| Mon
18 Feb
Despite the lack of activity on the web site there
has been a lot happening, a thousand small and mostly
uninteresting jobs. I've added stays to most of the
shutters, fire-proof lining around the cooker, insulation
around the oven etc.
We've
also been working on the roof for the past day or
so. We're using all the solar panels from Wothahellizat
1 and it's a pretty tight fit.
In
keeping with my "no holes in the roof unless
absolutely unavoidable" policy the panels will
not be screwed directly to the roof.
Rather
I have placed aluminium battens across the vehicle,
these are glued to the roof sheets and will also have
their ends riveted to the gutter when that's installed.
We
have eight Uni Solar 64w panels and two Kyocera 120s
but I have allowed space to upgrade two of the 64w
panels with two of the new 165/170w jobs that are
similar in area but longer and thinner.

The roof layout.
As
you can see the panels cover most of the roof which
is a good thing because they form what's known as
a "tropical roof", a cooling device I have
only seen in Africa and Australia.
To
keep the vehicle cool it helps to park in the shade,
but of course this isn't always possible or even desirable
when you need the sun for power. So the solution is
to carry your own shade in the form of a second roof
mounted above the vehicle's main roof with an air
gap of an inch or so separating the two.
This
tropical roof cops most of the heat and the air gap
allows convection currents to carry the heat away.
As
the solar panels are mounted on 1" battens they
make a pretty good tropical roof, the small amount
of roof not covered by panels will have timber sheets
mounted to the battens to act as shade givers and
also provide somewhere to walk.
In
Wothahellizat 1 I used timber battens and aluminium
sheets for the walking areas, but I've reversed the
arrangement this time mostly because the timber battens
where beginning to rot.
Tue
19 Feb
I'm adding the solar panel battens today. As mentioned
before, in order not to pierce the roof with fasteners
these battens are glued along their entire length
and will be mechanically fastened to the gutter trim
on the ends.

The battens have been bent but not
cut to size so they are still too long and are resting
on the gutters.
As
the roof is slightly gabled the battens have to follow
the same curve. This is easily done by cutting part
of the way through the aluminium box section and bending
it. If I was doing this in steel I'd weld up the cut,
but I can't weld aluminium so I'll just apply liberal
amounts of gorilla snot (sealant) to fill the gap.

By cutting part way through the aluminium
I can bend it to any angle I like and retain most
of the strength of the box section.
After
cleaning and priming I apply Sikaflex and stick the
battens down. Once that's done we paint the roof with
Penetrol, it takes about 24 hours to dry so that's
it for the roof today.
I
then start making the shelves for the camera cupboard.
Wed
20 Feb
The Penetrol is dry so Chris can paint the roof with
Thermashield, a special insulating and sealing paint
for motorhome roofs.

The recently Penetrolled roof.
The
battens have to go from edge to edge across the roof
but I still need to allow water to flow along the
gutter so it can reach the drains. To facilitate this
I cut out some sections from the ends of the battens.

The cut out section on the batten ends
(circled) and the down pipe fitting used upside down
to stop surface water entering the hole in the roof.
Also
notice the upturned down pipe connector in the above
photo. I need a hole in the roof to pass all the aerial
and solar cables and there's a few ways ways to do
that.
For
example you can try to seal the holes around the wires
with glue or use proper cable glands for each wire.
The glue option never works. The cable glands do work
but I'd need one for each wire (about 12 of them)
and they only seal if you're using round wires, not
figure-eight as will be used for the solar panels.
Another
method is to not even try to seal the hole, just use
a large opening with a high surrounding lip to stop
surface water from entering, then cover it over with
something, in this case I'll use one of the solar
panels.

We
used this method in Wothahallizat 1, I had a huge
hole through which I passed several wires but which
also acted as a vent. In six years it never even looked
like leaking.
Thu
21 Feb
We're sleeping in the truck for the first time tonight,
very exciting. Not that it's ready to move in, but
our normal bedroom (the Landcruiser) is full of junk
we're taking up to our container tomorrow.
Fri
22 Feb
Well that worked a treat, it was very comfortable,
the only problem was mosquitoes as we have no netting
up in the windows yet. Actually, even if we did have
netting it wouldn't make much difference because we
don't have any walls either.
It
takes all day to drive up to our land, talk to some
neighbours, drop off the stuff and return. One thing
we learned is that just about all the neighbouring
blocks have sold recently, and that ours has increased
in value by 70% over the last two years.
After
all the losses we've made over the years it's nice
to have a win for a change.
Sat
23 Feb
We burned a mosquito coil last night and that did
the trick, no mossie bites all night.
Thu
21 Feb
I'm about to start mounting the solar panels, but
first I want to test an idea.
In
an attempt to further cut down the heat the reaching
the roof I've decided to add insulation under the
panels. There are two questions though, will it make
much difference, and will it affect the efficiency
of the panels.
Most
solar panels derate considerably when they get hot,
for example the 120-watt Kyocera panels drop their
output to 87 watts with the cell temperature at 45°
and insulating behind them probably won't help as
it will reduce the airflow.
To
help overcome this I've drilled holes along the sides
of the panels and left air gaps in the insulation.

The presumed airflow through and under
the panels.

Testing the insulation underneath a
Kyocera 120w panel.
I
leave a half-insulated panel out in the sun to see
how it goes. The area under the insulation is certainly
cooler than the other non-insulated half, but the
panel above it is also hotter.
I'll
go ahead with the idea and we'll see how it works
over time. One thing in our favour is that eight of
the ten panels we have are Uni Solar panels and these
don't derate in the heat.
Tue
4 Mar
The panels are installed, they can be hinged on one
side for maintenance.

The roof is almost entirely covered
in solar panels. What's not is plywood tropical roof
(the grey bits) or reserved for aerials.

Here's another view that also looks
down into the bedroom and kitchen.
Wed
5 Mar
Doing the solar wiring today. I've added blocking
diodes although from what I've seen most people don't
bother with them.
In
theory, when it's dark, the batteries can discharge
back through the panels. I think this discharge current
is very small and only a problem when a motorhome
is kept for long periods in the dark which presumably
will not be the case with ours once we get it out
of this workshop.
There
is however a reason not to use diodes, and that is
that you get a small voltage drop over them and therefore
a small loss of power. I'll put them in the circuit
though partly because I'm using Schottky diodes which
have a very low voltage drop, and partly because I've
had the diodes for years and may as well use them.

The solar wiring. The wires from the
panels (5 off, one per pair of panels) enter at the
top of the photo and connect to the blocking diodes
on the right. From there they go to the relay where
they are joined. The current leaves the relay in a
thick wire and goes to the regulator. Mouse over the
photo to highlight some of the details.
I've
also run the wiring through a change over relay, when
fully wired this will allow me to bypass the regulator
and connect the panels directly to the batteries.
Once
again I'm not convinced that this is a great idea
but I know that our regulator does not appear to allow
much absorption time and I would like to be able to
force more charge into the batteries manually.
When
our batteries are charged they should be taken to
about 28.8 volts and held there for a period of time
known as the absorption time before dropping them
back to the float level of 26.7 volts. Our inverter/charger
will hold them at the absorption voltage for two hours,
however the solar regulator seems to go straight into
float once the 28.8v level is reached.
The
abovementioned relay will allow me to override the
regulator and force the system to continue charging
the batteries. Of course one has to be careful here,
you can damage batteries if the voltage gets too high.
Once
again, time will tell if this is a good idea.
Tue
11 Mar
We're working on stays for the time being and it seems
that every shutter requires a different design for
its stay.
Some
are simple pieces of RHS that prop the shutter open,
while others are telescopic with spring-loaded pins
that lock the stay at the correct length.
The
simplest way I can think of to make a spring-loaded
pin is just to weld the pin to a lenght of flat bar
and weld the other end of the bar to the outer part
of the stay.

The
trouble with this is that the "spring" is
just made from mild steel and I'm worried that it
will eventually stay bent out and not hold the pin
in. If this happens there would be no way to bend
the spring back as I would have to bend it past the
stay so it can return to the correct position.
So
just in case this happens I've offset the spring,
this gives me something to bend if I have to reshape
it.


One of the more complicated stays,
showing detail of the spring that holds the pin. The
pin that does the locking is not visible here as it's
inside the stay, I've extended it through the spring
to form a small handle and that's the part you see
here.
I've
also spent a great deal of time working on the rear
shutter/deck roof. This shutter is actually two in
one, the whole thing can open as per a normal shutter,
but there's another shutter within that. By leaving
the main part closed and opening the inner shutter
two windows are revealed.
This
design should allow this rear wall to be totally open
when the area is being used as a deck, partially open
when the weather is nice and the area is being used
as part of the lounge room, closed to the elements
but allowing us to see out when the weather is bad,
or totally closed when driving or at night.
Confused?
Hopefully when it's all finished I can post some photos
that make it clearer, meanwhile here's how it looks
today.

The deck in its open position.
Thu
13 Mar
While installing the solar panels the other day I
realised that we really need a ladder to access much
of the roof. While it's easy enough to climb onto
the roof through the hatches, you can't move around
much because it's not a great idea to walk on solar
panels. This will make cleaning and general maintenance
difficult.
So
we need a ladder, but were to store it?. We looked
at those telescopic ones, they would be easy to store
but they're pretty heavy and cost a fortune.
We
finally decide on a cheap extension ladder and figure
that we can store it under the body between the rear
wheels. I even make some brackets to do this but then
realise that we may have problems with the chassis
hitting the ladder when it twists.
When
mounted in this location I have about 200mm (8")
clearance between the wheels and the ladder and the
wheel travel is only about 150mm so in theory that
shouldn't be a problem. But when the chassis twists
this clearance will reduce, also the ladder is fairly
close to the tool boxes which are mounted on the chassis.
They could also hit when the chassis twists.
So
I have to find somewhere else to mount the ladder,
and Chris comes up with the idea of hanging it under
the motor bike trap door.

The ladder mounted under the motor
bike trapdoor.
This
will make the trapdoor slightly heavier to lift into
place and may impede the winch cable a tad, but apart
from that it's a pretty good place to store the ladder.
I
also have to cut the ladder down a bit because it's
over 2.4m (8 feet) in length and the truck body is
only 2350mm wide.
Mon
17 Mar
Now that the ladder is taken care of, what can I do
with that potential storage area? There's a cranny
500mm wide and varying in depth between 75 and 150mm,
it's the full width of the truck and just crying out
to have something long and thin stored there.
Initially
I planned to put the shovel, spade, axe, and related
"gardening" tools there and have them slide
out on a long tray. But although there's 150mm of
height inside the body, anything that slides out has
to pass through a 75mm gap and two of the tools are
over 75mm in height. I could hinge the compartment
and drop it down but then it would be difficult to
reach in and unclamp the various items.
I've
figured it out, I'll make a tool rack that both slides
out and drops down. I've also decided
that, rather than make a single rack that spans the
entire body, I'll make two that go roughly half way,
so some items will be accessed from one side and some
from the other.
Each
rack is just a hinged frame with assorted cradles
and clamps to hold the odd-shaped tools in place.
I will not sheet it in to form a tray as this will
only collect dirt, although the tools are over the
wheels and will cop a lot of crap, especially if we
get into some mud. I may add a small amount of sheeting
to protect them from the majority of the stuff thrown
up by the wheels.
Wed
19 Mar
Today I'm building a mount for the spare water tank.
In all we have seven tanks, two banks of three make
up the main water storage inside the body, while the
seventh tank will be mounted under the chassis and
provide an outside source of water for washing hands
etc.
It's
other purpose is to provide an emergency supply if
we have a major leak and loose all the water from
the main tanks.
There's
a lockable tap on this tank but of course most taps
and valves provide no convenient method of mounting,
so much time is spent building a mount to hold the
tap securely.

The mount for the water tank's tap.
The round body of the tap sits in the cradle formed
from two pieces of flat bar, and is clamped down using
a bar across the threaded rods.
Thu
20 Mar
With the water tank mount and the tool racks finished
I pull them all out and set up the wash bay as a spray
booth.

Some of the recently-sprayed components.
The water tank mount in in the foreground, with one
of the tool racks hanging behind it.

Some of the brackets that hold the
tools firmly in place. No wonder it takes so long
to build a motorhome.

The finished left side tool rack.

Here's the outlet from the tank connected to the tap
with some vinyl tube. As the tank hangs below the
chassis the tap and outlet are potentially at risk
from sticks etc so they're mounted on top of bash
plates.

The finished tank mount ready for installation.

And installed. The tank sits up inside the chassis
rails and hangs down by about 200mm (8").
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