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Step 4: Making pegs from sugar gum, rather than traditional oak

30/10/2020

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Traditionally, in Europe and North America the pegs for the holed post (mortise) and grooved beam (tenon) are made of oak. That’s the way it’s always been.
 
In what is possibly a world first, Lachie decides to try shaving down some sugar gum offcuts. We are determined to use as many local materials as possible. What innovation ever occurred without taking a risk? Lloyds of London refused to insure the first Tasmanian clippers made of the only timber available to the local boat builders in the early 1800s – blue gum. One hundred years later they were still plying the Derwent.
 
As a Class 1 naturally durable hardwood, we know that sugar gum will have more than sufficient strength to hold the hut’s frame together. The known unknown is whether or not the dense sugar gum will shave to a taper smoothly? 
 
Lachie starts roughing out the offcut’s taper with a small axe. The sugar gum offcut is clamped down to the neck of his home-made saw horse. He mounts and begins work stropping back and forth with his two handled shaving knife, whittling the pegs down to a point. “It's smooth as…,” Lachie declares.
 
Lachie estimates that he will be able to produce the 50 or so pegs for holding the hut’s frame together in little more than a day astride what he fondly dubs his “pleasure pony.”
 
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Step 3: Chainsaw milling of sugar gum posts and beams

30/10/2020

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For a small build, chainsaw milling is another means of keeping costs down and avoiding the middle man. 
 
Lachie uses a Stihl Magnum M5 661C chainsaw as the cutting agent, with the log lain out on a Logosol M8 Sawmill. A 45yo gantry hoist designed by a friend of his grandfather provides the lifting heft to swing the sugar gum logs on and off the saw bench. These three items are capable of handling logs up to five metres in length and 60cm in diameter – more than enough to build a house.
 
“It’s empowering once you master the skills,” says Lachie. “You can cut anything you need for a hut or house on your own.”
 
Like any craft, the truly limiting factors are the hours and hours of dedication required to acquire the cutting skills and the physical strength to turn logs around and heave them onto trolleys. The old, slow ways are not for the desk bound.
 
It’s just six weeks since the trees were felled and the wood is still moist and responsive. Lachie guesstimates that green wood is four times easier to cut, drill and chisel than inert and inflexible kiln-dried timber. The downside is that it shrinks and splits more easily. Not a viable option for the ‘perfect’ finish, but fine for the rugged splendour of the 21C drop slab hut.
 
Lachie is assembling all the hut’s components off site. He’s crafting a jigsaw in his back yard and won’t put all the pieces together until they are freighted to the clearing in the ImLal biorich plantation.
 
Back in his yard, Lachie sets the sawn 175mm square posts and 150mm beams straddling a series of saw horses. He begins preparing them in keeping with the ancient mortise (old French for hole) and tenon (tongue) pattern. Chiselled and shaped beam ends will slot into grooves on post tops. Holes are drilled through each post’s tenon and corresponding mortise. 
 
When assembled on site, a wooden peg will be hammered through each hole, wedding beams and posts together into a sturdy frame. Like people standing in a line, their outstretched arms on top of each other’s shoulders.

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Step 2: Sourcing the foundation stones naturally and locally

15/10/2020

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Granite foundation stones are a perfect match for the 21C drop slab hut. When quarried locally the old way, they are low in embodied energy. So, although high in weight and density, the granite’s carbon footprint is light. An altogether appropriate product for the 21st century upgrade of our drop slab hut.
 
Known as ‘staddle’ stones, the granite foundation stones will raise the drop slab hut clear of the ground, enable air circulation and termite resistance, while offering the clearance that allows the hut to be moved around the ImLal plantation. Flecked grey-white, the staddle stones will have a solidity and natural beauty. 
 
Lachie sourced the granite from a small quarry on the flank of Mt Alexander owned by father and son team, Vin and Brent Oliver. Harcourt granite, as it’s named from the local area, formed the base of many of Melbourne’s grandest buildings in the 19th century. Famously, the structural slabs on which the Sydney Harbour Bridge sits are Harcourt granite.
 
Structural bases are these days made of concrete, the most widely used building material in the world., estimated at an average of two tonnes for every man, woman and child on Earth. A processed product, concrete not only consumes energy, but as Vin, a third generation stonemason, remarks, it’s not made for the ages like the polished tombstones he creates, rather “concrete crumbles.”
 
Most granite these days is blown to smithereens for road construction or as a filler, Vin said. In the old days, five tonnes was the limit a horse-drawn wagon could carry. Now, the smallest slabs of granite start around nine tonnes.
 
Vin demonstrated the traditional way of cutting a slab of rock. He drilled a line of holes, seeded each with two metal ‘feathers,’ hammered in wedges between the feathers, then prised the rock apart with a crow bar along the fault line that sprang up between the wedge-holes. Physical labour is the major energy input when deploying the slow, old way to split stone. Not only does it respect the rock, but the end product is a natural thing of beauty.
 
And, unlike a concrete base, the staddle stones will rise out of the earth, not smother it.
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New guards on what's left of the sequoia

12/10/2020

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Only seven of the original plot of 52 sequoias has survived the onslaught of the bouncing roos on the ImLal North site. They don't seem to like the swampy conditions much either. The sequoia pictured is as old as the young Nate on the left – 10yo and way behind Nate in the growth stakes.

Phil on the right shows his patented ring of steel  guard for keeping the roos at bay – for now.
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Building bridges on the bird survey transect

5/10/2020

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Phil continues high pruning of the ironbark

5/10/2020

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Culprit found who's churning up the earth

5/10/2020

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On the west side of ImLal South the ground is so holey, it's difficult to find a clear path in some places.

Gary was out measuring tree plots and came across the culprit attempting to hide  – as suspected, an echidna.

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Felling sugar gum as the 1st step in the 21C drop slab hut's building

2/10/2020

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The sugar gum was locally sourced from a farm plantation  at Carisbrook. It was planted in 1973 as shelter for crops and to soak up a swampy area. Lachie selected some 15 trees for posts and beams for the hut. As a Class I naturally durable timber, sugar gum is eminently suitable for this task

A quarter of a century ago, Ballarat Region Treegrowers examined which common native trees within our patch were most suited to working with wood. There were four, but in a surprise to most of us, sugar gum topped the list. 
 
Originally, sugar gum was not planted for its timber, but as shelter for sheep from killer frosts and bone-chilling winter winds and scorching summer sun. In trials across the treeless plains of the Western District over 130 years ago, sugar gum, a South Australian species, was found to grow strongest and was, moreover, amenable to coppicing. 
 
A coppiced tree is one that when cut down at its base, sends out a fresh crop of stems and regrows. Coppicing gave sugar gum the natural ability to perpetually recycle, recreating screens of leaf-dense shelterbelts, ideal for protecting sheep huddled on their lee side.
 
As a by-product, a firewood industry sprung up around the coppiced tree trunks. By the 1920s, up to 40,000 tonnes a year of sugar gum was chopped up for firewood.
 
But no-one thought to use it as timber – despite scientific analysis finding that sugar gum is one of Australia’s few Class 1 naturally durable exterior timbers. We subsequently demonstrated its suitability for decking and cladding, with Ballarat Region Treegrowers setting up a co-operative managed by farm foresters, Sustainably Managed Australian Regional Timbers (or SMARTimbers) that successfully marketed exterior sugar gum products to architects in Melbourne for five years. 
 
Some of our members are still seeking to repurpose sugar gum as a substitute for the Asian rainforest timbers that we in the developed world consume en masse, aiding and abetting tropical deforestation. BRT President, Gary Featherston, is certifying
 sugar gum for a group of farm foresters in the Western District.

But that’s a whole other story. For the purposes of this one, we and Lachie know that sugar gum is a local, it’s abundant and we can put it to a more sustainable fate than firewood.

Castlemaine filmmaker, Campbell Hynam-Smith, has been commissioned to follow the steps in the journey of building the hut and produce a 10 minute YouTube video.

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    Author

    Gib Wettenhall is interested in how  we carry out large scale landscape restoration that involves the people who live in those landscapes. That, he  believes, would build truly resilient landscapes.

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