Geometry

While the time these days is spent refining the design given physical realities,  much attention must be paid to the basic design.

In that vein, I am overdue in presenting the basic geometry and the thought process behind it.

Let us start with a basic representation of the trailer:

The horizontal line is 15" above the top edge of the trailer, while the vertical line is approximately 1/3 of the way back from the front (right.)

Next we need to spring two ellipses that share the axes shown above.  The first one uses the horizontal axis as its major axis, and the vertical as its minor.

The second ellipse uses the same major/minor axes, but the length of the major axis is much shorter while the minor is the same as the first ellipse.

Now the excess gets trimmed, and we see the basic profile of the trailer with the aft portion tracing the large ellipse, and the forward portion tracing the smaller.

The result is one continuous curve created from the combination of the two ellipses.  Cleaning up the drawing and adding a couple details results in this view:

Note that the window and door are balanced on either side of the vertical axis, and the horizontal axis will become a "waist line" in the aluminum cladding.

One Day Post-Equinox

The report on the Block Island Fishing Expedition is mixed.  There were fish to be seen, in fact three were beached, but two were 25" stripers where the lower limit is 28", and the third was a small bluefish.

Sadly, I beached nothing.

But, a great time was had by all, in spite of the constant 7-12 knot wind in the face.

Back to the teardrop:  Sean has been progressing on the electrical wiring.  Today I took a long, hard look at the design of the hatch edge where it meets the trailer body, and the attendant waterproofing.  We have a design, so now I can proceed to detail the galley, and we can begin to laminate the hatch frame edge and mating parts that get attached to the inside of the trailer sides.

Please stand by.

Progress in the Cabin

The focus in recent days has been on the two shelves that will be located on the galley partition inside the cabin, as well as continued work on the electrical system.

The last post showed the oak face frame assembled.  Below, the frame and two shelves are temporarily fit in place:

Note that the top shelf is so brightly illuminated because the ceiling panel in that area is not yet installed.

The next step was to sand everything and apply a first coat of polyurethane.

Today, after cutting the missing ceiling panel, we assembled the shelves.  Here is the finished product:

Left to do is fill in the nail holes and install oak plugs in the screw holes through the top rail (which is screwed into the main yoke overhead.)  The ceiling panel is in place on the top shelf, but not yet installed.  Eventually, the plan calls to close these shelves with roll-up tambours made from 1/4" thick white oak with beveled edges.  A fallback position would be to fabricate doors matching those on the electrical cavity.  In this case the bottom two doors would fold down with a 90 degree stop, and the top two doors would open up.

There will be no new posts for a few days; I leave tomorrow for a four-day fishing excursion on Block Island, RI.  If the past couple years are any indicator, we will thoroughly thrash the waters with all manner of lures and have no fish.  Fish or not, it will be a fulfilling diversion.

09/16

Recent progress has been a) making the electrical connections inside the electrical cavity, b) roughing in the galley area, and c) creating the rear cabin cabinet face frame.

Above is a recent state of the wiring progress.  The AC end of the Xantrex is connected to the AC breaker panel located in the left side door.

Above is a view of the galley area showing the counter and lower area structures in place; the entire area has been first-coated with polyurethane.  Below is the left galley area under the counter that will be devoted to the water tank, the pump and the sink.  A shelf above the water tank will provide storage.

 

 The mid-under-galley area is devoted to the full-extension drawer that holds the cooler and spare gas cylinders.

The right side area under the main counter will hold the stove.  The platform assures the  stove will fit front-to-back.  The area under the stove will hold various implements as required.

On the cabin inside rear will be two shelves, located high.  The face frame for these shelves has been created:

The middle horizontal will support a 3/4" birch shelf, while the bottom will support a 1/2" oak plywood shelf.  The fronts will be enclosed via tambours.

The top stringer will attach to the main yoke.  The two shelves will be attached back to the galley partition and trailer sides via cleats.

Progress 09/10

Over the past two days we've been progressing on two fronts:

1) Galley structure
2) Electrical cavity construction and connections

The progress to report on item 1 is that the structural components of the galley area are fitted, sanded and ready to install.  Before installation we need to assure that the galley wall itself is straight in the horizontal plane.  Once that is done we will glue up and install all the hatch structure components as seed below:

The hatch has three horizontal bays: Leftmost is the water tank, pump, filtration system and sink.  Center is the bay for the cooler tray and propane cylinder storage.  Rightmost is the (upper level) stove storage and a shallow drawer area beneath for utensils.

The left bay will contain the water tank and associated components.  The shelf shown will provide for extra storage.

The center bay will contain a full-extension drawer holding the Coleman cooler and propane storage rack.  At right will be slide-in storage for the folding Coleman propane stove and a shallow drawer beneath.

This shelf will not be permanently installed, allowing for eventual repurposing of the bay.

Below is the electrical cavity under construction:  

Shown below is the left side door installed and closed with the AC panel mounted and the DC panel in the background at right.

The small opening at the left side of the left door will contain the control panel for the Xantrex.

The door on the right side will contain the DC voltmeter/ammeter, the car radio and the speaker switches (cabin vs. hatch.)

September 8 Update

Progress is not what I would want, but is throttled by my own limitations.  I have arthritic knees, and have been getting another round of injections to help me along without the need for replacements.  I can only manage 3-4 hours per day on my feet, and this proves to be the limiting factor in the pace of progress.

Therefore, the completion date remains unknowable.

Over the past couple of days we have been tending to some details on the interior ceiling panel (the one remaining piece, which needed some nailers), fitting parts for the galley area, and preparing the electrical installation.

Below is a view of the current state of the galley; the vertical panels are intentionally cut long at this point, since they need to be notched around the cleats at the rear.

      
The left cavity will contain the 9 gallon water tank, the pressure-activated pump, the sink and the water filtration system.  Above the tank will be a storage shelf.  

The center bay will be home to a full-extension sliding drawer holding the Coleman cooler, behind which will be brackets for the one-pound gas cylinders for the stove.

The right bay will have a shelf mounted a few inches above the base which will serve as the floor of the stove storage bay.  The area beneath will be purposed as additional storage, perhaps as a drawer.

Following is a view of the Xantrex mount, including the AC fused disconnect and the DC breaker panel:

The assembly above will mount in the front of the electrical cavity as shown previously.

 

Progress on Two Fronts

In the past couple of days the electrical cavity and the doors covering it have received a coat of polyurethane.  The Xantrex mount has also been finalized.

Above are seen the DC panel and the Xantrex Converter mounted on the framework in the cabin front.  The oak cabinet face and other components have a first coat of polyurethane appled.

Above, the galley counter has been cut and rough fit.

 

Urethane Meets White Oak

Today the first coat of polyurethane was applied to the electrical cavity doors and to the cavity itself.  It was the first time in the project that urethane met oak, and it was quite rewarding.

We wanted to get at least a sealer coat on the inside of the cavity before any equipment installations were done, and on the doors (where we will want actual finish coats) before the installed panels are fitted.

Weather (plenty of rain) and intestinal distress have slowed other progress.  Please stay tuned.
    

Labor Day Progress

Progress lately has been slow but deliberate.  As the heart of the electrical system is in the electrical cavity, we have been carefully planning the installation of the components and the peripherals.

Below is a view of the mounting rails for the electrical components:

The rails will mount the AC fused disconnect, the Xantrex Charger/Controller, and the DC breaker panel.  We have placed the DC breaker panel inside the cavity to avoid needless strain to the 2/0 copper wires attached - repeated flexing can cause breaks.  Note that the verticals will connect to the installed cleat, conform to the curvature of the interior, and support the mounting rails.

The doors for the upper compartment will hold some critical components.  Below is the left side door:

Seen are the AC breaker panel / voltmeter on the right, and the opening for the Xantrex control panel on the left.

Here is the right side door:

At left is the DC voltmeter / ammeter.  On the right top is the (car) audio system, below which will be two switches - one for the inside speakers and one for the hatch speakers.


   

Electrical Cavity Doors and Equipment Mounts

After some delays, the doors for the electrical cavity are installed.  Seen below are one closed and one open.  The spaces below will have matching panels that are not hinged but rather just drop into place and latch securely.

The Ferrari America hardware used (from Connecticut River Lumber)  supports a 90 degree opening with support.  The left side door will have the AC panel mounted in it, as well as the control panel for the Xantrex converter.  The right side will have the DC meter panel mounted, in addition to the Kenwood car audio system.

Below the standoffs from the front are seen, to which will be mounted rails to carry the Xantrex and the AC fused disconnect panel, in addition to the DC circuit breaker panel.  We have decided to mount the latter in a relatively fixed position rather than on the drop-down door since it will have 2/0 wire connected to it, and heavy copper being repeatedly flexed will tend to break.

The next steps are to cut holes in the doors for the panels and other devices that will mount in them, and assemble and install the equipment mounting system that will use the above standoffs.