Woods To Know: Imbuya

Woods To Know: Imbuya

Imbuya (Ocotea porosa)

by Peter MacSween

Consistency is not a word commonly used when describing Imbuya (aka, Imbuia, Brazilian Walnut). The wood displays an astonishing variety of figures with many unique and distinct colour variations. Each individual tree is unique with the only common characteristic being its recognizable cinnamon like odour.
 
Imbuya is from the Araucaria rain forest of southern Brazil, which has a distinct ecosystem from the other areas of Brazil. Most of the trees come from the states of Parana and Santa Catharina. It’s a large tree often growing to 130 feet with diameters of 5-6 feet. It is an important resource for Brazil, although its numbers have declined due to habitat degradation and over exploitation. This is a slow growing tree and that makes conservation efforts difficult, but many groups are focused on its restoration. 

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The heartwood is typically a medium to dark colour range with olive, gold, black and yellow overtones. The colours can weave in and out giving the wood a dynamic appearance. Burl, curly, fiddleback, quilt, chicken scratch, and blister are some of the figure types associated with Imbuya. The sapwood is a creamy white distinct from the heart. Overall, it has a variable visual palette. 
 
The consistent fine texture makes it an ideal candidate for turning and carving. The wood has a natural luster that can give finished pieces a polished look, and the grain is usually straight; however, the many figure types can give woodworkers cause for concern.  
 
The wood works well by machine or hand. Figured wood requires sharp tools, low cutting angles and slow feed rates. Surfacing to final dimensions on difficult pieces may have to be done by sanding to avoid tearout. The wood glues well and holds screws and nails with no problems. It finishes beautifully. Oil finishes will bring out the grain, enhancing its appearance. Finally, this is a very stable wood when dried. 
 
Imbuya is used for fine furniture, veneer, panels, turned and carved items as well as musical instruments, gunstocks and flooring. Often called Brazilian Walnut (although not related botanically), it can be stained and finished to look like Black Walnut. In fact, with its varied appearance, Imbuya is a natural mimic. Skilled finishers often use it as a substitute for many others species of wood. 
 
Commercially, solid Imbuya never enjoyed much success. There is too much variation between individual trees. Sorting for consistent appearance is difficult and waste factors are high. This doesn’t apply to the individual woodworker where skillful design can exploit Imbuya's unique appearance. 
 
It did find a home in the realm of architectural veneer. Here large trees yield huge amounts of sequenced veneers for large panels. The amount of variation within a single tree is small, so architects and designers can specify Imbuya for large commercial projects.

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Imbuya end grain
 
Imbuya’s scent is distinctive and can take over your shop. The scent is most apparent when the wood is being milled and will fade with time. Like colour, scent is produced by chemicals produced by the tree and is indicative of species that are durable. Imbuya is no exception. Some woodworkers may react to the scent, so dust mitigation is a good idea until you can determine your tolerance. 
 
Solid Imbuya lumber is getting harder to source. Large dimensional lumber, once common is now on the decline. Turning, rifle stock and musical instrument pieces are more common. Veneer is very common and is a great way to introduce your self to Imbuya and help conserve the resource. Expect to pay more for highly figured/coloured wood. Imbuya is highly recommended for any project needing a visual boost. It’s a joy to work with and is one of the woods all crafts people should experience.
 
 
Average Dried Weight41 lbs/ft³A measure of its weight at 12% moisture and an ambient temperature of 70°F.
Specific Gravity.66A measure of the ratio of its density compared to water (at 12% MC)
ShrinkageRadial: 3.0
Tangential: 6.4
Volumetric: 9.5
Radial (the amount of crosswise shrinkage);
Tangential (the amount of lengthwise shrinkage);
Volumetric (the total amount of shrinkage.)
T/R Ratio2.1A measure of the uniformity of tangential to radial shrinkage.
Janka Hardness970 lbfA measure of resistance to denting and abrasion.
Crushing Strength6,780 lbf/in²A measure of compression strength parallel to the grain.
Colour
Heartwood color can vary substantially; typically medium to dark brown, sometimes with a reddish, golden, or olive-colored cast. Light grayish yellow sapwood is usually differentiated from the heartwood. Burls and wildly figured boards are commonly seen.
GrainStraight, sometimes wild or burl-like patterning.
TextureMedium to fine.
Workability
Produces good results with both hand and machine tools. However, pieces with wild or irregular grain may present challenges in surfacing and other machining operations. Turns, glues, and finishes well.
Uses
Furniture, cabinetry, flooring, veneer, boat building, gunstocks, and turned objects.
Price$8.40 4/4

 
  
Photos and Specifications Courtesy of: The Wood Database