Tasmanian Cider Gum tree - eucalyptus

[Chriscb]

Afternoon all,

Well here's the thing. In October 17 my friendly tree chap drop off this huge example of a eucalyptus tree - the Tasmanian Cider Gum tree is one of the few that grow well in the UK. The big bits must be about 3 foot in diameter. I rough turned about 40 bowls, vases, platters and pots over about 3 weeks, set them all in shavings and large paper bags and waited. Long story short - I've only 8 pieces that haven't cracked completely, split, etc et al. Strange thing is the pen blanks I've cut all seem to be OK - turned one in January and it's not cracked. Just for completeness I've dried other woods without losing so many turnings.

So the question is - is my failure rate about average? Any tips as how to turn pieces and keep them whole? It's good to practice turning big bowls ( 5" x 20") but I'd really like to keep one - the grain is very good.

Thanks.

Regards,

Chriscb

 

[Phil Dart]

I don't have enough experience of that particular wood in its green form to comment on it specifically - it may be that it's a particularly tricky timber to season, but in general when turning green bowls, the trick is to make sure that the pith is not included, the wall thickness is even throughout, usually about an inch, and that you take all steps top slow down the moisture loss as much as possible.

You may find that simply putting it in shavings in a paper bag is not enough. You could substitute paper for plastic, which you tie up then turn inside out every couple of weeks, or you may find that you need to seal the wood more thoroughly than just covering in wood shavings. In any event, the cracks are appearing because the wood is loosing moisture either unevenly or too rapidly, or maybe both. (I'm assuming that you did not include the pith in any of the pieces)

 

[Neil Lawton]

We took one down and you could hear the stuff cracking in the boot on the way home!
I got some great pen blanks but most bigger bits had hidden shakes even if it looked good. Most went for firewood in the end but I found a bit that looked sound and slung it on the lathe. The morning after it looked like this!

 

[Bammer]

I had the same result, extremely heavy because of the water content. But when dried did really well in the wood burner

 

[Chriscb]

Thanks for the reply chaps - reassuring that I'm no worse than average. Some of the grain is stunning - like the peice from Neil. Maybe the key here is to go for smaller turnings for keeps and use the big lumps just for practice. Occasionally I'll get lucky with a good bowl!

Regards,

Chriscb

 

[wm460]

I though you have found a new specie till I googled it, It has another name near where I grow up.

"in the Noarlunga and Rapid Bay districts of South Australia as "bastard white gum."

Eucalyptus gunnii - Wikipedia

 

[Chriscb]

I though you have found a new specie till I googled it, It has another name near where I grow up.

"in the Noarlunga and Rapid Bay districts of South Australia as "bastard white gum."

Eucalyptus gunnii - Wikipedia

He he, nice one. Given that the wood looks brilliant when turned, but as has been said elsewhere, cracks virtually immediately I can certainly concur!

 

[lignaterrae]

Chris,

Chris, your experience of Cider Gum is entirely typical. It exhibits just about every drying defect you care to imagine; huge shrinkage, collapse and distortion, splitting, tearing. When it looks like you have a usable chunk that looks dry it often will have one final heartbreak left for you - honeycomb shakes. A seemingly good block when cut into will contain slash-like internal cracks that don't reach the surface and ruin the whole block.
Mind you, once you have got a piece that worked it's a mighty attractive timber and the pieces that failed do make excellent firewood...

Even when cutting for pen blanks, for me no more than 20% make it through the drying process alive.