Expandable

[TJinPgh]

Also had a tiny trailer variation of something that could house at least 3 people if necessary.

Took various design cues from a number of different ideas around the board and came up with this. It's based on a 4x8 frame built out to 5 wide. Although, after drawing it up I really think it would work just as well on a 4 wide frame.






In it's "closed" form it's your typical 5x8 floor plan. Wide enough to sleep 2 adults lying from front to back.

The panel in the side, however, is a 3'hx6'l tip out.







This opens the floor up to a 6'x8' sleeping area in the 5 wide or a 6'x7' sleeping area in a 4 wide. I figured the tip out would be for your feet with sideways sleeping. But, you could still go either way. Whichever is more comfortable.

The quarter circles on the tip out are removable. This allows the trailer to be fully functional with the tip-out closed. The tip-out would be secured with cables or props in the open mode.

The red covering is marine vinyl. It's shown on both the roof and tip-out for weight reduction, but you could just as easily go with the roof material of your choice.

The questions I have at this point are storage and doors.

I like the idea of a rear door. This design certainly allows for that. Doing so, however, would limit my the available space for storage. Thoughts on where I could put cabinets with a rear door?

A more traditional side door allows the back 2 feet if the trailer to be used for storage.

In either case, the tip-out could be used as an "emergency exit" on that side, should the need arise.

Any thoughts on how much this might weigh in a 5 or 4 wide format?

The overall dimensions would be 4' high, 5' or 4' wide, and 8' long (plus the front "point."

[TJinPgh]

Little variation. Bit more of a teardrop. 4' wide.









Had a thought abut the roof.

1/4" Luan, from what I've read, weighs 20-25 lbs per 4x8 sheet. Is that about right? And, it still needs to be waterproofed in some manner.

I'd thought about going vinyl, but it would take a lot of slats to keep it from sagging.

So, instead of 1/4" ply, I thought about doing something different.

Home Depot sells 4x8 sheets of lattice made from a plastic resin. About .2mm thick. Extremely strong, very flexible and less than half the weight at 11 pounds.

Use it for the roof line, and cover it with snap on vinyl. In good weather the vinyl could be removed for ventilation.

[aggie79]

I think this is a good design exercise, but I do think that in the closed mode the roof of the tip out would block access to the teardrop door.

I have looked at designs for all types of expandable TDs and TTTs - lifting roof (Compact 3), lifting sidewalls and roof (Winter Warrior), slide-outs, tip-outs, etc. - and most difficult part of the design is to make it both weathertight in travel mode and in camping mode.

Please keep the design exercises coming. They help me think through the weatherseal issues.

[TJinPgh]

I think this is a good design exercise, but I do think that in the closed mode the roof of the tip out would block access to the teardrop door.

Tom,
Thanks for the reply.

I mentioned in the first post that the sides of the tip-out, the quarter-circles, are removable and the top of the tip out is just vinyl.

So, in closed mode all that would be there is the base of the tip-out (which is simply the side of the trailer) and perhaps some vinyl hanging down along the wall if I choose not to detach it.

[aggie79]

Oops. Sorry about that. You did say "marine vinyl". I missed that.

I had a design sketched (on paper - not in Sketchup unfortunately) that had two tip outs on opposite side. One was slightly smaller than the other and was on a slide the two would nest. I even thought I had the geometries, mechanics and seals worked out. The problem was, unlike your attractive design, my design was butt ugly in travel mode.

I like your creativity. Keep the designs coming.

[absolutsnwbrdr]

So, instead of 1/4" ply, I thought about doing something different.

Use it for the roof line, and cover it with snap on vinyl. In good weather the vinyl could be removed for ventilation.

I like where you're going with this

You may still have to add one or two cross pieces near the middle to help the structure stay rigid. That vinyl lattice will bend well, but it may have a tendency to sag in the middle too.

[TJinPgh]

I might.

If this actually gets built I suspect that it's something that will need to be determined on the fly.

I worked with those lattice panels when I closed in an area under my back porch.

They have a good bit of flex, but only in one direction at a time. My thinking was that, since there is an arc to the roof going along the length of the trailer, that it's unlikely that it would flex much going across the width.

Again, I can't say for certain. Would just have to try it and see how it goes.

In either case, adding a couple of cross pieces shouldn't be a major issue.

[LWW]

Looks like a good idea to me also. I agree the latice has weak point when on it's side. Since you're using marine vinly on the top how about a couple tubular crossmembers with a slight bow and stretch it tight across the top using snaps on the side to hold it. Sort of like a boat cover. Larry

[TJinPgh]

I think I still have some pieces of the lattice laying around here. I'll have to do some experimenting with it to see how strong it is in different configurations.

If we were discussing a flat roof, like I had in the first image, I'd agree that the latice wouldn't work. It would almost certainly dip in the middle somewhere.

Since the roof in the revised designed is a continuous arc, with no flat spots, I'm not sure the same problem exists.

Again, I'm not saying anybody is wrong. Just saying I'm not sure if it would work or not. Would have to run some tests on it to see. Some of some sort may well be necessary.

With respect to the idea of just running some tubular spars across, like on a boat cover. Certainly doable. And the vinyl would be snapped to the sides anyway.

My only concern there is whether or not it will sag between the crossmembers. Vinyl has a tendancy to stretch over time. Particularly when it gets warm, like on those hot summer days. The lattice provides the same benefit of a solid roof without the solid roof weight. No real place for the vinyl to sag to if it heats up and stretches a bit.

If we were just talking 1 or 2 crossmembers across the open area, I'm not sure that it wouldn't sag if it started to stretch.

Somebody here did a vinyl roof. Will need to look at that again and ask them how it held up through out temperature changes. Whether it needed to be snugged up somehow.

[mikeschn]

I started playing with something similar a while back, but never pursued it.





I agree with Aggie and the weather sealing issues, both when traveling and when camping. I know the prototype Winter Warrior did very well until I cut a hole in the front for the A/C. I won't do that again!

I also don't like the idea of canvas, which is what led me to the Winter Warrior in the first place. I do finally have the design optimized, and we'll build it in about a year or so. I hope to take what I learned from the foamie, and use the best of both worlds.

Mike...

[TJinPgh]

Mike,
That tip-out thread is actually what got me thinking about it to begin with.

I figured that since neither you nor anybody else posted a build thread on it that it never got built.

When I first started sketching it up, I started out with the angled box design that your sketch has. If I were going with something where the tip-out was "permanent," meaning that one would need to have it open to camp in it, I'd probably go with that.

Since my thought was to have it campable with or without it open, I thought the curved design was easier to work with. Fewer headaches with the vinyl.

Weatherproofing is certainly an issue. I think, in this case, it's more an issue with it open than closed. Closed, the principal should be about the same as any other side access panel. Simply a matter of making sure there's a good seal in place. And, while I didn't go into that much detail on these drawings, I do have some thoughts on that.

Sealing it up when it's open seems to be the bigger challenge, as whatever seals I use when closed probably won't work when it's open.

I do have some thoughts on that as well, and will post some pics on that when I get the time to draw them up.

[absolutsnwbrdr]

Somebody here did a vinyl roof. Will need to look at that again and ask them how it held up through out temperature changes. Whether it needed to be snugged up somehow.

Was great in the heat of the summer. I would get some smalll pools of water between my spars when it rained, but the vinyl would go right back to its original tension as soon as the water was off of it.

It even held up really well, even with 8" of snow (had to store it outside last winter for 4 months)



But I used 1x3 oak spars (about 12-14" apart). The spars do more than just support the vinyl though - they add a ton of structural strength to prevent the sides from racking.



That top lasted 2 seasons of extensive camping in all sorts of conditions - rain, snow, high winds. I sold that teardrop back in October, and the top was still in great condition.

By the way - it was a marine vinyl that I got at Jo-ann Fabrics. I'm getting the same stuff for my new build.

[TJinPgh]

Yeah,
after I typed that I went back and did a search for the one I'd seen with a vinyl roof and realized that yours was done that way as well.

The one I was looking at originally was the one Barb Bodemer did, with the black vinyl roof.



While there are obvious differences between the two of yours, there are similarities as well in that you both used the screen underneath the vinyl. Beyond being functional when the roof is rolled back I suspect it also helps prevent the vinyl from sagging a bit.

At any rate, like I said, I may well end up going that way. I just keep thinking about how little flex there seems to be across the 4' width compared to the 8' length of those resin lattice panels. And, it's even less when the panel is intentionally bowed.

While I don't think I have any full sheets left I do have some pieces laying around. I want to do some tests to see how much flex exists across the width when bowed along the length.

I admit that my desire to make it somewhat unique is at least partially driving my desire to see if it can be done without spars (or, at least with no more than one or two). But, I do realize that it needs to be structurally sound, as well. So, whatever works is the way to go.

I was in JoAnn's the other day looking at their vinyl. They had some nice stuff on their remnants rack in maroon for only $8 a yard. It's what prompted me to use that color in my sketch.

The fact that they only carry it in 54" wide rolls is also what prompted me to scale it back to a 4' wide design. I'd need to peace it to do a 5' wide or find another source.

In the grand scheme of things, going 5' isn't really necessary if I'm doing a tip-out. If 4' proves to be too snug for 2 people then we can always open it up and lay the other way.

Since the vinyl can be sourced locally for a good price, I'm also pondering the notion of making 2 different covers for it.

One that fits snug up against the lattice. Another that's a tad loose. It would allow me to put some form of insulation in between the vinyl and the lattice to help prolong the trailer's usability into the spring and fall a bit.

I'm curious about using the foiled windshield sun reflectors as a simple insulation for along that line.

[TJinPgh]

Did a couple of quick sketches on thoughts for the seals around the tip-out.

They're pretty crude but anyway..



The thought here is to have a flat rubber seal around the sides and bottom of the wall opening.

When the side panel is dropped and the tip-out sides are in place, the rubber would seal up against them.



This shows the tip-out from above. The rubber seal from the above sketch against the tip-out side. A seal on the side itself where it meets up with the inside wall.

And, finally, the vinyl cover itself...



The vinyl covers the entire flip out and attaches to the inside wall of the TD, the flip-out sides and underneath the front of the tip-out via snaps.

Not sure there'd be many other places where water would get in, but, if something stands out please point it out.

The big question I have at this point is how to secure the quarter-circles in place.

I would probably put a couple of tubular spars between them, which would help keep them in place and prevent the vinyl from sagging. Just need a way to secure it to the tip-out panel and the inside wall of the TD.

Had thought about using these to connect them to the inside of the TD. Easily removed...



Just need a way of connecting it to the base.

[TJinPgh]

So, still tweaking the design.

Looking at various styles, trying to decide what profile I like the best.

I keep coming back to this...



In some ways a clone of the Little Guy RT. Made by SignaTour campers out of FL. They have a number of variations on the reverse teardrop profile. Different door configurations. Different size trailers, etc.

So, anyway. Given that I keep coming back to that profile I figured I should give some more thought to it.

Came up with this... based on the same general idea of the models above, only more true to the Little Guy RT/SignaTour profile.











And, finally, I was able to put a galley in this one. Couldn't quite get that right in the plan above...



This profile, beyond the fact that I keep coming back to it, has a few advantage to it.

First, it seems to have more storage space to it. The extra cubic inches that the flat roofline gives seems to be the main reason for that.

Second, is the length. The 2nd design, by virtue of the front curve, was longer than 8', which meant I would need to extend the plywood. Doable, of course, but would require buying tools I don't currently have. Plus, it's a headache I really don't need for my first build.

I'll have enough challenges dealing with the tip-out.

I gave some consideration to a rear door. I like the general idea of it but could never really resolve the storage issue. Looking at the Little Guy RT and the SignaTour line, it would seem that they never really did either as none of the rear door models seem to have a lot of storage.

Not that this has a ton of it. Only so much you can do with a 4x8 footprint. But, even shallow cabinets (9" in the front & 13" in back) are better than no cabinets, I think.

Nor do they have a galley. Not that one is critical. None of my other designs had one. Still, they have their benefits. Plus, if this does get built, if I ever decide to sell it other people may be looking for one.