A new Teardrop Build

[Aguyfromohio]

So when we got started building it was winter. We used ½ inch cheap plywood to make a full size mockup of the galley and counter top. Recall we have a full size template so it was pretty easy to make exact shape sides. We built the upper cabinets first, then the countertops, before any walls or roofs. All inside while it was cold out.




made up the countertops. Used 1/2 inch marine plywood then glued on formica. Cut a full sheet into two countertops.
That's a pair of straight 2 x 4's guiding a trim router with a small straight bit

[Aguyfromohio]

Here’s our window air conditioner. We boxed in the back end at just the right places to capture only the outgoing hot exhaust air. That air box has an open bottom. We cut a vent hole in the galley floor and glued window screen across it. The air conditioner vents downwards blowing out that vent hole.

WARNING! Put a divider under the counter to prevent the air conditioner from pulling air down through the cooktop, and install a large intake louver for the air conditioner. The air conditioner can pull the stove flames down under the countertop and start a fire.

[Aguyfromohio]

We had work to do on the entry door and sides. The entry door was much trouble. It took lots of fussing with a sharp block plane to get the fit right, but it’s done. We resawed oak to make thin battens that we glued and screwed over the seams. Keeps out water; adds strength; and covers some ugly. We have battens across all the seams, vertical and horizontal on the roof and hatch.

[Aguyfromohio]

We are still knocking out the electrical connections and installing the galley, and the lights, and those last bits of trim....

But next step is the second trailer.
We have the frame with axles, wheels and finish floor all built and done for the second trailer. When we made the walls we made both sets, so the walls are ready to stand up.
My buddy wanted the wood siding you see above. We used 1/4 inch marine plywood, meranti, with Helmsman Spar Varnish polyurethane for all outside surfaces, and we used prefinished maple plywood for all inside surfaces.

However I prefer not to have wood siding . My exterior surfaces are built using 1/4 inch birch plywood as the exterior skins on the structural insulated panels, and we have a stack of prepainted aluminum skins to cut and add. All my exterior surface will be white metal like a cargo trailer.

[greygoos]

Nice build. Keep us posted

[Aguyfromohio]

The driver side, window and shore power receptacle

[Aguyfromohio]

The second trailer is the white one. It's coming along nicely.

[Aguyfromohio]

So here's the white one with the roof raised and the upper windows installed last weekend.
Notice the full grown man standing in the back corner, plenty of head room. That's my trailer building buddy Mike, he owns the wooden version.

[aggie79]

Room with a view!

I'll be the first to ask if you can show more details of your raised roof - assembly, weatherstripping, etc.

Thank you!

[tony.latham]

And door seal details, please.

Tony

[Aguyfromohio]

Room with a view!

I'll be the first to ask if you can show more details of your raised roof - assembly, weatherstripping, etc.

Thank you!

Thanks for the kind words.

Our design process started with a good looking idea in the CAD system which promptly collapsed into a hilarious series of panicked improvising.
But we got there.

The main roof is essentially just one more galley hatch. It has an extruded hurricane hinge at the front edge, and bulb seals down both sides.
Just like a galley hatch we have aluminum trim on the top edge of the walls as a sealing surface, with a small half inch lip sticking up on the inside wall.
That vertical lip will keep any rain leaks on the outside of the trailer. The top skin of the roof is an overhang out to the exterior skin, and the edge trim bulb seal attaches to that edge and rides with the roof. It seals against the top of the wall when closed. When it's closed the roof rests on that lip supported by the top skin all the way down the wall.

Typical galley hatches connect to a strong aft wall in the main cabin for good support and our galley hatch does that too.
For the main roof we did the same thing again. We built a strong front wall to attach the roof hinge. That cost us a few inches of interior space at the nose but gave us good structural support.

Our main roof panels ended up far heavier than they really need to be. So we need a power lift to keep that heavy roof under good control.
That bit was the biggest panic with the most improvising. When they were partially built we would push up the roofs by hand and hold it with a prop stick, but that is a genuine safety hazard that could kill someone if that heavy roof dropped onto someone's head. So we use a strong 12VDC actuator

The rear window is permanently attached to the main roof with a long piano hinge. Since it's tight under that overhang we aren't worried about rain getting in and didn't feel like buying a third hurricane hinge.
The rear window frame is skeletonized plywood and is part of the roof lift mechanism. The top end of our electric lift actuator pins to the center mullion about at the cross member and the bottom end pins to the floor against the rear wall. The actuator pushes up the window, and the window pushes up the roof. Mechanism design is a pain in the butt generally, and this one certainly was. All the angles change as the thing lifts, and it was maddening working out the fully closed position and the fully open position. We installed one inch wooden guide rails on the inside walls against the back window to capture and control it as it raises. More frustration working out those clearance gaps.

The side windows are loose parts that stow inside the cabin against the wall. Should we not bother with raising the roof, they are out of the way against the wall and we can pull out the sofa bed to sleep, or just sit in the pouring rain on the couch.

To raise the roof we push the button and up it goes. When it's at the top we can stand up, grab a window (they have two grab handles), and set them in place. Little clips hold them in place.
The side windows have bulb seals at the long vertical aft edges that crush against the back window edges. The back window has a stepped shape at the bottom that kicks out a half inch over the aft wall top so it sheds water properly. During this process the sides are wide open and the back window will funnel rain into the cabin, so we can't raise the roof in a rainstorm. We can live with that.

When the roof is closed the back window hangs tight against the back wall inside the cabin, captured in its rails, with just enough free room under it for the air conditioner to be open. The main roof latch is the actuator holding it closed. That thing is gear reducer plus lead screw that does not back drive or slip. It stays wherever it stops very strongly. There's a swarm of small details to make it all fit and work but that is the basic approach.

So we seem to have achieved a power lift roof with hard windows all around that is nicely usable either open or closed. It's a teardrop when towing and a standie when camped. Functionally equivalent to the many excellent expanding roof designs folks have built around here. We like the appearance of ours, and think the standing room is especially generous.

First trip out is Memorial Day weekend. Flight tests and sea trials always uncover problems, so we'll see what we find in actual use.

[Aguyfromohio]

And door seal details, please.

Tony

Tony you have keen eye. You can't see the main door seal because it isn't installed yet.
The door and door frame have a matching step profile, and we'll be sticking on small foam weather stripping from the home store on that surface.

[tony.latham]

Tony you have keen eye.

And I'm cutting door cores out. Or was until my router bushing headed south.

Tony

[Aguyfromohio]

So here we are pulling away from the house on our first trip. I did tow it once before, a couple miles to a certified scale to get a weight so I could get tags. But this was the first trip other than that one.
We went about 160 miles to camp with friends at their property.



The trailer towed very well, tracking straight with no wobble or fishtail. I admit to being a bit terrified of getting on the freeway the first time and rolling at high speed.
We had it as fast as 70 MPH and it was all OK. I set the cruise control on 65 and all was good. That little Mazda CX5 as a tow vehicle really rose to the challenge and did fine. But it is woefully under powered at about 180 hp, so on the freeway at every grade it shifted down to fourth gear, and on steeper freeway grades it went down to 3rd gear. Fuel economy was cut essentially in half, getting just 16 mpg overall. But the engine temp stayed cool and it pulled strongly at those higher RPMs as needed.

Here we are set up at camp.

[rmclarke]

Very nice build....would love to see more pictures...interior especially!