Excited to join this forum!

[publife]

We wanted to purchase an RV, but prices have been very high lately. Why not just build our own? My skills are limited, but this seems like a fun way to develop them.

So far, I know w have these requirements:

-air conditioning - legit AC, swamp coolers are worthless here
-fits a full size mattress - 52" x 73" for the trifold I have already
-dead simple setup - we'll want a galley, so we can just pull in, level out, and crack open a beer
-offgrid capable - I want solar and batteries, enough to be able to use the AC even when boondocking with no more than a few hours a day of generator use
-less than 3500lbs all loaded up, to give us the most TV options

I would really, really like to be able to build something we can stand up in. That's what keeps something like the Scamp on the table - being able to stand up is a big perk. I'm just not sure I can build something that tall safely. That's why I'm glad to be here - such an amazing resource!

[rjgimp]

Welcome to the asylum!

Your list of desires is totally doable. There are a number of standy and slouchie trailers that have been built successfully featured here on this site. Not sure how long you have been lurking but look at the Hall of Fame at the top of the home page for some good ideas and also look through the "build threads" topic for more detail on how those rigs went together.

Specifically I will suggest looking into building with rigid foam panels. There is even an entire section of the forum devoted to foam. This will help you easily attain your weight goal. Foam built trailers have proven to be incredibly strong and durable and provide ample insulation to maintain the results of A/C and heating efforts. You didn't identify where "here" is but many areas of the US and Canada have a decent selection of foam panels available year round.

[timhill28]

Welcome to the forums! If you got the time, skills and materials, this build will be easy. You can surely get some good leads here.

[publife]

Thank you guys for the welcome, as well as the vote of confidence!

I have been reading here (and solar forums) for quite awhile, but I still have years of threads to go through - I love learning about and seeing what others have dreamt into existence! I am in Florida, for what it's worth - we basically do not have a cold season, and for much of the year, it is hot and humid all day AND all night. Add that to being old and creaky (I now require a mattress and cool temps to sleep comfortably) and we need a trailer if we want to camp frequently.

I keep coming back to foamies - they show up in searches whenever talking about larger than average homebuilt trailers - but I haven't quite convinced myself that they're as strong as they obviously are. Right now, I'm leaning towards PMF over plywood sandwich panels, but that's partly because it plays to the 'cheap kids' playhouse' kind of skills that I have to my name. Unfortunately, on the ground, I can overbuild to my heart's content. When weight and motion are factors, I feel very out of my element.

Honestly, my problem right now is wondering if I should even tackle this. I saw a customizable trailer manufacturer that can build a 7'x14'x6'tall single axle enclosed trailer for around $3k base. That's big enough to mount four 400w solar panels on top!! I'm not sure how much extra it would be to have them beef up the design to accommodate the panels and the mini split components, plus any other upgrades I'd want like brakes, but it's an attractive option. Not actually aesthetically attractive, of course, but we couldn't care less what it looks like if it meets our needs well. If we do build, my plan is/was to build taller versions of the builds pictured in the second and fourth posts in this thread: http://tnttt.com/viewtopic.php?f=2&t=65778 . Part of me would be very interested in paying a good bit of money for a 7'x14' open trailer and building on that, but I'm not sure I'd be capable of building something both sturdy enough and light enough.

Anyway, I'm still enjoying soaking it all up! You guys have so much collective knowledge here!

[mary and bob]

As the owners of a vintage teardrop and two fiberglass campers, 13 and 17 foot, I would say you are better off with a Scamp or similar type camper.

[publife]

As the owners of a vintage teardrop and two fiberglass campers, 13 and 17 foot, I would say you are better off with a Scamp or similar type camper.

That's been my desire for a long time - and was my first inclination when we came to terms with the fact that we'd be getting a trailer, not a mobile home. Unfortunately, there are a few problems - they hold their value really, really well, and the market is high, so used units are nearly as expensive as new units. Even the 'big bed' is a little small - if I'm going to be towing a 16' trailer, I want a queen bed! If I could find a old but structurally sound egg reasonably priced somewhere to gut and rebuild, I'd do it in a heartbeat!

I think I've finally decided to build a smallish (5'x8'x6') proof of concept trailer first. It won't be capable of boondocking - the fridge and AC will only be moderately efficient 120vac units - but it'll be pretty cheap and pretty light. Hopefully I'll work out a lot of my 'I've never done this before!' issues on this build. Starting with a simple 12v solar setup might be a lot safer, too ;-) Plus, our estimation of base requirements might be off - we may discover that a bathroom isn't as easy to give up as we hoped, or that we really value the ability to cook inside, or something. Who knows, maybe we'll be incredibly happy with it and I'll just upgrade the electronic bits as I catch sales.

The big upside about this plan? I have enough cash in my 'frivolities' account to get started immediately - I won't have to dip into the RV fund until I start screwing things up! There's a community woodshop / makerspace near me that I'm going to tour next week, I'm hopeful we'll be able to work out a reasonable storage fee. I could technically work on it at a family member's home, but the height and the hassle has me leaning towards a community shop.

Excited!!

[rjgimp]

publife, where are you located? No need to be specific, just a state or even a region is fine. I promise I won't even tell anyone. Pinky swear!

[publife]

Haha, I'm in Florida - we rock the high temp / high humidity combo for most of the year.

[rjgimp]

Having foam/PMF pop up in a search is what brought me here too. I have read through dozens of build threads here as well as the BIG foamy thread which is now well over 400 pages and I am absolutely convinced of the strength, durability, and easy maintenance of a foamy build. If you haven't yet, read the Astroliner, Road Foamy, Canned Ham in Foam, and the Foamstream. These are all great builds with standing headroom and on a slightly larger scale than the typical 5 by 8 trailer kits.

Several years ago someone in this forum demonstrated the strength of PMF/foam by making a panel maybe the size of a small ironing board and actually stood on it as it was suspended off the ground. Another guy stood on the roof of his trailer. Up here in the far north we can get snow loads on trailers of a couple hundred pounds if we don't brush it off.

[publife]

So I've spent a few days looking at the builds you suggested, plus a few more - and then today I happened to click into the nontraditional 'pop up roof' thread. I stumbled onto Mike Young's build (viewtopic.php?f=50&t=40459) and the lightbulb went off. Building in a 'lift' on one end would simultaneously solve my headroom, tilting solar panels, and excessive height while towing concerns!

Still lots of other bits to consider, but I think I've hit on something truly viable.

I'm not sure this is kosher, but I'm going to use this thread as something of a idea journal. I can move elsewhere if there's a preferred place to log my thinking process as I dig through the forum and discover things I want to incorporate in my build.

[rjgimp]

publife,

There is a feature to the site you might find useful. You may have found it already. I didn't discover it for a couple weeks.

At the top of the home page there is a wide dark blue banner with the "home" button followed by "hall of fame" "design resources" etc, etc. Below that is a narrower, lighter blue banner. On the far right of that is the "login" button and the FAQ. On the far left is "user control panel", then the number of unread private messages you have in the system, followed by "view your posts". This is a listing of every topic you have commented in. If you stumble across a topic you find incredibly interesting and want to bookmark it for later hit the "reply" button and just throw in one of the smileys off to the right side and then that topic will forever show up in this list. If any new post is made the topic will move to the top of that list. That has turned into the thing I check first whenever I log in and there are at least a couple build threads I stumbled upon early on in my time here which I would love to find again but they continue to elude me because I never commented on them.

[troubleScottie]

To the original desire to run an AC unit via solar or batteries:

Although in theory it is possible, it is highly unlikely you will want to install that many batteries or that many solar panels. AC units are major power users. In addition, DC to AC inverters are low efficiency, so you have additional loses.

Your only real method is a generator or shore power.

Shore power can be very simple: basically an extension cord or more elaborate: distribution panel, fuses/circuit breakers, wiring, external 120VAC jack, etc.

Generators have some issues. One is noise. Two is weight. The small portables might not be big enough. As the generators get larger, they are harder to store or move or lift. Third is fuel. You need to bring and store fuel. An efficient gas generator might need to be refueled every 4-6 hours. Think refueling on a cold, rainy night. There are dual fuel kits for some generators to run off propane or gas. Not sure on what that burn rate is. But a bit easier.

[publife]

Well, the solar / battery setup is the part I'm fairly confident of. I have 16 280ah 3.2v cells coming in by slow boat right now - that's about 13kW of battery storage. Yes, it's almost 200lbs worth of batteries.

The AC unit I'm most interested in is a Mitsubishi 6k btu mini split - 33 SEER - less than 200 watts. Canvas siding for a lift might necessitate a larger unit, and there's a 9k btu unit that's 37 SEER that I might consider.

Anyway, even knowing that each inverter (takes two for split phase) wastes 50w each, that's still not obscene in terms of total power use. Being able to fit 1600watts on top would be awfully nice but requires a 14' roof. Fortunately, I'm not opposed to running a tank through the generator in the evening to top off the batteries.

With battery costs where they are (560ah 24v for less than $2000?) and inverter mini splits hitting 40+ seer, the future is here. Still pricey, but no longer a nonstarter.

[publife]

Decided to return to the simple proof of concept again - put together something quickly to confirm that the basic idea is sound:

*Back to a 5'x8' Northern Tool base
*Planning on a little over 6' tall inside.
*Planning on a few inches of overhang on the front end, giving me 96" x 56.5" inside
*Framing will be 18mm/.75in Okoume marine ply, doubled up as needed
*Skins will be either 3mm or 4mm Okoume, I can't decide - about fifty pounds difference
*I'm planning to use fiberglass cloth and epoxy, so I'm hoping I decide 3mm is enough
*Using 1.5" XPS foam
*Premade door and window - size of door and actual placement of vertical posts will be determined by the location of the tires
*6" thick mattress that folds up to be used as a couch. Will want to build in an elevated support because it's a really low couch otherwise
*Also want to build in some fold down tray tables for by the couch, and maybe a larger one for an additional work surface
*Roof is designed to support two 66" x 40" solar panels - making three inches of overhang on either side. Not sure if this is wise.
*Storing generator and gas cans on front, not sure that'll be enough to offset the fridge, AC, batteries, and kitchen equipment in the back
*Total weight of the box looks to be 400lbs-450lbs, depending on skin thickness, before PMF/fiberglass.

Hope I figured out the image thing! edit: I did not, heh. try two! edit again: yay! added a better angle for the walls layer too






This afternoon I'm going to go through all the crap I've bookmarked and list the products I'm looking at purchasing. I haven't really considered how much anything but the solar panels and batteries will weigh. I think it'll end up less than 1500lbs including trailer, but I'd like to get a rough estimate.


This is the short version, for when I wanted to attempt a popup lifting on one end to gain headroom and tilt the solar panels more optimally. Facebook folks seem to think my 6' design is a sail, and it would be foolish and unsafe to build something so tall on such a small trailer footprint. I'm not anxious to work out the extra issues that brings out, but I do want to build a safe trailer.

[publife]

So, the things I need to purchase, the options I'm leaning towards, and all that:

Trailer - Pretty sure I'm going with the Northern Tool 5'x8' (https://www.northerntool.com/shop/tools/product_200612541_200612541) though I would be having one customized locally if this wasn't my 'starter' build. ~300lbs, sells for $500 on the regular

Solar Panels - need two 60 cell (or, preferably, 120 half cell) panels, which measure about 66"x40" and weigh ~40lbs each, and produce 300-330watts. Just going to buy the best brand that I can get for a good price when I get to that phase. Not much point in buying and storing these yet. Two panels is ~85lbs, ~$500

Batteries - DIY LiFePo packs - I have cells on order from China, 280ah 3.2v. Will probably only put four or eight in this build, since I will be using an inefficient window AC and 110vac fridge and won't be able to boondock anyway. Eight cells is ~100lbs, ~$1000

BMS/Inverter/SCC - still haven't decided between trying out the LV2424 (https://www.mppsolar.com/v3/split-phase-lv-series/) all in one, or a good high end brand like Victron. Either way, looking at ~25lbs, $600-$1000

Generator - Cheapie 2000w Predator from Harbor Freight (https://www.harborfreight.com/2000-Watt-Super-Quiet-Inverter-Generator-62523.html) that should output about 6kwh per gallon to recharge the batteries, plus could run both the AC and fridge for about four hours on a gallon. Weighs ~50lbs, regular price ~$500

Air Conditioner - Really, any decent brand of 5000btu unit should work just fine here. I'll just watch the sales and get one when I see a good price. It'll weigh <40lbs, cost <$200

Refrigerator - This one is a little tough! I own a very efficient 12/24v chest fridge/freezer (https://www.amazon.com/gp/product/B076S52ZG2/) which would be ideal because I could theoretically just leave it in there and have it stay powered full time via solar, along with a couple of dehumidifiers and a camera/lights. Unfortunately, I use it for work so leaving it there isn't actually an option. Finding something with a small enough footprint but largish capacity is tough - and I want a bottom freezer if at all possible, so we can access the fridge part without folding up the bed. This Danby (https://www.amazon.com/gp/product/B08DYDXCZP/) is currently my leading contender - 18.5" wide, 19.5" deep, and 45" high. I found this one when I was thinking about making a poptop roof, but it still looks like my best bet even with more than 48" of height to work with. It weighs ~65lbs, ~$350

Mattress - I have a folding Milliard full size mattress (https://www.amazon.com/gp/product/B00W67PEY2/) already, and it'll work perfectly here. It folds into a half decent couch, if I can build in a way to elevate it a bit. Weighs ~35lbs, usually ~$200 but currently $225

Door - right now I like the combo screen door (http://store.mobilehomeadvantage.com/sku.cfm/sub_cat_id/467/ID/106/) that's on sale, but I'm not picky. Don't know the weight, but it'll probably cost $500

Window - I want a set of crank out windows, but all the shed window suppliers say they're out of stock. Might try Wiley windows, but will probably just buy inexpensive sliders if the crank windows don't become available.


There are also some other things I've put on my list, but may or may not end up getting:

1400w induction burner (https://www.amazon.com/gp/product/B07NP1TG29/) at <10lbs, ~$60
1400w Ninja Foodi (https://www.amazon.com/gp/product/B07K2LNDR4/) at ~25lbs, <$200
12v dehumidifier (https://www.amazon.com/gp/product/B000H0ZDD2/) two of these weigh a pound apiece and will cost ~$100
Induction Cookware with detachable handles (https://www.amazon.com/gp/product/B00HZVO9FY/) for both fire and 'stovetop' cooking. ~15lbs, $300
Cast Iron Charcoal Grill (https://www.amazon.com/Sungmor-Rectangle-Grilling-Outdoor-Decoration/dp/B07PCH7M2R/) is heavy and expensive, but I love it - <15lb, $100


Plus a zillion things like shelf brackets, lights, USB chargers, jerry can mounts, jerry cans (full of gas), screen room, folding table, camp chairs... I don't know if a 1500lb packed weight is going to be attainable! I'm already at >1300lbs just with the things I've actually put on a list!