DESIGN and CONSTRUCTION

with Australian Hardwoods

To have a fixity of purpose you need a flexibility of method

The overarching design premise

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Steel and aluminium are both metals but we use them differently

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Likewise Australian hardwoods and traditional furniture woods are  just as different

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So lets think differently, use the advantages of hard and heavy timbers rather than run from them.

So what do we have to do to use these timbers to advantage?

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Exceptionally hard

Brilliant for tables and long wearing furniture but they play havoc on tooling and adhesion

By using tunsten tip cutting tools and modern adhesives along with very precise moisture control and techniques to increase the mechanical strength in joins the hardness of the timbers give wonerful advantages in their durability and practicality of use in our every day lives.
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Exceptionally strong

This is where the timbers shine because you can make exceptionally fine furniture which is exceptionally strong. This chair is rated by ISO 7176 for heavy domestic use, you wouldn't think it would you?

By reducing the size of the chair components we can reduce the weight but this comes at the price of rigidity. Ridgidity is primarily a function of cross sectional area and so a smaller piece of hardwood may be just as strong but it will flex more. Consequently, chairs must be made to give rigidity through design rather than the cross sectional area of its components.
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Exceptionally heavy

Heavy doesn't matter for a table or a cabinet you do not need to move often. However, for chairs it is important people can move them easily.

Simply you keep the weight down by having thinnner timbers and use good design to reduce the number of components i.e. dont be lazy.
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Fine and small joinery

Reducing component dimensions means decreasing the size of tooling but remember the timber is extra hard....

Finer joinery means finer cutting edges and sizes. Combine this with hard timbers it means care must be taken to machine it carefully. The finer sections also mean making the joints with higher precision as you cannot just sand off ill positioned joints without significantly chagning the proportion of the timber.
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Extractives

The beautiful colours come from extractives, chemicals which protect the wood from insect and fungus attack. These extractives affect adhesives and can be quite hydroscopic.

Hydroscopic (it attracts moisture and causes expansion) can be a real problem so care in moisture control and taking advantage of the hysterisis effect is important. Choosing the right adhesive is important and cross linked PVAs work well and so do epoxies. However there is no universal glue for every species.
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Expansion and contraction

The denser the timber the stronger the expansion and contraction and the more pronounced. Unfortunately this is not an advantage of the timbers but there are ways of dealing with it.

Firstly it is a matter of moisture control and seasoning of the timbers keeping in mind the hysteresis effect. The hysteresis effect the expansion after shrinkage -due to moisture content changes- is a tiny bit less each time. Consequently timber becomes more stable over time - but it will never stop expanding and contracting along with changes in air humidity. Then it is designing the furniture to allow the timber to move with changes in moisture content by using specific hold down methods and designs. They are not mysterious, it is just taking sound solid wood design and making to the next level.
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Machining

The timbers are not only hard but many have interlocked grain, some contain silica (like sand) in the cells which means the latest spiral cutters and tungsten tip cutting edges are vital.

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Drying

The density of the timbers and the resulting slow drying rate - from when the timber is green - means that the surface can easily shrink faster than the inside and split. Drying has to be very controlled to get split free timber.

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Glueing

High levels of extractives and dense timber can hinder adhesive bonds, particularly as many epoxy glues grip mechanically rather than bind chemically as do water based glues. However water based glues can cause localised and unwanted timber expansion.

So how do I, Peter van Herk, do it?

The Swan Chair, Winner of best design, Australian Furniture show 1996

Chairs

I like designing chairs the most, having two design awards under my belt from years ago. Chairs are the ultimate in design with the hardwoods as they need to be fine but also strong. A high degree of accuracy and design and engineering is needed to make fine chairs that satisfy ISO 7176 for heavy domestic use.

6m x 2.4m suspended Forest Red Gum board room table

Tables

Wow!!  I have built some big tables, the 6.0 x 2.4m boardroom table suspended from the ceiling was the largest. However, bragging aside, a table is a surprisingly emotional piece of furniture, it has the 'wow' appeal of a big piece of timber. Care goes in to the selection and then balancing the design to go with the fine chairs and the home and desires of the client.

waiting for the brass stay and leather interior

Crafts

Recycled timbers are wonderful, not only the vibrant colours and the marks from a history of use but they are relatively stable having seasoned over decades. Fine sectioned timber is important to make the craftworks light enough to handle though the machining and construction process is fraught this matters like finding attractive screws small enough that will not break off.

Buffet made from the varied colours of Spotted Gum

Cabinetry

Designs have changes significantly since I stopped making furniture in 2000 so this Spotted Gum buffet is not up with the trends. However, you can get the idea that anything can be designed and made to impeccable standards.

Reception seating for the Australian embassy foyer in Berlin circa 1997

Commisions

The above was the reception bench for the Australian embassy in Berlin. Commissions for embassies, Kirribilli House, private customers and customers in Japan, USA and Australia wide. See the web page on commissions here.

Re-sawing recycled timber

Sourcing timber

In the past I bought semitrailer loads of timber and dried them in my specially designed solar assisted kilns to maximise quality and appearance.

Nowadays I seek out recycled timbers and use the metal detector very carefully, re-saw and machine.

Sometimes it takes a lot of time to find enough matching timber for a dining setting but it is definitely worth it.