Planning a Mostly-Foamy V-Nose Maybe-Stoopy

[celadon]

Greetings, foamlings!

This thread is where I am hoping to work out a plan for building my small travel trailer. I am aiming for a garageable standy (probably made stoopy by the garage door clearance, but hopefully helped by the fact that the tallest person camping in it is 5'8") with a full-size mattress crosswise in the back and a small kitchen/storage area in a v-nose on the front. I am going to try to avoid the complexity of a drop floor or a pop-up roof. I've just begun constructing a 1:6 scale model and will post about that as I work through it.

I have the NT Ironton 5x8 trailer and a flexiride axle for it. The axle will hopefully help me gain some headroom since I can drop the ride angle on it. I also already have a fridge: an Engel MT-45 that I am planning the kitchen around.

My tow vehicle is the RAV4 in my avatar. 3500lb towing capacity.

I am currently considering:

A "sandwich" wall construction: thin plywood inside, 2 x 3/4 foam, then PMF on the outside. The 2 layers of foam will be easier to procure and allow me to easily insert 1-by wood into the inner layer where I need it and use a sort of rabbet joint at the edges.

A gently curved roof constructed mostly in the common inside-out method: inner skin, spars with foam between, but then a thin (1/2"?) sheet of foam and PMF over the top as the outer skin.

A tongue extension to provide a bit more space between the v-nose and my tow vehicle.

Robust solar power for boondocking--probably flexible panels on the roof. DC power only for the trailer interior.

I'd love to hear your thoughts! Now to figure out how to do pictures...

[celadon]

Here's the rough floor plan for the trailer. Dimensions are not final, but the scale is 1 square = 3 inches.

Full size bed in the rear, with 6 inches of space behind it because I like to dangle a hand or foot off the bed sometimes. I'll be in the back because I rarely get up overnight, and won't mind climbing over my husband if I do have to get up.

The fridge will be all the way up in the front of the v-nose, with space to place our camp stove to the left of that. To the right, I'm thinking we'll place coats and shoes there, like a tiny mud room.

The trailer frame itself is shown with the kind of teal-ish line. The trailer body will likely overhang the frame at least a little on all sides.

[celadon]

My mock up of the trailer frame itself. Including highly realistic tires!


Added a floor to the trailer, so you can see the footprint. Also added a bit of a tongue extension.


I cut and fit together some cardboard to represent the bed platform frame. I'll glue it in place but for right now it's just set on top of the floor. The outer sides will frame the wheel wells. Currently thinking I'll construct this out of 3/4 inch plywood. It'll be heavy, but we're reasonably chonky people and we have 120 lbs of dog that might join us on occasion. Doors on the rear will provide access to the rear storage for things like camp chairs and whatnot. The cutouts under the frame are to provide a bit more floor space for our dogs to spread out in the front, and to allow long things to be placed in the rear.

[John61CT]

Forget "flex" panels, for longevity go framed, dimensioned to fill the roof.

Might want to go flat (flatter) roof to accommodate.

[twisted lines]

3/4" is a wish here.

[celadon]

Forget "flex" panels, for longevity go framed, dimensioned to fill the roof.
Might want to go flat (flatter) roof to accommodate.

I've been thinking the flex ones will be worthwhile for me so that I don't lose any height to the panels, and so that I can keep the curved roof for two reasons: strength and the ability to put a roof vent fan above the bed where the roofline is lower, again to avoid adding height.

3/4" is a wish here.

You mean you can't get 3/4"... foam?

Thanks for the input! Keep it coming.

[John61CT]

The flex will not last even a decent fraction as long as framed.

If you are OK replacing after say 3 years fine, but realise you are also paying much higher $/Watt and getting lower efficiency per sq ft.

[twisted lines]

3/4" is a wish here.

You mean you can't get 3/4"... foam?

Correct but may try cutting to it soon.
I think it's an area thing, but I am no where close to you. (Some can)

[celadon]

3/4" is a wish here.

You mean you can't get 3/4"... foam?

Correct but may try cutting to it soon.
I think it's an area thing, but I am no where close to you. (Some can)

Gotcha. I have seen 1/4, 1/2, 3/4, 1, 1.5 and 2 here. But mostly the smaller ones in any kind of quantity. Guess I lucked out!

The flex will not last even a decent fraction as long as framed.

If you are OK replacing after say 3 years fine, but realise you are also paying much higher $/Watt and getting lower efficiency per sq ft.

Fair enough. In terms of cost, I'd be paying my $ for more than just watts--it'd be also for the benefits of low profile and curvature.

[celadon]

Did some work on the trailer model today. Glued some 1/4 foam sheets together on their flat sides so I can make wider, more sturdy "tires," but no pics cause it has to dry before I can cut them out. Also started gluing some cardstock to one side of foam panels so I can make sides out of them. In this case the cardstock represents the thin plywood I am planning to use to finish the inside. Mocking up some PMF on the outside is next for those.

Also put together the first 3d rendition of the profile in cardstock. I think I'm pretty happy with how it turned out. High point is 6 feet (scaled to inches in this case) and low on the front and back are both 4. Might be a bit close on the back end in terms of clearance above the bed. The bed platform will be 18 inches off the floor, so with a mattress that's just 2 feet of space above. But the last 6 inches of the back are storage and the roof ascends quickly there... gonna have to think about that some more.

Here's what you're here for:

[JasenC]

You've got an interesting design as well, and going all scale model.

I like the floor plan and I think your shell is going to look awesome.

[celadon]

You've got an interesting design as well, and going all scale model.

I like the floor plan and I think your shell is going to look awesome.

Thanks, Jasen! My brain works better with the tangible models than the computer drawings, I've found.

[GPW]

Very Cool !!! Like a big slice of cheese … Should be very aerodynamic …

[celadon]

Very Cool !!! Like a big slice of cheese … Should be very aerodynamic …

Thank you! Mayhap the choice of cardstock color for that mockup will spawn some kind of a cheesy nickname for the build. Vel-vee-ter?

My hope is that the leading edge of the trailer will fall below the roofline of the tow vehicle with this design. I'm not fancy enough to try to pin down ideal aerodynamics but I figured not pulling a parachute would be helpful.

[celadon]

Hello again! I am back after about a year in which life and other things happened... back to the trailer!

I deleted all my photos accidentally on my return, so I had to edit them all back in

Anyway, I was originally going to mock up actual materials on my scale foam model, but I don't think I am going to do that now. I did some work on it just with foam currently held together with painters tape, so I can mess around with things. Here's what we have so far!


Side profile with the door cut out. The down low window is for ventilation and for our dogs to keep watch for any shenanigans.


Rear view. Cargo compartment door to access the rear storage. Leaning toward doing two or three smaller doors instead of one larger door, but not committed yet.


Overhead view. You can see the divider structure and I've started on laying out cabinets and whatnot. The lil fridge is a 3d printed model of the fridge we have already.

I would love to add a small window in the kitchen area to crack for ventilation in the event of indoor cooking. Ideally it'd be on the diagonal wall. Is this a terrible idea? Like, for water intrusion or maybe glass damage reasons? I sometimes see windows on the front of things... but not often.

I already have a 32x18 fixed window that I'd like to incorporate somewhere, and I would also like to get an exit window on the back or back-left side. These and any other windows are TBD with regards to placement.