Hollow forms

Hollow forms are simply a piece of wood shaped into a sphere (of sorts) with a hole in the top and hollowed out inside. Sometimes, a piece of contrasting wood is added to the hole to create interest or to create a much smaller hole.

I have made a number of hollow forms over the years, with or without a contrasting insert. They can be difficult to make depending on the type of wood and size of the piece. Part of the process is to have the wood fixed to the lathe by a small spigot on the bottom while the hollowing process is done. The risk is that at high speed a catch (the chisel digging into the wood)will often cause the piece to fly off the lathe and land somewhere in the workshop – not good for the turner or the piece!

I have used liquidamber and silver birch for the hollowed section but I have also used yellow box, red box, grey box and red ironbark – all Australian hardwoods. If using liquidamber or silver birch, both light coloured European woods, I have used red ironbark or redgum as the contrasting insert.

These forms are mainly decorative; there is little utilitarian use for them but they are pleasing to the eye and very tactile to touch.

Liquidamber with red ironbark insert.
120mm x 110mm

This was an interesting piece and I think my first attempt at a hollow form using grey box. Grey box is one of the hardest Australian timbers and is quite unforgiving – a slightly deep engagement with a gauge will very quickly turn a potentially nice piece into firewood!
However, it shows the variation in colour from a deep brown to a light brown. This is common in eucalypts.
This piece was given to an American couple returning home after working in Australia for a couple of years.

Red Ironbark & Grey Box

This piece was commissioned by a friend who wanted an Australian made present for her sister who lives overseas.
It exhibits some checking and grub tunnels but also has grey-brown patches which are probably incursions of sapwood into the heartwood.
Hard to work and requiring the tools to be sharpened very frequently (every few minutes) hollowing the inside is arduous and often the walls are left quite thick. As a result the piece is heavy and, if nothing else, makes a very effective paperweight.
The funnel is grey box which also is a very hard eucalypt but had a very tight grain and a texture that could be described as lustrous when sanded to a very fine grade (about 1500). It too, polishes very well. On this piece you can see darker patches which indicate some pressure applied to the living tree either by wind or branches diverging . On other pieces I have made eg chessboards, these are much more prominent and become a feature of the finish.

Three Aus Hardwoods

Liquidamber & Red Ironbark

Some years ago some friends in Melbourne had to remove a very large Liquidamber tree from their backyard because their neighbour complained about it – it was almost on the fenceline. I was invited to go and take as much as I wanted – so I did! It is also in Australia -obviously!
Liquidamber is distributed throughout China and Asia but apparently disappeared from Europe due to extensive glaciation and Western United States through climate change.
It is a moderately hard softwood and easy to work. Although generally clear of splits and checks it does have knots where branches grow from the trunk. Having a close grain it polishes well.
Red Ironbark, on the other hand, an Australian eucalypt is very hard and unforgiving but it is a beautiful wood – I think it is my favourite. It rewards lapses in concentration with very large ‘catches’ which take a lot of work and redesign of the piece to fix. Very hard and with a very tight grain it polishes very well.
Finished with a polish comprising tung oil and carnuba wax it has darkened a little with age.
I rather like this piece and think I will keep it.

London Plane Tree & Grey Ironbark

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The London Plane Tree was taken from a tree that had grown in Albert Street, Surrey Hills, VIC and was felled by Boroondara Council in April 2020. Rough turned in September 2020 the bottom section was finished in August 2021. The funnel was turned from several laminated offcuts of grey ironbark left over from a deck on my daughter’s property.

The London Plane Tree is a European reasonably hard softwood of the sycamore family. It has a very interesting grain. It is used extensively in cities as street trees because of their large leaf canopy. They are also a favourite food source of Corellas who swoop in and leave the street yellow with dissected seed pods.

Lilli Pilli & Grey Ironbark

I havehad this piece of Lilli Pilli sitting in the shed for about 15 years and finally decided to do something with it. It is a moderately hard wood and it is also susceptible to attack by borers. There is evidence of borer activity which is more easily seen in the right hand photo. The borer holes contain a lot of very fine dust so wearing some sort of breathing protection is essential.

There were also several splits in the wood and many, but not all, were filled with epoxy resin to manage the risk of the piece splitting while on the lathe. The circle is coloured deep red epoxy resin.

The funnel is grey ironbark and is a lamination of three 19mm thick offcuts – one should nevery discards offcuts as they have a habit of becoming useful!!