Thrifty Alternatives ..Building Foam Campers

[eaglesdare]

I just finished the Painted Caves. So disappointed with the way this series ended. Especially for the years and years and years of waiting for the books to be finished. I started reading them in my mid twenties, and just now finished the last one (mid 50's). So glad it is over!

[Jack B.]

I know how you feel about the Cave Bear series. I gave up middle of the third book back in the early 90s. Then when the last one came out I thought I owed to myself to start over and give them another go. I love the premiss and you do get a lot of accurate historic info and all, but after the first book the story seemed to start playing second fiddle to the author's pent up romantic desires or something. Perhaps Jean should have tried building a foamy to work out some frustrations.

And back on topic - conjecture:

Since if one were to stay in a wilderness sites for weeks at a time standing room would be pretty nice to have even in a smallish trailer. I know the sort of monocoque structural features of stretching fabric over the foam shape makes it much stronger than the materials would suggest. What I'm wondering is, if you build a pop-up structure based on the simplest concept of an upturned box nested in and under an inverted box who's sides fit over the inner box in transit, how do you go about maintaining that fairly high structural strength when the top is up? Without the continuous surface "tension" of the painted/glued covering from floor-to-floor-over-the-top on all sides it seems the integrity of the build would be weakened quite a bit. And it goes against the grain (pardon the pun) to just start throwing in 2"X4" braces to beef things up.

If foam construction is going to ever get into the "Airstream mainstream" issues such as this will come up. If you build it big it'll be strong. If you build it small it will be strong. But if you want to combine small towing and big parking things like this needs to be considered, hmmm?

Jack

[Mary C]

Jack have you read about the foam ling Bonnie is building ? I believe that is an experiment you can follow to get your answer. It will probably answer some more of the questions you haven't asked too.

Mary C.

[bonnie]

And back on topic - conjecture:

Since if one were to stay in a wilderness sites for weeks at a time standing room would be pretty nice to have even in a smallish trailer. I know the sort of monocoque structural features of stretching fabric over the foam shape makes it much stronger than the materials would suggest. What I'm wondering is, if you build a pop-up structure based on the simplest concept of an upturned box nested in and under an inverted box who's sides fit over the inner box in transit, how do you go about maintaining that fairly high structural strength when the top is up? Without the continuous surface "tension" of the painted/glued covering from floor-to-floor-over-the-top on all sides it seems the integrity of the build would be weakened quite a bit. And it goes against the grain (pardon the pun) to just start throwing in 2"X4" braces to beef things up.Jack

'Tis what BUB is. I am looking at using 1" walls on the top, which will be a pivoting pop up. 1x2 bracing along the perimeter to firm things up. The original BUB lid's sides flexed quite a bit. Of course it wasn't fully fiberglassed, so I don't know if it would have needed any bracing. My lift is designed and most of the parts bought. It will allow the pivot to rise and roll back the 6" or so it needs to be fully upright. As a precaution, I am designing a second brace system close to the pivot point. I don't think it's really needed. Call it over designing. Proof is in the pudding, so they say.

[razzer]

Say Jack , I've seen a builder who makes vardo style trailers with traditional materials where the top just fits over the bottom . Basically a right-side up box with an upside down box over it . It seems like a foam trailer would be easy to do this with .As I remember they have great website " Canadians ? " . But check out this thread it might be the same people . http://tnttt.com/viewtopic.php?p=93273

[Jack B.]

Now razzer, that's what I'm talking about. As I ponder the thing that seems the most troubling is the wall thickness using foam sheets. You want 2" for strength and longevity but then you get into door design problems. Looks like he did a pretty good job with his though using standard materials.

Jack

[razzer]

Now I haven't even built my first one but this seems like you might need at least a little bit of a frame for the pulleys to hook to .

[Bogo]

Now I haven't even built my first one but this seems like you might need at least a little bit of a frame for the pulleys to hook to .

As long as the load is spread over a large enough area, no. For most builders, a light frame should do. It would be easiest to have some framing to control twist loads on the pulleys.

When designing a lifting top, think carefully about the seals in both the up and down positions. When down it will be subjected to 70+MPH winds while driving. The seals will need to be good to keep the dust out. In my designs I'm using some cam latches to hold the top down, and up. They will snug the top and bottom together to compress the seals. (Pull-Action Toggle Clamps: http://www.mcmaster.com/#latching-clamps/=m0zmr1) My design does require the edge of the top and bottom to be much stronger than the foam it's self is, but then I'd using SIPs with Filon skins and border frames.

[Bogo]

Are you volunteering for that job Bogo ??? .. easy to suggest , difficult to do .... We could use a talented individual such as yourself in the organization process..

I wish I had the time. I KNOW how much time it can take. The farm is eating up most of the day time, which is unusual for winter. Evenings are currently spent farm planning or writing code to control the latest sculpture. As I write this it's slowly creating patterns of light on the wall. I haven't made a static sculpture since college. Bloody sculpture class teacher forced me to make a few fixed static ones. I don't know why I took that class. I didn't learn anything, and taught the prof allot in the process. Maybe it was for the easy A+.

Anyways, crowd source the rewrite. Pick ONE area each week, somebody write up a start on it or cut-n-paste the original discussion parts out of the big thread, discuss it to death, revise, lather, rinse, repeat until satisfied. Just like the initial ISCABBS Policy was written. I just don't have consistent time to wrangle something like that right now. Even back then I had a secretary and some assistants do the day to day work. I just wrangled them, guided the process and kept everybody on track. Still took an hour or two a day keeping up with the online discussions. The secretary and assistants handled all the rewrites, etc..

[GPW]

It is a Big job !!!

[eaglesdare]

It is a Big job !!!

ditto!

[Mary C]

I think that newbies should read the whole thrifty thread then they would get the understanding that everyone talked about foamies and tried and experimenting and such and no one took the foamie idea lightly, sure there is a lot of other stuff but we passed the time while experiments were done and the ideas were tried. I believe this is the proving ground and the passion. How else can new and inventive ideas be born? The wood and aluminum ideas were proven in the 1940s this is now the 2012 and 2013, ideas and the foam ideas have to be proven so ..........If you are new to the Idea then before one jumps in,the history needs to be known, and understanding that it is new and with time 5 to 10 years then a whole group of people will have proved the longevity and durability and will be accepted as normal (on the other part of the forum site?) There are many people who are completely happy with their foamie and will build another one. Thus we learn. No one has entitlement because it is just an opportunity to try something different and as GPW has said "the idea is for building thrifty", "thinking out of the box" and "it was invented for thrifty" and "build it like you want too". there is no definition about what is thrifty for you and no rules on how you must build or what products. We discuss ideas and report of our experiment on this thread. So...... read this thread and the ones on the builds and the ones on canvas, glue etc.

It is undoubtedly an enormous task to decide the most significant parts of this thread and the parts that are "need to be read" Louella has done great job, If you think foamies is a novel idea then, after reading build your own, use what you have or try different things. This is where we share our building experience, discuss and decide what works best and experiment. Nothing is written in stone but it might be to your advantage to read what others have done and tried before you waste your time, money and efforts to replicate the same experiments.

My 2 cents worth!!

Mary C.

[ghcoe]

And being that we now have 365 pages, you only have to read one page a day to finish by this time next year........

[Jack B.]

Yeah. Those of you with self control might do one page a day. When I read it all, I did it in three long nights. Along with getting more good ideas than I can ever follow up on, I now know more about ponies, horses, puppies, dogs and windy bridges (not to mention frozen turkeys) than I would have ever thought possible. And don't even get me started on frogs muddy campgrounds. After going through my reading up on sailboat building decades I at least had a grasp of the ballast concepts brought up here.

I'm in agreement that there should be a unified place to look for "just the facts Ma'm" on the building and deign aspects covered here. We're a long way from definitive yet but there is a lot of useful musings and speculation buried in here. 'Bout time for a manual to come rising out of this olio of ideas, clean and concise. As Mother Earth News was always fond of saying - "From them that's doing."

Jack

[Bogo]

(not to mention frozen turkeys)

Yeah, when using the bird canon for testing, don't use frozen turkeys. Thaw them first.