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oakchip
16th Dec 2009, 12:23 AM
G'day all
I have read a couple of posts where some members have turned pieces from green timber. Do you rough the piece out and then let it season to allow for distortion. If so, is there any treatment required after the roughing out.

Cheers
oakchip

Texian
16th Dec 2009, 02:40 AM
G'day Oak,
Many (most?) turners in the U.S. work with green timber. The usual guideline for bowls is to rough out to a wall thickness of 10% of the bowl diameter. Beyond that there are many different methods of drying the roughouts.
Place in paper bag or cardboard box, with or without chips from the wet turning.
Soak in DNA (meths?) for a day or two and then bag or wrap in paper.
Wax/seal the end grain and bag.
Etc.
Then wait several weeks to a year, depending upon the piece and method used. Someone in your area will probably have a method that works well for them. Try to rough out to a uniform wall thickness with no sharp corners/edges.

stuffy
16th Dec 2009, 02:52 AM
Hi Oakchip.
When your starting out turning green timber is a good option. It takes a while to build up a supply of good dry turning blanks. It also gives you practise without wasting more valuable stuff.
Many proffessional bowl turners will rough out blanks and put them aside for 6 months or more to season. To do this the bowl is best turned to an even thickness
throughout so it dries evenly. A large spigot or base will affect the seasoning, so give consideration to how you'll remount it. I normally leave centre marks top and bottom on smaller stuff so I can remount between centres to re-turn the spigot.
It can take some trial and error to get the thickness right. Too thick & it'll crack, too thin and you wont be able to turn it round again. The amount it moves is surprising.
Once roughed out the blank can be sealed with end grain sealer or thinned down PVA, or buried in shavings and put in a dark corner, or for smaller items stuck in plastic bag to control humidity.
The other option is to turn to a thin wall thickness and finish by hand when dry. This will require more care in the seasoning process and probably result in more failures, but it can have a nice effect on burls resultig in a nice wavy surface.
You'll need to rough out in a relatively short time so no stopping for lunch halfway!, by the time you come back it 'll be oval!
Well thats a start anyway...Oh and don't bother with spindle turning green wood for now.
Best Wishes and Happy Turning, :):):)
Steve

brendan stemp
16th Dec 2009, 07:55 AM
Well I love turning timber green and letting it warp. It makes for very easy, dust free woodturning and some timbers can warp quite symmetrically, e.g. sheoak. To sand green timber use wet n' dry sandpaper and water. Microwave it to accelerate the drying process.

NeilS
16th Dec 2009, 09:21 AM
....or buried in shavings and put in a dark corner



This is my preferred method. Probably more important to put in a low draft than a dark spot. The dark corner is OK for some wood at some times of the year, but with some woods in wet/humid weather they are more likely to go mouldy (the blue, not the nice spalting type).

There is a percentage loss with this method, as there is to varying degrees with most other methods, but I find that that there is less fussing around with this method which more than compensates for the loses.

.....

rsser
16th Dec 2009, 12:09 PM
If you green turn in one go, it should be done in one session. Wrap in a plastic bag even if you go off for a cuppa.

As Brendan says, it can go oval and look quite effective - if you aim for this make sure your blank in centred in relation to the heart of the log.

When green roughing I leave a tenon inside for remounting on a chuck.

When gripping with a chuck a couple of layers of kitchen wrap will stop staining. And make sure you clean up all bare metal when you're finished to avoid corrosion.

When drying -however it's done - check it often. I allow 3 months usually when a bunch are stacked together. You can weigh a bowl periodically and when it stops dropping you're ready to roll.

While drying particularly watch for shrinking around knots - if it's good wood I'll run a bead of CA around each one after turning it.

oakchip
17th Dec 2009, 10:08 PM
G'day all
thanks for the replies and info. Some good tips there. I can see that by roughing out the green blank you can see what the grain in the project will look like, and greatly speed up the seasoning process. Sounds like a good way to go to me.

Cheers
oakchip

Ed Reiss
18th Dec 2009, 12:33 PM
Welcome to the asylum oakchip :U

Nothing more to add to the advise given by the others, however check out if there is a turners club in your area...usually a good mix of experienced and not so experienced but a wealth of information.

Look forward to a pic or two of your turnings.