Peter Coombe Mandolins and Guitars
Experiences with Mountain Ash
I have had a number of enquiries from various people as to whether I had
tried Ash for the backs of my mandolins, so recently I decided the time was
right to try it. Ash is one of the tallest trees in the world, with some
specimens rivaling the Redwood trees of coastal California in size. The wood
is readily available in south eastern Australia,much of it quarter sawn, and
with a bit of hunting around, one can find some quite attractive fiddleback
pieces. Colour is usually a uniform bland light brown, not particularly
outstanding in the colour department, and the grain is open pored and resin
pockets are not uncommon.
I had a slightly figured piece of suitable size that had been sitting in the workshop for around 7 years so decided to give it a go. Also sitting in the workshop for a number of years were two very nicely fiddleback figured pieces suitable for sides. Ash tends to split if not quarter sawn so neckwood is a bit of a problem, but over the years I have managed to find a piece with a bit of figure and just a bit of splitting that could be easily worked around. So I had all the necessary pieces to make a mandolin or two.
The first thing was to join and carve the back. Upon slicing in half to bookmatch a back, I discovered a number of very small splits, but thought most, if not all would
carve out. Maybe this piece had not been dried properly before I bought it. Carving the outside of the back was a bit of a chore. This timber is quite hard, moderately heavy and blunts tools, although is not as destructive to tools as Queensland Walnut or Jarrah. Now about the splits - I was wrong, not all did carve out, but I decided to persist and repair them with superglue. I was quite keen to see how the timber behaved acoustically and had already spent a fair bit of time on carving so did not want to waste more time. What followed was quite a painful process of fixing one split, only to find another the next day, and then another the next, but eventually everything was patched up and pretty much invisible. But I really was beginning to wonder if it was all worthwhile. I then carved out the interior of the back, sanded and thicknessed it about right. The good news is this wood is really strong and stiff, so strong and stiff that it made a light and responsive back. Quite promising acoustically, and I am sure it would work as a backwood in a mandolin.
Next job was to bend some sides. This is where life became difficult and it all fell apart. The first set of sides proved to be difficult to bend around the body of the
instrument without breaking, and utterly impossible to bend around the tight corners without breaking. I tried all the tricks I have learned over the last 10 years or so to no avail. Next I cut another set of sides from the other piece of ash which also proved impossible to bend around the tight corners, although it was a lot better than the first set. It might be possible to bend violin sides, but mandolins have thicker sides which make the tight corners around the teardrop more difficult. It might also be possible to bend unfigured strightgrained Ash, but it would look somewhat plain and unattractive in a mandolin. At this stage I was seriously questioning whether all the timber I had was actually Eucalyptus regnans. One piece was noticeably darker when wetted and coated my bending iron with a dark deposit. One can never be certain since E. regnans is marketed together with E. obliqua and E. delagantensis.
OK, time to re-assess if this timber really is suitable for a mandolin. The conclusion for me is no. Although life was not meant to be easy, it was also not meant to be this difficult! There are other native Australian timbers that are suitable and are a damn sight easier to work with. Some figured Myrtle, for instance, can be difficult to bend (although not as bad as Ash), and can also sometimes suffer from small splits if dried too quickly. However, it is a delight to work with and has proven to be acoustically superb in mandolins. It also finishes superbly since it has a very fine grain texture, andsome pieces can be a very attractive deep reddish brown colour. Myrtle remains my favourite backwood for my mandolins.
I know some other Luthiers have used Ash with success because they have told me, so if any readers would like to rescue some fiddleback "Ash" from the fireplace you are welcome to it. It does make great firewood.