24 may 1999
A few tips I've picked up lately.
Eventually you will have to get a chain block because the various
items that need to be lifted just get too heavy. So there you
are with your nice new chain block but it only has a single hook,
not very usefull for lifting real-world objects.
What you need is a set of chain slings, but
if you go to have them made up expect a bill for more than $300.
As usual, and being the tight arse that I am, I went looking for
another way and came up with drag chains as used by four wheel
drivers. These are usually rated at ten tonnes and have a clevis
hook at each end. At about $70 each (you need two) it's not an
enormous saving but they are very usefull for other things as
I rigged them up as per the following diagram.
Note that they are hung over the block's hook
at a point about one quarter of their length. To stop them changing
this ratio as a load is applied I clamped them with D-shackles.
Here we have a very versatile slinging arrangment.
You usually use the longer lengths to either hook directly to
an item or loop the chain through it and hook it back to itself
with the clevis hooks (clevis hooks are designed to hook over
a link of the chain and provide a secure connection).
If the chain is too long for a given size of
load it can be easily shortened by hooking the shorter end to
an appropriate point on the longer end. As shown below.
Temporary slinging points
Because of their shapes many objects don't lend themselves to
being lifted by a crane. After stuggling with the rear body support
assembly I decided there must be a better way. You see it's very
inconvenient, and sometimes dangerous, to have one or two hundred
kilos of steel suddenly slip sideways because the chains being
used to lift it slid from their designated position.
The answer is to weld some temporary slinging
points to appropriate places on the item to be lifted. It takes
a few minutes but will make your life much easier and safer.
By slinging points I mean some loops made from
pieces of scrap round bar. Cut two lengths about 150mm long and
bend them in half at a rightangle.
Remember that the resultant "eye"
(right arrow) must be large enough to pass a clevis hook (left arrow).
The next photo shows a sling point on a long beam and a typical method
of slinging where the clevis hook is passed through the sling point
and hooked back to the chain.
And here we see the beam being lifted.
Try that without some firm slinging points
These temporary slinging points can be quickly
welded to an item then cut off when the job is done. Of course
they can be used many times.
26 May 1999
The mounts are finally on so now it's time for the fun stuff,
building the body. I already have the main cross members made
so they just need to be dropped on. That's pretty much how it
went down. They are too heavy to lift so few drive foward, winch
up, drive backward, winch down cycles are required.
The next thing to do is weld the first uprights
onto the rear cross member. Note the use of a large jigging square
(top arrow) and a magnetic protractor (lower arrow).
The jigging square can be knocked up from
some scrap angle and is invaluable as a clamping aid. If you make one
don't complete the square right into the corner, this allows you to
place a small tack weld or use it on an existing structure that already
has a fillet weld.
The first two uprights are in place. Now
we are actually starting to build a motor home body
Next I place the two main body rails in
From here on things went so fast I forgot
to take any photos.
27 May 1999
It's quite amazing, months go by with little
obvious change in the truck, then within two days I have half
a body in place. This is very gratifying work. It's hard going
because the items I'm working with are very heavy, however you
really get a feeling that things are moving along.
Some tools of the trade.
That will have to do as we're heading off
to Queensland tomorrow for the Townsville rally.