Festool Owners Group

GENERAL DISCUSSIONS => Finishing and Painting => Topic started by: pyleg on December 28, 2017, 03:16 PM

Title: Suggestions for Finish for figured Eucalyptus?
Post by: pyleg on December 28, 2017, 03:16 PM
I have some nicely figured but very light-colored eucalyptus (gum) that I intend on using for boxes.  I'd like to bring out the figure without without making the wood overall much darker.  A lot of the Google advice seems to pertain to outdoor uses, and these boxes would be for in home use.  I'm the hobbyist type so nothing that requires a sprayer :-)
Title: Re: Suggestions for Finish for figured Eucalyptus?
Post by: Untidy Shop on December 28, 2017, 05:28 PM
I would go for an oil finish. This is a common finish used here with furniture made from  Australian Hardwoods most of which are in the Eucalyptus Family. They can be waxed as well if desired.

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What species of Eucalyptus do you have, as the Color range can widely very from light pale pinks - browns - brown/ black - orange - red.


https://www.daf.qld.gov.au/forestry/using-wood-and-its-benefits/wood-properties-of-timber-trees

Title: Re: Suggestions for Finish for figured Eucalyptus?
Post by: pyleg on December 28, 2017, 06:30 PM
I would go for an oil finish. This is a common finish used here with furniture made from  Australian Hardwoods most of which are in the Eucalyptus Family. They can be waxed as well if desired.

What species of Eucalyptus do you have, as the Color range can widely very from light pale pinks - browns - brown/ black - orange - red.


Thank you.  I'll do a test with some Odie's oil I have around. 

Blue gum.  Some of it was marketed as "Australian" by species, but I think it was all harvested in California(?).  It's hard to see but has a bee's wing figure
Title: Re: Suggestions for Finish for figured Eucalyptus?
Post by: aloysius on December 28, 2017, 11:22 PM
With some 700 true spp. of Eucalyptus, plus an innumerable number of hybrids & related spp., there's a whole range of individual characteristics which makes it rather difficult to determine exactly what you have.  Having said that, however, there's a distinct possibility that you may have either "Tas. Oak", a commercial aggregation of about 4 main spp. of mass produced timber, or perhaps "Blue Gum", the overwhelmingly prevalent plantation spp. (Eucalyptus globulus) originating commercially in foreign climes.

One is soft(ish) the other hard & resilient, as much as any rapidly grown plantation spp. can possibly be...

I agree with oil finishes, particularly the lighter or more neutral varieties of maybe Teak or maybe boiled linseed, applied with clean, rust-free fine steel wool (never with water-based finishes however) or a synthetic equiv. or alternatively a clean lint-free cloth.  An initial wash of sanding sealer may assist in keeping your surface smooth between coats.  Buff with a similar but clean product after it dries.  Some eucalypts like waxes, while some oilier ones won't.

For a hard-working coating, the synthetic polyurethanes (I prefer oil-based) give a tougher, more resilient or even waterproof finish if preferred.  Thin the first coat with about 10% turpentine (sorry, I don't know your local name for this... mineral spirit??) & denib between repeat coats with folded papers.  Hope this helps.
Title: Re: Suggestions for Finish for figured Eucalyptus?
Post by: pyleg on December 29, 2017, 01:49 AM
With some 700 true spp. of Eucalyptus, plus an innumerable number of hybrids & related spp., there's a whole range of individual characteristics which makes it rather difficult to determine exactly what you have.  Having said that, however, there's a distinct possibility that you may have either "Tas. Oak", a commercial aggregation of about 4 main spp. of mass produced timber, or perhaps "Blue Gum", the overwhelmingly prevalent plantation spp. (Eucalyptus globulus) originating commercially in foreign climes.

Thank you for the education and advice!  I looked up the original email solicitation and it says "Tasmanian blue gum," but doesn't indicate species:

"Native to Southeastern Australia and the island of Tasmania, this is a large evergreen tree that grows up to 297 ft. tall and 6 ft. or more in diameter with most growing from 100-175 ft. feet tall. The tallest currently known specimen in Tasmania is currently 297 ft. The natural distribution of the species includes Tasmania and southern Victoria (particularly the Otway Ranges and southern Gippsland). This species was planted in Hawaii in 1865 after being successfully planted in Western California in 1856 from Australian seeds.  Blue Gum trees have been a part of the California landscape since the Gold Rush.  They were planted in huge numbers well before the timber speculation wave hit. Part of the reason for planting the trees was for windbreaks on farms and orchards, as seedlings can grow 25 feet per season for several years after planting, and don't need much additional help growing. Tasmanian Blue Gum leaves are used as a therapeutic herbal tea.  The flowers of the tree are a good source of nectar and pollen for bees.  The tree has naturalized in California and Hawaii and about 1915 was starting to be viewed as an invasive species in California.  As of 2014 it was considered the #1 invasive exotic species in California. The wood is closer to the density and working properties of Brazilian hardwoods than any native North American hardwoods and takes a very nice polish."

So whatever species it is, is hard, fast-growing, likes California, and makes tea :-) 
Title: Re: Suggestions for Finish for figured Eucalyptus?
Post by: aloysius on December 29, 2017, 02:22 AM
I'd imagine that E globulus is a genuine contender for the most numerous tree on earth.  Thanks to its ubiquity as a plantation spp.  It's not just in Cali that it's considered an invasive pest spp. either.  In other parts of both Americas, throughout the South Asian subcontinent, S.E. Asia, Southern, N.W. & the horn of Africa & the Iberian peninsula there's countless millions of hectares planted & now (unfortunately) self-sown.

It's ideally suited to impoverished, esp. acidic & low phosphorous soils, has an extraordinary deep root system that seeks out & depletes aquifers, rice paddies, whatever & has an allelopathic (toxic) effect on much native vegetation.  Growing on better sites to over 100m in height, competing native vegetation doesn't stand a chance.  The strong, volatile eucalyptus oil bearing leaves, extreme drought tolerance and not just fire resistance but active wildfire propagation characteristics (long candlebark, dead staghead old-growth form, highly inflammable oily soft tissues with thick, deep insulative bark makes large old growth stands a distinct (even extreme) fire hazard.

Taxonomically speaking, it's just about the "perfect weed".  That its timber is strong, hard & beautiful, its soft tissues perfect for oil distillation, excellent for firewood, shipbuilding, wharf piles & railroad sleepers makes it just too darned useful too.  For every local environmentalist decrying its negatives there's whole local third world economies & communities benefiting from its presence.  Addis Ababa (Ethiopia) was, until Blue gums were planted, a hot, treeless, virtually shadeless "desert" stripped of virtually all vegetation for fuelwood & goat fodder.  Blue gum was used to help the British Empire expand its naval installations & railroads across vast swathes of Africa & South Asia.  It helped (in its humble way) to build the Empire.

Not bad for my state's floral emblem that here only exists in small, isolated, non-contiguous stands.
Title: Re: Suggestions for Finish for figured Eucalyptus?
Post by: HarveyWildes on December 29, 2017, 09:22 AM
I like the oil approach as well.  I've used it on Lyptus.

My experience was that wet sanding to higher grits (in the 1000 range) with the oil brought out fine grain detail that otherwise seemed to be obscured.  In my case, the project justified the extra work.