| Tue
2 Oct 2007
I'm taking a break from shutters and working on the
front door today.
I'm
hanging the door from gate hinges but as I don't want
any fittings to be visible from the outside I've mounted
the hinges inside the body and extended them with
a semi-circular arm that allows the door to swing
out.

Animation showing the door opening.

The gate hinge and semi-circular extension,
all just tacked together before proper welding.
Having
got that working I look into using the lock from the
door on Wothahallizat 1.

The door lock is installed.
There,
now we're at lockup stage.
Thu
4 Oct
The other day, while Mark and Gail where here, we
put the roof sheets on but left them overhanging the
body. The most obvious overhang is at the front where
we had a lot of extra material and today I've fold
it over the front of the roof.

The front overhang after folding, it
will be trimmed when I decide exactly where to trim
it.
But
the rest of the roof overhangs by about an inch and
I originally planned to fold the excess down over
the aluminium cladding to provide a waterproof seam,
however I also want a gutter as we plan to collect
rain water with this truck.
Also,
the old idea would have allowed the aluminium cladding
to touch the steel in several places, most especially
where the rivet pierces the material. This may lead
to galvanic corrosion.
The
terms galvanic corrosion and electrolysis are often
intermixed. In galvanic corrosion there is a flow
of current generated between dissimilar metals when
they are touching while in the presence of an electrolyte.
Electrolysis is a similar process, but in this case
the electrical current is from an external source.
There
are other issues at play that affect the amount of
galvanic corrosion, for example the distance between
the touching metals on the galvanic table and the
relative sizes of the objects, but I've seen the results
of steel touching aluminium and it's not pretty, so
in general I'm trying to nip these problems in the
bud.
So
I decide to fold the excess up instead of down and
add a 50mm steel bar all along the edge of the roof
to both act as a gutter and a fixing point for the
solar panel mounts.

The original idea (left), and as it
will be done (right). In the new version the materials
that touch are steel, whereas with the old version
steel and aluminium touched.
Note
that although the roof is steel it is galvanized so
I guess the steel gutter is actually touching zinc.
In fact all three metals are quite close on the galvanic
table so I may be being a bit paranoid, but I've never
seen problems between steel and zinc and have between
steel and aluminium so better safe than sorry I guess.
Having
done the roof folding it's time to lift the body from
the chassis again so we can paint underneath and do
a few other small jobs.
The
body is getting heavier and the legs are straining,
they also sway alarmingly with the slightest lateral
movement. As I plan to be working underneath for the
next few days we decide to X-brace the legs by welding
some RHS between them.

The X-bracing temporarily welded to
the legs.

My cheap 60kg-rated wheels are starting
to feel the pressure.

We ease the truck from under the body.
As
an added safety measure we also sling the body to
the overhead crane beam using our plasma rope we recently
bought for the winch. This stuff is amazing, 50m (162
feet) of the 11mm (<1/2") rope weighs just
a few kilos, is rated at 12.7 tonnes (28,000lbs) and
even though it is all coiled up it hardly tangles
at all.

50 metres of 11mm plasma winch rope.
The
old steel cable was much larger at 16mm (5/8th"),
was too heavy to lift without mechanical help, and
was all but impossible to handle.
With
the body safely secured about 1400mm (55") off
the floor I can work on the underneath for the next
few days.
This
is the last time the body will be off the truck, until
I build version 3 that is :-)
Sat
6 Oct
With the body off is seems like an opportune moment
to weigh the chassis again. I weighed it a couple
of months ago of course but that was before I added
all the tanks, body mounts etc.
Last
time it was 6 tonnes, what will it be now?
This
time it's 6.5, not bad considering the amount of stuff
now hanging off the chassis.
Now
I know that I will be able to weigh it again when
the body goes back on to find out exactly how heavy
that is.
I
spend the rest of the day spray painting the underneath
of the body.
Sun
7 Oct
More painting, this time it's the chassis. It's amazing
the difference a coat of paint makes, it's like having
a new truck and $50,000 cheaper.
Mon 8 Oct
Another job that needs doing while the body is off
the chassis is to drill some holes for the plumbing,
specifically the hoses running from the utilities
area to the two tanks (actually there's six tanks
but they are plumbed as two banks, so I guess we have
two banks of tanks, or two tank banks).
I
could of course just run the hoses under the body
but running them through the body should look neater
and provide more protection.
I
have two designs for this part of the plumbing, one
that fills and drains to and from each bank with separate
hoses, and the other that fills and drains with via
a single hose per bank.
I
can't really decide if there's any benefits either
way from a plumbing point of view, but the decider
is the number of holes I have to drill. With a choice
between 10 and 20 holes (really 20 or 40 because each
RHS beam requires two holes) the single-hose option
gets the nod.

Four of the holes, in the spot where
the hoses hang a left into the utilities area.

The same holes after insertion of some
short lengths of steel pipe. These pipes will be welded
and caulked to seal the interior of the beams.
Thu
11 Oct
In between painting various items I've been working
on the step runners.
I
plan to have the steps slide out from under the body
and so I have to make some runners. I'm doing this
by having some 40x40x4 RHS slide out from inside some
50x50x4 RHS and if you do the maths you'll realise
that this gives a 1mm clearance so these two sizes
are a pretty good match.
More
about these runners later when I build them but for
the moment I have to make the outside parts as these
bolt onto the body and it's much easier to make all
the brackets without the chassis in the way.
Three
of the four outside RHS lengths have to have a long
slot cut in them to accommodate brackets for the steps,
a simple enough process involving scoring a couple
of lines and cutting with a thin cutoff wheel.
There
is one thing to realise about RHS though, RHS stands
for Rolled Hollow Section (although I've also heard
Rectangular Hollow Section) and as the name implies
it is made by rolling steel into shape and welding
it. This leaves the section under some tension so
when you make a long cut along its length it will
tend to splay apart.

The slot has been cut in a length of
50x50x4 RHS.

Looking from the end you can see that
the side that has been cut has splayed by 1mm.
This
is probably not a problem for this application, just
making my 6mm slot vary from 6mm where it starts to
7mm at the open end. However it's something to keep
in mind if you do need the section to remain truly
square.
I
may still press the sides back together later, I'll
see how things work out.
Fri
12 Oct
For the time being I'm finished with the step runners
so I unbolt them and put them aside for later. I then
spray all the new mounting tabs under the body.
Initially I planned to just spray the roof and back
wall of the cab as the rest can be done with the body
on, however we've decided to re spray the entire cab
now and get it over with.
The
rest of the day is spent with me pulling parts off
the truck, Chris cleaning them, and me spraying them.
By
day's end we have quite a collection of nicely painted
truck parts. I've also removed the doors, bonnet,
windscreens etc. from the cab.
Sat
13 Oct
First priority today is to get the winch sheave block
finished. It doesn't need much as most of it was bolted
together weeks ago, but while I'm in a painting frenzy
I've decided to pull it apart and paint all the parts
and they are now ready for reassembly.
Yes
I know, painting pulleys is a bit anal, but they look
so good, and anyway with any luck we'll never use
the winch. Even if we do, maybe the plasma rope won't
scratch the paint.

The sheave block with its top plate
removed. The winch cable comes from the centrally-mounted
winch (yellow) through the rear body mount to the
sheave block, then either around two of the sheaves,
back through the mount and along the chassis to pull
forwards (blue) or straight out to pull backwards
(red).
Once that's
done I concentrate on the cab, removing the seats,
engine cover, internal panels, bumper bar and just
about everything else.
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