% moisture content

[Wildman]

I started woodturning last month i first turned some sycamore that had been cut from the hedgerow the previous year but left in the open. So no surprise that once turned it dried rapidly and split. The rest of the wood is now being stacked under cover. I have thought of getting a percentage moisture meter so that I can monitor it. What would be a reasonable figure to dry to in order to prevent spliting. Will air dried without covering ever be suitable, assuming no rain for a few days, hee hee. how long would you think to season the wood.

 

[boysie39]

Hey Wildman , cant say I know too much about the drying process meself but in the Sticky section on here it is discussed by some people who know .So if you go there you may get some ideas .

 

[Paul.J]

Usually drying time for timber is to allow twelve months for every inch of thinkcness,so 1" thick timber will need 1 year of drying.
But i wouldn't bother you are better off part turning a piece and either wrapping it in paper or putting it in a plastic bag,turning it inside out daily to get rid of the moisture and stop the mould growing,until all the moisure is out the wood,then you can finish turn your piece.This method is more suited to bowls hollow forms etc.
You can even finish the piece straight off and keep it in a cardboard box in a cool place,away from any draughts etc, until it is dry enough.This method can give some distortion to the wood which makes it look interesting.

 

[CHJ]

...... What would be a reasonable figure to dry to in order to prevent spliting. .........

Need to be below 10-12% if turning to finish size, if above that then turning 'green' oversize and drying as suggested by Paul before remounting and finish turning is an option.

Very important that you keep the rough turned item an even thickness and be prepared for a green bowl blank 200mm diameter to shrink 20mm across the grain.

A typical Green Turned Bowl dependant on your drying location it may take considerably longer to finish shrinking than the item featured.

 

[János]

Hello,

Wood left to dry in free air will dry slowly. Removing the bark would be a wise thing: the wood dries faster, and it reduces the danger of insect or fungal attack. The moisture content of "air dry" wood stored in free air on average European climate is 12~18 percent moisture, depending on the season and location. In a centrally heated or air conditioned space the wood dries to 6~8 percent moisture. This amount of moisture change causes large and unpredictable amounts of dimensional changes (shrinking, swelling, distortion, warping). Rough turning is a wise option. You should avoid abrupt changes of wall thickness, as those are potential sources for cracks.
In a hurry, you can cover the endgrain surfaces of the blank with brown paper, glued on with PVAc, and slowly dry it in an electric or gas household/kitchen oven, set to 50~70 degrees centigrade. The wood will shrink a lot, and dry to near zero moisture in a day. With a little luck, it could dry without developing cracks. After drying, leave it alone for a few days, so it could take up a little moisture.

I tried this method, and it works well enough, but it is unsuitable for drying freshly felled wood.

But try it for yourself! :wink:

Have a nice day,

János

 

[Tazmaniandevil]

I dry freshly cut stock in the airing cupboard, up on a high shelf out of everyone's way. Seal the end grain and remove the bark (or rough turn it to near round) then put it away wrapped in newspaper.
Weigh it every so often until the weight stops changing, then you're good to go.

HTH