Turning green

[brainstrust]

I can see it's been discussed a few times....Is anyone currently having regular success turning green wood?
I've tried a few times and it is refreshing to be turning something on the softer side, quite enjoyable!
Unfortunately soon ruined by cracks and warping.
I think I'm not doing bowls thin enough and bottom too thick and inconsistent.
Oh and also not drying in a box or bag or something!
Any cool tips?????? :C

[Kidbee]

If it is of any comfort, Richard Raffan (the author) turned green wood with great success. Think he used a microwave for drying, turned chunky and refined them when they were dry. I see you live in Canberra where they spend all our money, so I am sure your local library would have a ship load of books that he has written.

[dai sensei]

I have had both success and failure from green turning. It greatly depends on what sort of timber and how it was cut (1/4 or flat sawn etc).

Turning thin straight up and just accept it won't stay round. Hats and light shades are common ones but timber choice is critical.

Rough turning a blank and then finish turning it down the track works pretty well. Cracks don't worry me too much as I can fill them with resins, or make them into an artistic feature, like zipper/shoe laces etc. Biggest failure for me is not leaving enough meat. I did some Chinese Raintree bowls that went from 35mm thick to 15mm and very oval. Luckily I know someone with an oval chuck so I could still save them.

Microwave ovens can work but they can also cause internal cracking that isn't visible until you turn the blank. Silky Oak is a classic example. Dehydrators work better IMO. I also just bought a smoker oven, so I can use the water tray option, thus effectively giving me a small kiln.

[Kidbee]

I have had both success and failure from green turning. It greatly depends on what sort of timber and how it was cut (1/4 or flat sawn etc).

Turning thin straight up and just accept it won't stay round. Hats and light shades are common ones but timber choice is critical.

Rough turning a blank and then finish turning it down the track works pretty well. Cracks don't worry me too much as I can fill them with resins, or make them into an artistic feature, like zipper/shoe laces etc. Biggest failure for me is not leaving enough meat. I did some Chinese Raintree bowls that went from 35mm thick to 15mm and very oval. Luckily I know someone with an oval chuck so I could still save them.

Microwave ovens can work but they can also cause internal cracking that isn't visible until you turn the blank. Silky Oak is a classic example. Dehydrators work better IMO. I also just bought a smoker oven, so I can use the water tray option, thus effectively giving me a small kiln.

Do you mean a zipper like this?

[Paul39]

As above some timbers crack & some don't.

There is lots of information on rough turning green and then drying, do a search.

I have good luck most of the time with the following, with bowls:

Turn soppy wet green with wall thickness 10 -20 % of diameter then stick in a crock pot overnight on low, then drain and wrap in 7 layers of newspaper and let dry several months.

Turn green with wall thickness as above, and soak in 1/2 water and 1/2 hand dishwashing liquid for 2 - 6 months. Drain and wrap in 7 layers of newspaper and dry 4 - 6 months. This has also worked on full rounds with pith in the middle for vases. I did drill a 20mm hole down the middle to let liquid in and help dry.

Turn green with wall thickness as above and wrap in 7 layers of newspaper and let dry 2 - 5 months.

One suggestion is to rough turn fresh cut timber, thickness as above and immediately boil for two hours. My crock pot slow / cooker is a variation.

I have rough turned partially dry bowls and then let them sit in the shed for months or years, some crack and some don't.

US black walnut, cherry, and hard maple are pretty stable. Red oak cracks no matter what I do. It has a nice color and figure so I just fill the cracks with contrasting tightly packed saw dust and glue, and finish.

Turning Bowls by Richard Raffan is a good book. He covers turning green. https://www.amazon.com/Turning-Bowls-Richard-Raffan/dp/1561585084

Some turn a green bowl fairly thin with a round bottom in one session and let it warp and move all it wants.

Depending on the timber, how it is cut, the figure, how it was dried and how dry, and how you hold your mouth while turning, it may crack or not.

I had a piece of red oak that I had cut into an octagon and gouged out the inside with a Skil Saw that was in the house for about 7 years. Not the hint of a crack. Put it on the lathe, made a bowl, sanded & put on first coat of Tung oil, came back next morning and it had 3 cracks. Filled cracks and finished.

[Richard Hodsdon]

turn walls to thickness of about 10% of diameter, AND base should also be of similar thickness. I find biggest cause of cracking is when walls and base are of different thickness because then you get uneven stresses and then you have designer firewood. Also some woods will crack no matter what, and when the tree was cut down Spring, winter will also affect it.

[lovetoride]

If it is of any comfort, Richard Raffan (the author) turned green wood with great success. Think he used a microwave for drying, turned chunky and refined them when they were dry. I see you live in Canberra where they spend all our money, so I am sure your local library would have a ship load of books that he has written.

Or better still...Come and join us at the ACT Woodcraft Guild (http://www.woodcraftguild.org.au/) to join in the woodturning SIGs and attend one of the frequent workshops run by our own local Richard Raffan!

Jane

[Skew ChiDAMN!!]

And one important detail that has been neglected, especially if you're sourcing your own logs: remove the heart of the log when cutting your blank for turning. I tend to cut about 1" each side, depending on the initial size.

The further from the heart - ie. the less curved the rings appear in the end-grain - the lower the degree of stresses from drying.

Ditto for knots and some inclusions which form target shaped ring patterns in the side of your proposed turning. The centre of growth patterns are the most likely spots for rifts/splits to start forming, due to the way timber dries and are why the ends of logs split in a star pattern, called 'star shakes.'

If you really, really, really want to include these, either dry the blank thoroughly first or rough shape it down to about 1" wall thickness while green and then set it aside in a box full of it's own shavings to let it dry/move slowly for a few months, before eventually turning it down to final size and shape.

FWIW, if you start with a 4" thick branch, it's unlikely you'll successfully get a 3" or 4" round item - let's say a goblet - out of it. If you have a 12" diameter log, you should be able to cut out the heart and have two potentially 5" tall x 10"-11"dia. bowl blanks. Provided the log was as long as it was wide, of course! ;)

Basically "select your timber very carefully" and it should show dividends. :D

[hughie]

I have done a fair bit of it with out to many stuff ups, mainly Camphor Laurel as its stable. Many of the hardwoods I use it isn't really practicable to do so. So species selection is very important.
As for fast curing or seasoning, there are plenty of methods to help. Soaking in meths or DNA after roughing for 24hrs to a few days. Soft timber responds well ie Camphor Laurel.
But in land hardwoods, ie Gidgee, Deadfinish, Inland Rosewood and so on air dry over time seems to be the most reliable.

[brainstrust]

What no heartwood???? Damn.
I'll keep at it now and then but think I'll mostly just used seasoned.
I have a stack of Yellow Box and a little Tassie Blackwood I think I'll just leave alone for a year or so!