hours, but we got it done. The electric jack was worth EVERY penny today

With the winch, I opted to drill 2 of the bolts directly through a frame member, and then put 2 of them through a really overbuilt spreader plate under the floor vs getting the welder out. If it turns out to be an issue I guess I'll end up tying it in, but it's likely already way overbuilt for the little weight I'll be pulling with it.

I will say I was surprised at the room we had. With the Miata, we got the rear all the way up to the flat (off the beaver-tail), and with the kart up front still had plenty of room to move around at the front. Looks like this will work out nicely for us :toast:
 
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I was absolutely wiped after putting the hours in this weekend, to the point where I didn't even unload the trailer, just left it there last night. I took a few shots this morning to give a feel for the room I have to play with, along with holy s*** how much sag the rear of the Armada has with the tongue weight. Which, again, was setup as a worst case scenario. Weight bags for canopies and that sort of stuff would, when loaded in a sane way, be put near / over the trailer axles, and not all the way on the nose.

No WD bars:



With WD bars. For some reason this thing always looks low in the rear, but there's ~1/4" difference in sag between the front and rear axle:



I'm going to need to put a couple more D-rings in front of the kart, or tying the car down (and winching it up) will be a nightmare, but that's easily done at this stage. There's enough room that the kart could move away from the wall front wall a little and still be comfy:



And in the back there's room for a few sundries as well. Of course, there's no E-track up so it's all pretty haphazard right now, but you get the gist of it:

 
I don't have the recommended horizontal surface to mount the solar panel on, but the trailer faces west and is in full sun in the afternoon, so I figured it'd be worth a shot to mount it flat on the front:



Looks like it's putting out plenty of juice:



As soon as the fuse block & my wire terminals come in, I'll get the winch wired up.

 
Still some tidying up to do once I make the main power cable to run from the circuit breaker to the fuse box, but the bones are there. I threw the jack on the circuit breaker as a test case to make sure everything was working as expected, and so far so good.



Most of that clutter is the solar panel wiring & charge controller, which'll get tidied up.
 
The electrics are *DONE*. FINALLY. Between drilling holes for grommets through the frame, making cables and figuring out where I want everything mounted, waiting for parts and cleaning up the 120v wiring, it took all my free time for like 3 days.

It's definitely not a professional job (because I'm definitely not a professional), but it's about probably the tidiest I could do without shortening the winch power cables. That'll probably happen eventually, but I want to wait for a few months and make sure nothing crops up as a reason to move something drastically.



I thought about shortening the wire from the 120v breaker box and running into the left side, but the length it was made it pretty ideal so that I wouldn't have a bunch of crossover points where that cable could chafe the unshielded 12v cables.

And tidied up the battery box:



The only things left are to hang a few more sections of E-Track tonight, put in another pair of big D-rings once those come in, and then it'll be ready for its first couple outings :D
 
I lied. I got sick of walking aLl ThE wAy down to the shop to replacing / charge tool batteries. Since I have a spare charger that only traveled with the tools to big events, I figured what the hell, why not?



Ok, NOW I'm done with the electrics for the time being (rlaugh)
 
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The electrics are *DONE*. FINALLY. Between drilling holes for grommets through the frame, making cables and figuring out where I want everything mounted, waiting for parts and cleaning up the 120v wiring, it took all my free time for like 3 days.

It's definitely not a professional job (because I'm definitely not a professional), but it's about probably the tidiest I could do without shortening the winch power cables. That'll probably happen eventually, but I want to wait for a few months and make sure nothing crops up as a reason to move something drastically.



I thought about shortening the wire from the 120v breaker box and running into the left side, but the length it was made it pretty ideal so that I wouldn't have a bunch of crossover points where that cable could chafe the unshielded 12v cables.

And tidied up the battery box:



The only things left are to hang a few more sections of E-Track tonight, put in another pair of big D-rings once those come in, and then it'll be ready for its first couple outings :D

Great work! My only suggestion would be to make sure the outlets are ground fault protected! You could see damp conditions and better safe than not! [emoji6][emoji1303]
 
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