Spotted Gum

[sebastiaan56]

I've managed to score some very attractive Spotted Gum. The pieces are not wide enough for backs but sides an certainly necks are a possibility. I know it's used for tool handles so stability shouldn't be an issue.

Does anyone have any experience with this timber?

[curly]

I've been researching Spotted Gum -Corymbia maculata recently as a back and sides timber . It's very available , often figured , colour in the northern variant is a good chocolate,red and its a good bending timber . The one thing that has stopped us stocking it as a tonewood is it's moderately high movement in service . The radial unit shrinkage or change coefficient values are 0.0032 .
Incidentally movement in Eucalypts is often less than people think . For example Red Gum is .0022 . Brazilian Rosewood 0.0023 . Red Gum moves less in service than B.R.!

Pete

[charangohabsburg]

The pieces are not wide enough for backs but sides an certainly necks are a possibility.

3- and 4-piece backs can look absolutely amazing when using contrasting separation strips between the pieces.

[Mark McLean]

I love spotted gum for its colour and texture. If it has the physical characteristics to work as a tonewood I would love to use it. The trees don't develop the girth of most species that we think of as guitar-making woods, so it might be necessary to adopt Markus's suggestion for a guitar back. But a spotted gum three-piece back might be just gorgeous.

[jeff crisp]

I know from my flooring days that not all coatings will adhere to it properly. Seen many with delamination and unfortunately caused a couple myself in early days.

[curly]

Small girth is only a result of spotted gum being heavily logged . For a class 2 durability timber it saws and dries very easily and quickly .
There is a particularly big old Spotted Gum on the main road that crosses the Richmond Range ( north to south ) inland of Grafton in northern NSW that measures 1.8metres dbh . Old growth trees will often go aver a metre .
Pete

[sebastiaan56]

Can you tell us more Jeff? Id like to avoid the learning curve

[jeff crisp]

Can you tell us more Jeff? Id like to avoid the learning curve

With flooring a fast drying solvent based sealer coat is the main form of prevention. Like floors there are many coating options and systems being used for guitars. If you're spraying, the speed at which the coats flash off may be enough...I don't know. The main problem with coating oily, waxy, resinous timbers is the contaminant leeching through the first and then subsequent coats. Coating as soon as possible after final sanding is always good practice and wiping with a suitable solvent (thinking about nitro here) between coats can help. Shellac may be helpful if a sealer coat is not avialable for the product you use. Any kind of rubbing oil (as a finish) should probably be o.k. and 2 part products of any elk may have an advantage.
Sorry I can't give you a definitive answer, just thought I should alert you to potential problem.

[sebastiaan56]

Thanks, I'm a TruOil guy so it should be ok.