Teardrops n Tiny Travel Trailers

I started a thread over a year ago showing all my foam testing and boat building. This thread will just be for the Mercury camper build. You can skip to the end here https://www.facebook.com/media/set/?set ... 91420c25be
I started with a free pop up. It was the perfect donor, infested with mice, repaired, then infested again, the PO just needed it gone.

I then stripped it down

and found a bunch of goodies.

leaving me with a nice frame

I would recommend if you are offered a choice of pop ups, go with the coleman, they seem to have the least amount of wood in the build, making it much easier to get rid of the scrapped remains. I got about $30 at the scrap yard for the steel and aluminum removed from the pop up. I scrapped a starcraft a few years ago, and was left with quite a bit more wood to burn.

I wanted a longer wheel base than the current frame had, so I removed the axle spring bolts. I made the slipper end into the forward shackel, then fabricated a new slipper shackel. This lowered the frame a bit over an inch, fully loaded on our trip it did not bottom out on the frame.



then used sections removed from the starcraft frame when I made it 5' wide to fill the holes in the Coleman frame left by the old axle, as well as the hole where the step was. I also made the rear bumper into part of the frame. And cut away the frame blocking the wheels in their new location.


In the end I didn't use the plastic wheel wells, they weren't tall enough with the lowered frame height.

this left me with a nice foundation to lay out my new floor.
three sheets of ply rabeted and glued together.

the brown color is deck sealer I got from the oops rack at the depot
I then trimmed the angles of the front, then used the paint eater to remove a few inches of sealer so I would have a solid wood area to glue the PMF underwrap to. The paint eater is the best paint removal tool ever, it will remove the paint, or fiberglass and epoxy, but still leave pencil lines looking like they were never painted over.

I then flipped the floor over to it's final position. the unpainted lines were from me painting in between the frame rails.

I had to put up my tear walls myself, I started by drilling through the floor, then hammering nails back up through the holes. These nails keep the foam in place while gluing. They may add more strength to the build, but a minor amount really.

once I had the minimum dimension needed for a forward cabin door, I set the front wall location.

since foam doesn't rot, I could put holes in it anywhere I wanted, here I'm using the drywall knife to make a hole through the wall to locate the main door hole.

since it was very hot, I had to figure out how to work alone, here I'm using cheap HF clamps to help me line up the cut for the front wall.

this allowed my to dryfit my panels tightly for perfect joints. These joints will be seeing the greatest air load, and also be what I push against when moving the tear by hand.

as always the best work stand is the tear deck

those posts are to give me something solid to latch the front cabin doors to.

using straps to hold the walls tight to the forward wall.

bamboo skewers holding everything just right as the glue cures

cutting the door frame out

keep that bottom edge at an angle to keep the water out.

door

front cabin door, the vertical post is to give me a hinge mounting point, and to reinforce the most vulnerable point on the tear.

I love working in foam! in less than one day I had good start on the front end, now for my galley brainstorm. a design that I have never seen before.

This picture reveals the secret of the whole two story camper idea. A wall dividing the front into a forward cabin and the main cabin. While the front door is narrow, it is just fine for me to squeeze through, and is plenty of width for my kids. This will be the space for my son to sleep in, and storage for the upper cabin walls

Now I was back to the galley, this is the part that gave my project a new name. I had been using the name Skyline, but once this part was complete, I had to give it a new name. The galley lid design is different, and gives the whole tear a radical look, shut or open.

here I'm using my butterfly scarph joint to make the foam longer, I need the length for my wingback galley lid.

for the fun of it, I threw my foam kayak Sawfish, on the roof. I was planning on making the sidewalls 6" taller, but after putting a boat on the roof, I realized I didn't want any more height to have to deal with. Sawfish is a 23 lb boat, but I don't want to have to deal with ladders to put boats on it, or to deal with the sidewalls of the upper cabin any higher.
Full details on sawfish here, two time prize winner on instructables.com
https://www.facebook.com/media/set/?set ... 2a9935e7a1

with the sidewalls lengthened I could cut the galley lid walls to shape.

while these look like major tailfins, they are really the sides of the galley lid.
The normal tear curved hatch limits storage in the galley compared to a flat back end, but does give an overhead hatch for rain or sun shelter. The Mercury hatch gives more space for storage than a normal tear offers.
The Mercury hatch has no upward facing seams, other than the galley hinge itself, the easiest one to seal. Storm warning, my modified Benroy design is falling apart due to sealing issues with the galley hatch.
I have seen wind tunnel data that shows that the air flow does not follow the curved hatch of a teardrop much past the hinge point anyway, so this rear end treatment won't be a big drag.
A flat galley hatch doesn't lift high enough to clear your head when you get in close to the galley, unless the roof line is high to begin with.
The Mercury galley lid slopes the opposite way from the hinge to give the extra height needed for headroom when open.

to ensure the galley walls were vertical while the spars were glued in, I used the off cuts from the roof to brace.

tape was used to hold the GG in while it cured

once the spars cured, I braced the galley hatch wall in place

I needed a double spar for the galley hinge, one spar on the tear, one on the hatch, I used a plastic shopping bag to keep them from being glued together.

once again I'm using a live plastic hinge, it has proven to be very tough on my first tear.

the hatch wall was glued on and taped to cure.

unlike the rest of the tear, the galley hatch roof section will not be walked on, I made it of 1/4" plywood, and glued it down, the aft side of the live plastic hinge was nailed in between the roof and the galley spar. Since the live plastic hinge is 5' wide and the tear 6', I used some inner tube to cover the gap at the ends.

Then I cut the galley hatch loose from the tear.

to ensure that the back of the tear stays square, I cut away enough foam to frame the edges with 1x wood.

to ensure that the frame was well anchored to the foam, I drilled holes into the foam, then used the PLp gun to fill them, the board is glued to the foam with PLp and the glue in the holes swells as it cures acting like bolts deep into the foam.

to allow the galley lid roof to hinge past 90 degrees, I routed the edge of the roof

The galley opening frame, has a lip glued around the inside, this lip will catch and divert any water that gets into the galley hatch seam

As the galley hatch is closed the last few inches, the galley hatch spar slides down onto the ledge created by the top lip. The ledge is supported by the vertical members of the lip.

What you have there, sir, is a pointy bustle. Very much the same design rationale for the high rounded bustle on TPCE. Another benefit is it will allow you to bring the galley counter out very close to the rear edge of the floor, or in your case maybe even further; no hatch rib conflicts with counter or cabinets, no shin knockers and less back bending over to reach.

Yeah I don't have any upward facing seams this way, eliminating the most possible leak.
I plan on a galley shelf extension that hinges up to retain item's on the top shelf for travel. The galley prop rods are the retainer for the bottom shelf as their hinges are bolted to the latch plates.

Unlike the rest of my doors, this door is not shaped, just a big rectangle. To support the roof, there is a wood frame all the way around this opening.

There is a wood reinforcement on the inside of the blank, it extends on the front so there is a lip on the front of the door, it locks in behind the corner post to secure the front of the door in place.
the rear of the door has a couple screws tacked into it for now, once I get it worked out, the rear of the door will have two latches to hold it shut, it will only be open for stowing and deploying the upper walls.

this door was sealed over with PMF for now

This will allow the second story walls to be stored and travel in the front room, then come out and be assembled on the roof.

I knew the hatch profile would be different, I expect it to be polarizing, some hating, some liking. I care more about function than form, and this hatch is all about that. I designed the whole trailer in my head, the fine details were normally worked out on the fly, though some went through more than one mental revision until I like what I saw.
I propped the cut off section of galley in place to see what I had imagined

exactly as planned.
I knew I wanted at flat rear on the tear, and at 5' high, even my wife would have chances of bumping her head on the open hatch when opened, if it hinged overhead. by extending the roof line aft of the hinge, the under side of the hatch would be pushed upward when open, just like the forward hinge on a normal tear caused the curved lid to open high. Most of all I wanted a hatch to stand under for rain and sun protection.
I installed the tear side of the live plastic hinge so it is screwed to the vertical face of the aft most spar. I countersunk the screws into the aluminum strip that retains the hinge.

closed profile

with a 6' wide galley, the shelf will see plenty of weight, to give it a good support, I drilled into the foam again,

I then filled the holes with PLp

and glued vertical strips of 1/4" plywood to the walls using the "glue bolt" method, there are two strips on each end, and two near the center of the galley
1/4" ply is very strong in compression, I remember seeing the numbers somewhere and being very impressed. This galley shelf would easily sleep an adult with no issues.

more framing was installed to support the galley shelf

with the ends of the aft support beam pocketed into the vertical members for strength

the fore and aft supports in the center were also notched into place, making each joint stronger, everything was glued with PLp

then the shelf was glued and nailed in place.

I created and used these hatch props on my last tear. however due to how ugly they and the tear were I never really showed them off. This time I did it nicely enough to show.
I start with a small swivel caster, just wide enough to fit the support rod. I could have made it easier if I bought a caster with a bolted axle, but those cost more. Instead I had to drill the axle out as the ends were crimped, then come up with a new axle.

some locking pins replaced the axle nicely

I screwed the caster bases to a plywood plate that also anchors the galley hatch latch through bolts.
To hold the hatch open, I installed two large drywall screws, the rods drop over the screws to hold the hatch open.

to keep the rods from being lifted off by a breeze I drilled the ends of the rods and put a lock pin in. With the pin installed the rod cannot be lifted over the screw head.

The prop rods are swung in and clipped into pole clips mounted near the center of the galley hatch, the security pins are then clipped over the ears of the pole clips for safe travel. The two rods act as a retainer for heavy items on the lower galley shelf.

in use we did hit our heads on the rods a few times, however I plan on an extended galley shelf that hinges upwards for storage, this will keep us out far enough to avoid the support rods.