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20 jul 1999

With the rig outside I could stand back (across the road) and finally get a view of it without any distorted perspective caused by being too close. This shot, taken with a telephoto lens, shows the truck and body in proportion and should give you a good idea of the finished shape and size.

The next day Adrian and Carrol dropped in on their way to a rally at Belangalo State Forest. Their vehicle is a 6x6 Thornecroft which they have just taken to Fraser Island. Adrian is contemplating replacing the cladding on the van with aluminium checker plate as the normal caravan-style siding is too easily damaged in the areas that vehicles like this tend to go. He's waiting to see what mine looks like before he takes the plunge.

One of the hazards of using power tools. This blade shattered as I was cutting some RHS and threw me to the floor. Fortunately the floor wasn't far away as I was kneeling on the ground at the time, but what if I'd been on top of a ladder?

While we're looking at grinders I have to say that this is absolutely the most useful tool you could own. When it comes to working with steel, if you can only afford a single tool make sure it's a large grinder. If you can afford two tools then the second one should be a small grinder.

I do just about all cutting of steel, no matter what size, with my 9" grinder and a cut-off wheel; while most grinding is performed with the 4" grinder. Occasionally, say when a spot is difficult to get into or I have a lot of grinding to do, I will swap over and grind with the 9" or cut with the 4".

I also own a 14" drop saw and seldom use it.

Once I had the basic frame up I realised that I had a hell of a lot of welding yet to do. Until this point I had been lugging the welder to and fro but this is hard work and I felt it was only a matter of time before I lost my balance with 30kg of welder under my arm.

I've seen workshops with extendable booms that hold the welder and allow it to be easily swung into position near the job. I reasoned that something similar would save me a lot of grief. Realising that most welds were within a 1.5m radius from the centre of the frame I knocked myself up a small beam trolley from some scraps and four bearings.

This trolley was designed to straddle a 50x50 RHS beam with I hung from the roof of the frame as shown below.

Here is a detail shot of the setup.

Note that the work lead is clamped to the beam; this gives you a wide range of movement before you have to re-attach it. But why not just clamp it to the beam trolley and let the current return through the trolley?, then you would never have to re-attach the clamp, it would just follow the welder.

The reason can be seen on the face of the beam in between the ends of the clamp. See that small black spot? That's where the current has arced while I was performing a weld. If the clamp had been connected to the trolley that arc may well have occurred at the contact point of one of the steel balls in the bearings I'm using for wheels. If this happened often enough the bearing could become rough or even seize.

Here we see a main join and one of the gussets I weld into all major stress points to spread the load (right arrow) and a grinding marks where a temporary stay has been removed. You'll get used to welding all sorts of temporary bits in place to hold things square or level or whatever while you weld them.