Make Thee A Teardrop Trailer

I wrote in the last post of finishing the woodwork and electrical, buying aluminum and cutting a memory foam mattress.  I thought I was "Rounding Third", or something cheesy like that.  Little did I know from there it would take working through the rainest month ever in the history of the (dry?) mountain west to finish the camper, a marathon month at that.  Turns out it was a month worthy of building an Ark, or in this case, a teardrop trailer.  At the time of this writing and in the wake of the epic 2013 Colorado floods, I am currently isolated from the trailer, unable to access my parents' house due to road washout closures.  This project of course being a minor concern in aftermath of such a disaster, my camping trip has arrived less than a week away with no way to get the trailer out of the mountains.  What shall I do?

Well regardless of what happens next, here's how I got to this point.

The focus after last time was the 2' x 8' roll of coiled aluminum.  Bought from a semi-trailer supply shop as a roofing repair material, I found this aluminum to be the best compromise of quality and price.   As important, I needed 8'6" continuous to cover the sides, which this product provides.  As a 3003 alloy, this aluminum has a nice shiny mill finish that, with some care will look nice for a long time.

One of the first tricks was to figure out how to cut aluminum from a 23' continuous sheet.  To do this, we decided to roll the sheet out on my dad's porch and at .040 thickness, air tools- specifically the Husky Air Shear from Home Depot, were in order to do the cutting:

Before hanging and finish cutting any aluminum, we needed to prep the body of the trailer some.  For one, the plywood sides of the trailer hang down past the sides of the c-channel trailer frame, and as-is would be exposed to road spray and grime.  So, a search again at Home Depot found the perfect aluminum drip edge to cap the bottom of the plywood.   Applying with a silicone sealant and staples, the drip edge is a great fit:

With the drip edge in place, the full sheets of aluminum can be cut and hung.  Liberal use of hand clamps enabled temporary hanging of air sheared aluminum while Sharpie lines are drawn:

From there, manageable pieces of aluminum can be cut to precise size on the table:

Critical to the proper fit of the aluminum, was to allow about 1/16" gap at the edge of the metal for expansion and contraction due to differential expansion rates between the aluminum and wood.  Turned out that the Great Neck Three Piece Aviation Snip set provided a versatile set of hand snips for making right hand, left hand, and center snip cuts to finish the aluminum, all of which proved essential.  Using clamps and brads, the aluminum was temporaily hung.

We decided on a center-out, door-first fit strategy to minimize the likelihood of bulge and waves (or tin canning) in the aluminum.  A combination of drill, RotoZip, Dremel, and Sawzall were all used to cut the door openings.

With openings cut, doors and windows are hung.

Additionally, holes are drilled, wires run, and lights hung.

Along the way, at each of these openings in the exterior, a bead of silicon is applied along with strips or "boogers" of butyl caulk to limit water intrusion.  The same goes for the ceiling fan.  In this case, the fan is sealed with a trip layer- a sandwich of two layers of butyl caulk with a closed cell foam seal in the middle:

 The fans is finished with wiring connections and the installation of the trim ring on the inside:

Switching gears a bit- as part of the body prep., the stock wheel offset was compromised by adding 3/4" CPVC and 3/4" plywood to the sides of the trailer (all to stretch the interior width to 60" to accommodate a queen mattress, if you recall).  This created a potentially dangerous rub/interference situation for the tire sidewalls.  To get some of this back, wheel spacers were in order. At first, I considered hubcentric bolt-on billet spacer.  These tended to be expensive and a tricky fit.  A simpler, lower cost alternative came in using a slide-on over stud spacer.  The hang-up up with this approach was the need for a longer wheel stud to extend through the spacer.  After Northerl Tool confirmed they don't source replacement studs for my trailer, an exhaustive internet search found an appropriate replacement in the Kodiak Trailer 2" stud.  Using an unmounted bench vice (only a little redneck) to press out the old studs, and in with the new, the whole thing comes together perfectly:

Switching back to aluminum, with the doors, lights, and power receptacle installed, it was time to start installing edge trim.  Having two sheets of aluminum overlap in the middle of the trailer roof, a piece of flat insert trim with moulding from Frank Bear is used to cover the seam in sheets:

By the way, you've probably noticed the tarp in some of these pictures.  Have I mentioned the rainy theme of this part of the build?  More details coming...

Next up, the lower edge trim is installed, along with the fender, to finish the lower edge of the trailer.  The trim is notched to allow the brackets for the fender to lay flat:

Next up, edge trim is installed working from the front, over the top.  For this trim, it is pre-drill at 4" intervals.  Select holes are added to avoid conflicts with body screws and to secure screw trim ends.  Pilot holes are punched using the the trim, and then overdrilled in the sheet aluminum using a 1/4" bit to allow some movement in the sheet.  A bead of butyl caulk is pressed into the elbow of the trim for weather seal.

From here, the trailer side of the hurricane hinge is installed, with moulding.  This specialty hinge proves excellent weatherproofing:

After some delay, the kitchen door is skinned, with the hinge mounted at the top first:

The hinge is notched to provide a lip at the top.  The door has a hole drilled for the latch T-handle, and T-channel edge trim is added.

The kitchen door is hung by sliding the hinge on from the edge.  After, it awaits weather seal and final fit.

Along the way, running lights are installed.  This involved cutting conduit and using self tap screws with clamps to secure.

 Wires are run through the conduit with solder splice connections for the side marker light.

 

Brackets are drilled for the rear lights, before hanging.  Wiring for the rear lights is run through the trailer wall into kitchen before running down through the floor.

Whew...I'm out of breath.  So here's where it stands:

I'm so close I can taste it.  If I only can get there to finish it.  Whenever I do, I need to finish trim around the kitchen door opening, set door strike plates, and finish and seal the aluminum skin.  Until then, whenever that is....

Closin' In

...well, sort of.  Not closing in on anything in particular, but more to do with construction progress since the last post, and literally closing in the exterior of the trailer.  My last post reflected considerable progress building the cabinetry and skinning the front half of the trailer after almost a year hiatus working on the build.  With outdoor construction time running short for the second summer of the project, it was time to make a push to take advantage of the late season weather and get something done.

The next major construction challenge was to fabricate the rear galley door.  This would prove to be one of the most challenging and time consuming tasks of the project thus far.  I decided to frame the door using the glued and nailed 2"x2" stringers that were used to span side to side across the front of the trailer.  A critical difference this time though, is that the stingers need to be curved to follow the radius of the back of trailer.  Recalling back to the routing of the trailer walls, a jig was used to create a 48" radius curve on the back of the trailer.  This same radius (and jig) would be used to created the door stingers.  Working from a stack of 3/4" plywood spares from the earlier side wall construction, an afternoon of curved stringer routing lie ahead.

For each stinger, an inside and outside curve needed to be cut.  To ensure consistency, each plywood spare was screwed down temporarily to the saw table.  The outside of each stringer was cut using two router passes, one at half- and one at full depth.  The stringer inside cuts were accomplished by creating an inset pivot hole in the jig.  The jig was then unscrewed and reset set to the inset distance (about 1 3/4" shorter) before making the two inside passes.  Pretty simple, huh?  Scrub, rinse and repeat.

Not wanting to be guilty of building a wimpy trailer, I decided to err on the brick crap house side of things with construction.  Each side wall would be reinforced with a 1"x2" stringer, and then seven separate vertical 2"x2" stringers would span the width of the door.  Doing a little math on this, a total of 16 stringers would need to be cut (at four router passes each with a jig adjustment in the middle) for a total of 64 cuts, using about six total plywood spares.  [insert stupid joke here] If you act on this special TV offer, along with your Ginsu knives, we'll also throw in gluing, nailing, and chop sawing each stringer too.  But that's not all folks, in addition to all the curved stringers, straight header, footer, and mid-span stringers were needed as well.  [and second stupid joke here] By the time it was all said and done, we were ready to go into the hockey stick business.

Crappy infomercials/bad jokes aside, having trouble imagining what all this wood will be used for, or what it will look like when assembled?  OK, here's a sneak peek of it all put together, and following is how we got there:

My Dad made a good suggestion early in the fabrication of the galley door.  Rather than try to assemble and skin the door free from the trailer (and hope and pray that it fit when installed), we decided to build the door in place.  This would then allow us to skin it and cut it out after allowing the skin to bend and properly take the shape of the rear radius.  This approach seemed most likely to obtain the desire results in terms of build quality.

To accomplish this construction, we essentially needed to build the door from the outside-in.  After adding the side doubling 1"x2" stringer, we used scrap vinyl trim to create 1/4" door gap between the wall and the outside stringer.

 

To fix the door in place, a temporary 3" screw was then drilled from the exterior of the trailer through the side wall, the temporary spacer, and the outer stringer.

From there, straight headers and footers were added, and each vertical stringer was cut to precise length to fit between the header and footer, glued, and screwed at equal distances across the width of the door.

With all of the vertical stringers in place, three sets of horizontal mid-span spacers were cut to length, kreg'ed, glued, and screwed.

Voila!  A framed galley door!  Fast forward two months, borrow a neighbor's garage (more later), and the final tasks of closing in the trailer were at hand.  Remember the previous post on skinning the exterior?  Same applies here.  After cutting to length, starting at the bottom of the door (with a 1/4" spacer), a full sheet width of plywood was used to cover the door, bottom to top.  Add a box of screws, and some spar urethane, and here you are:

Gapping the top of the door at 3/8" to allow for the hurricane hinge to be installed later (coming soon), the final piece of exterior skin is cut to length and installed (without glue for now, to allow access to cabinetry:

The result...a completely skinned trailer.  Next steps?  Cut the door loose, install the door via a hurricane hinge (Santa brought some gifts, also to follow), and move construction back inside the trailer to finish the cabinets and possibly begin electrical wiring and insulation.

Until next time...

Where has a year gone?

So it's been almost a year since my last post.  Wow.  Around this time last year, I decided summer had been busy enough (and expensive enough) working on the trailer that I needed to pack it up for the winter and take a break for a while.  Fast forward about 9 months, and this summer got off to a slower start than I anticipated.  Two moves and a bunch more money spent, and I wasn't sure I was going to get off the ground this year.  I knew I had a bunch of work to do on the trailer with existing materials, I just needed the time to do it.  A three day weekend in August with Diane out of town in Cleveland presented just the opportunity.

I last left the trailer with the frame assembled, walls installed, door openings cut, and 2"x2" stringers spanning the walls.   After some discussion, deliberation, and napkin planning, my dad and I decided the next major construction work needed to be to begin construction on the pantry cabinetry in the back, and enclosing the whole thing with an exterior skin.

Ok, so a few more materials were in order.  A trip to Home Depot for some 5/8" and 1/4" plywood and a boatload of screws should do the trick for now.  Details below.

Focusing on the pantry cabinetry, we decided that construction would use 5/8" plywood to create the framing, joined to the walls with wood glue and a butt joint screwed through from the outside of the wall (no I'm not a woodworker, but I've stayed at a Holiday Inn!).  The choice of 5/8" was made as a compromise between thinner, lighter, and cheaper plywood, and something thick enough to support the butt joints without splitting or accidental screw punch throughs.  As part of this method, pilot holes and counter sinks were drilled for every screw.  At one point, this became a juggling act involving multiple drills and bits.

So, the question of where to begin arose next.  I liken our approach to this project (without blueprints) as either building a ship in a bottle, or designing a car around its ashtray.  That said, we dimensioned several things including mattress length and height, the sink opening, under cabinet space, and door clearance, and decided to begin from the counter top in the back.  Borrowed from some plans found online, the following illustrates the basic design concept for the kitchen space in the rear.

The design concept for the cabinet internals are depicted by the following:

The key elements shown here are a counter top (that will eventually contain a sink and stove), an above and below counter set of rear opening cabinets, and a set of above feet internal cabinets and electrical raceway for wiring, power strips, etc. 

Getting started on this design, with measuring and cutting, our first installed panel was the counter top.

From there, we moved panel by panel.  Next up, the cabinet face for the rear cabinet (and back of the lower cabinet):

And the shared back wall for both the rear and internal cabinet:

The internal cabinet spaces are becoming obvious:

And the interior cabinet and electrical raceway:

As you can see, many screws are used throughout.  A nearly complete cabinet framing looks like this:

Moving to the exterior skin, we decided on a Guatemalan 1/4" plywood.  This proved to be a nice balance between thick, sturdy construction, and the pliability needed to follow the 24" radius curve at the front of the trailer.  We also chose an "up and over" approach of fastening the plywood starting at the bottom of the front of the trailer, and working up and over to the back, bending the plywood progressively futher as we went.

With the plywood cut a bit extra wide, we started by clamping the plywood to the frame at the bottom.  We used 1" wood screws extensively throughout, screwing out from the center and across the stringers, and up the sides through the edge of the 3/4" walls.  Screws were spaced about every 4" with liberal use of wood glue throughout.  Along the way, we wet both sides of the plywood with a heavy sponge to aid in bending.

Along the way, extra stringers were added at the plywood seams to provide additional reinforcement and ensure the seams didn't "peel" up and show a hard edge.

A a router pass along the edges produced a nice, smooth finish where the plywood meets the wall.

A couple coats of spar urethane to seal it up and that's a wrap for now.  I'd say that's plenty of progress for one weekend.  When it was all said and done, my dad described the trailer as a "screw museum".  I guess it fits, huh?

Next up, finishing the cabinet framing, cutting door openings, and trimming out doors. Oh, and beginning to tackle the nightmare back door.

With winter already around the corner again, my attention has turned to securing a working space that will allow me to continue to work on the trailer through the snowy season.  My dad has an angle on a neighbor's garage.  Details to follow...